Download Burnham – Gas Boiler Controls Wiring & Application Guide

Gas Boiler Controls
Wiring & Application Guide
Featuring Burnham® Brand IQ Boiler Control
and Intelligent Hydronic Control Systems
boiler
control
ES2™
Intelligent
Hydronic Control
ESC™
Series 3™
Series 2™
©2013 U.S. Boiler Company
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
1
08/23/13
Table of Contents
1.0Introduction............................................................................................................................ 3
2.0
IQ Gas Boiler Control System........................................................................................................................................... 4
2.1 Single Zone Heating................................................................................................................................................ 5
2.2 Single Zone Heating, Power Stealing Thermostat.................................................................................................... 6
2.3 Single Zone Heating, IWH w/TPI Control................................................................................................................. 7
2.4 Single Zone Heating, IWH w/Aquastat Control........................................................................................................ 8
2.5 Two Zone Heating ................................................................................................................................................... 9
2.6 Zone Valves Heating.............................................................................................................................................. 10
2.7 Zone Valves Heating, IWH w/TPI Control, 2 Circulators........................................................................................ 11
2.8 Zone Valves Heating, IWH w/Aquastat Control, 2 Circulators................................................................................ 12
2.9 Zone Valves Heating, IWH w/TPI Control, 1 Circulators, No Priority..................................................................... 13
2.10 Zone Valves Heating, IWH w/Aquastat Control, 1 Circulators, No Priority............................................................. 14
2.11 Zone Valve Control Heating, IWH w/TPI Control, 2 Circulator............................................................................... 15
2.12 Zone Valve Control Heating, IWH w/Aquastat Control, 2 Circulator....................................................................... 16
2.13 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulator............................................................................... 17
2.14 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator....................................................................... 18
2.15 Zone Switching Relay Heating............................................................................................................................... 19
2.16 Zone Switching Relay Heating, IWH w/TPI Control............................................................................................... 20
2.17 Zone Switching Relay Heating, IWH w/Aquastat Control....................................................................................... 21
3.0
IQ Gas Boiler Control System, Outdoor Reset Card..................................................................................................22-24
3.1 Single Zone Heating.............................................................................................................................................. 25
3.2 Single Zone Heating, IWH w/TPI Control............................................................................................................... 26
3.3 Single Zone Heating, IWH w/Aquastat Control...................................................................................................... 27
3.4 Zone Valves Heating, IWH w/TPI Control, 2 Circulators........................................................................................ 28
3.5 Zone Valves Heating, IWH w/Aquastat Control, 2 Circulators................................................................................ 29
3.6 Zone Valves Heating, IWH w/TPI Control, 1 Circulators, No Priority..................................................................... 30
3.7 Zone Valves Heating, IWH w/Aquastat Control, 1 Circulators, No Priority............................................................. 31
3.8 Zone Valve Control Heating, IWH w/TPI Control, 2 Circulator............................................................................... 32
3.9 Zone Valve Control Heating, IWH w/Aquastat Control, 2 Circulator....................................................................... 33
3.10 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulator............................................................................... 34
3.11 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator ...................................................................... 35
3.12 Zone Switching Relay Heating, IWH w/TPI Control............................................................................................... 36
3.13 Zone Switching Relay Heating, IWH w/Aquastat Control....................................................................................... 37
4.0
Intelligent Hydronic Control (IHC) Series 2 & PVG Boilers Only
4.1 Single Zone Heating.............................................................................................................................................. 38
4.2 Single Zone Heating, Power Stealing Thermostat.................................................................................................. 38
4.3 Single Zone Heating, Indirect Water Heater (IWH) w/TPI Control.......................................................................... 39
4.4 Single Zone Heating, IWH w/Aquastat Control...................................................................................................... 40
4.5 Two Zones Heating................................................................................................................................................ 41
4.6 Zone Valves Heating.............................................................................................................................................. 42
4.7 Zone Valves Heating, IWH w/TPI Control, 2 Circulators........................................................................................ 43
4.8 Zone Valves Heating, IWH w/Aquastat Control, 2 Circulators................................................................................ 44
4.9 Zone Valves Heating, IWH w/TPI Control, 1 Circulators, No Priority..................................................................... 45
4.10 Zone Valves Heating, IWH w/Aquastat Control, 1 Circulators, No Priority............................................................. 46
4.11 Zone Valve Control Heating, IWH w/TPI Control, 2 Circulator............................................................................... 47
4.12 Zone Valve Control Heating, IWH w/Aquastat Control, 2 Circulator....................................................................... 48
4.13 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulator............................................................................... 49
4.14 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator....................................................................... 50
4.15 Zone Switching Relay Heating............................................................................................................................... 51
4.16 Zone Switching Relay Heating, IWH w/TPI Control............................................................................................... 52
4.17 Zone Switching Relay Heating, IWH w/Aquastat Control....................................................................................... 53
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
2
08/23/13
1.0 Introduction
Intelligent Hydronic Control and IQ Control Systems included on various Burnham Brand boilers contain features and capabilities, which
can improve heating system operation, reduce fuel costs, improve comfort, and efficiency. By including unique capabilities, Burnham
brand boilers can do more, with less field wiring, and fewer aftermarket controls and components – improving the operation of both new
and replacement boiler installations.
These application drawings include detailed wiring diagrams, and set-up details, allowing installers to fully utilize the capability and
versatility of the control systems. These applications can save installers time and money on just about any heating system – whether it’s
a new installation, or replacing an older, less efficient boiler.
Notice:
While this manual contains wiring diagrams and set-up details, the Installation Operating and Service Instruction’s provided with
each Burnham brand boiler must be followed.
Notice:
Install wiring and electrically ground boiler in accordance with requirements of the authority having jurisdiction, or in absence of
such requirements the National Electrical Code, ANSI/NFPA 70, and/or the CSA C22.1 Electric Code.
Using this Guide
Line VoltageAbbreviations
L1 – 120Vac Hot – Black L2 – 120Vac Neutral - White
Ground - Green
IHC Intelligent Hydronic Control
OCP
IQ Option Panel
TPI
Alliance IWH control
IQ
(Gas Boiler System) Combination of IHC and OCP on the boiler
“T-T”
Thermostat connection terminals
Low Voltage
Polarity Important
Red 24 Vac Hot
White (Grey) 24Vac Ground
Polarity Not Important
Blue wires
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
3
08/23/13
2.0 IQ Gas Boiler Control System
The Burnham ES2, ESC & Series 3 boilers feature Burnham’s IQ gas Boiler Control system, which greatly simplifies installation and
set-up in both existing and new heating systems. The IQ Control system contains many unique features and capabilities that save the
installer time and take the mystery out of controls by providing simple, clear information about settings, status, and diagnostics on an
LED display on the boiler. The IQ gas Boiler Control System consists of the following components:
Intelligent Hydronic Gas Boiler Control features an integrated
boiler temperature sensor, and ignition control into one for seamless
operation. The Intelligent Hydronic Control features an LED read-out,
which displays operating information such as boiler status and boiler
water temperature. The Intelligent Hydronic Control also displays
diagnostic info such as run time hours, the number of heating cycles,
flame signal strength, and error codes for improved diagnostics
The IQ Option Panel is a separate control panel that accepts IQ
Option Cards for added efficiency and safety. IQ Option Cards snap
into any one of the three Slots in the Option Panel, and are instantly
recognized when the IQ System is powered up. A separate LED
display provides setting, status, & diagnostic info for each of the
IQ Option Cards, greatly simplifying the set-up and operation of the
control. IQ Option Cards are cost effective, they save time, and they
are functionally superior to stand alone Limits, LWCO’s and Outdoor
Reset controls. Not available with the Series 2 Boiler.
IQ Option Cards are snap-in control modules which attach to the
Option Panel, and contain various control upgrades, such as Auxiliary
High Temperature Limit, Low Water Cut-Off protection, and Outdoor
Air Reset. There’s an IQ Option Card for each feature. Option Cards
simply plug into the Option Panel, and feature a one or two wire
connection to a sensor. Not available with the Series 2 boiler.
Intelligent Hydronic Control Adjustment Mode Options
The Intelligent Hydronic
Control’s (IHC) “Dh”
parameter provides the ability
to control the two separate
heating demands or a heating
demand and an Indirect Water
Heater (IWH) demand without
the use of additional controls.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
Parameter
Range
Parameter Description
Default
HL
dF
Or
PP
St
Pt
dh
F-C
140°F – 220°F
High Limit Setting
180°F
10°F – 30°F
High Limit Differential
15°F
0 – 20 Minutes
Circulator Overrun Time
0 Minutes
2 –20 Minutes
Circulator Pre-purge Time
2 Minutes
140°F –180°F
Start Temperature
140°F
On – Off
Priority Time (DHW)
On
Dh or TT2
DH Terminal Function
dh
F or C
Degrees F or C
F
4
08/23/13
2.0 IQ Gas Boiler Control System
2.1 Single Zone Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
L2
Overcurrent
Protection/
Disconnect
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
12
123
123TT
Thermostat 1
Explanation:
This arrangement can be used when an IQ gas boiler is connected to a single zone heating system.
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system wire.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
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08/23/13
2.0 IQ Gas Boiler Control System
2.2 Single Heat Zone, Power Stealing Thermostat
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
12
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left T is 24V AC positive
123
123TT
Thermostat 1
Explanation:
This arrangement can be used with a single zone heating system with a power stealing thermostat
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
6
08/23/13
2.0 IQ Gas Boiler Control System
2.3 Single Heat Zone Heating, IWH w/TPI Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
120V AC
Power
Supply
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
System
Circulator
DHW/Zone
Circulator
12
Alliance SL
Indirect
Water Heater
TPI Control
123
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
pump/TT
24V
123TT
Thermostat 1
Explanation:
This arrangement can be used with a single heat zone and DHW demand from the TPI control.
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
The TPI control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone circulator
wire.
• The IHC parmater “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without at time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
controls.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
7
08/23/13
2.0 IQ Gas Boiler Control System
2.4 Single Heat Zone Heating, IWH w/Aquastat Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW
Circulator
System
Circulator
DHW/Zone
Circulator
12
123
IWH Aquastat
Controls
123TT
Thermostat 1
Explanation:
This arrangement can be used with a single heat zone and DHW demand from an Aquastat.
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
The TPI control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone circulator
wire.
• The IHC parmater “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without at time out period.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
8
08/23/13
2.0 IQ Gas Boiler Control System
2.5 Two Zone Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
Zone 1
Circulator
Red
Zone 2
Circulator
System
Circulator
DHW/Zone
Circulator
12
123
Thermostat 2
123TT
Thermostat 1
Explanation:
This arrangement allows the boiler to respond to two heating demands through the IHC control and operate both circulators
without priority.
• A Zone-1 thermostat wired to the OCP “TT” Terminals provides a Zone-1 heating demand and energizes the yellow system
circulator wire. A Zone-2 thermostat wired to the IHC “1” and “2” terminals provides a Zone-2 demand and energizes the red
DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “tt2” and the “Pt” Priority Time parameter is ignored so both circulators can run
simultaneously.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
9
08/23/13
2.0 IQ Gas Boiler Control System
2.6 Zone Valve Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
40VA
Transformer
Field Installed
L1
Thermostat 1
120V AC
Power
Supply
Thermostat 2
System
Circulator
DHW/Zone
Circulator
12
123
Thermostat 3
24V AC Positive
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
L2
Power
Supply
120/60/1
123TT
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves.
• The zone valve end switches wired to the OCP “TT” Terminals, provide a heating demand, and energize the yellow system
circulator wire.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
10
08/23/13
2.0 IQ Gas Boiler Control System
2.7 Zone Valve Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
L1
Thermostat 1
Thermostat 2
System
Circulator
DHW/Zone
Circulator
12
pump/TT
40VA
Transformer
Field Installed
120V AC
Power
Supply
24V
Alliance SL
Indirect
Water Heater
TPI Control
123
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Thermostat 3
24V AC Positive
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
L2
Power
Supply
120/60/1
123TT
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from a TPI control.
• The zone valve end switches wired to the OCP “TT” Terminals, provide a heating demand, and energize the yellow system
circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provide a DHW demand and energize the red DHW/
Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on” it will prioritize the
IWH without a time out period
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
11
08/23/13
2.0 IQ Gas Boiler Control System
2.8 Zone Valve Heating, IWH w/Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW
Circulator
System
Circulator
DHW/Zone
Circulator
12
123
IWH Aquastat
Control
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat 2
Thermostat 3
24V AC Positive
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
L2
Power
Supply
120/60/1
123TT
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from an Aquastat control.
• The zone valve end switches wired to the OCP “TT” Terminals, provide a heating demand, and energize the yellow system
circulator wire. The IWH Aquastat Control wired to the IHC “1” & “2” terminals provide a DHW demand and energize the red
DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on” it will prioritize the
IWH without a time out period
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
12
08/23/13
2.0 IQ Gas Boiler Control System
2.9 Zone Valve Heating, IWH w/TPI Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
System
Circulator
120V AC
Power
Supply
Yellow
System
Circulator
Red
With this application, there will
not be DHW priority
System
Circulator
DHW/Zone
Circulator
12
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the domestic
water side of the indirect water heater
Alliance SL
Indirect
Water Heater
TPI Control
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
pump/TT
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat 2
123
24V
24V AC Positive
L2
Power
Supply
120/60/1
123TT
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This arrangement allows the use of zone valves for heat and hot water using a single circulator without DHW priority.
• The heating zone valve end switches wired to the OCP “TT” Terminals, provide a heating demand, and energize the yellow
system circulator wire. The TPI Control connected zone valve end switch wired to the IHC “1” & “2” terminals provide a
DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no priority in this application due to using only one circulator
• Wiring the DHW zone valve end switch to the IHC will avoid the boiler temperature delayed start used on heat demand
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
13
08/23/13
2.0 IQ Gas Boiler Control System
2.10 Zone Valve Heating, IWH w/TPI Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
With this application, there will
not be DHW priority
12
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the domestic
water side of the indirect water heater
40VA
Transformer
Field Installed
L1
Thermostat 1
123
IWH Aquastat
Control
Thermostat 2
24V AC Positive
L2
Power
Supply
120/60/1
123TT
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This arrangement allows the use of zone valves for heat and hot water using a single circulator without DHW priority.
• The heating zone valve end switches wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow
system circulator wire. The IWH Aquastat Control connected zone valve end switch wired to the IHC “1” & “2” terminals
provide a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no priority in this application due to using only one circulator.
• Wiring the DHW zone valve end switch to the IHC will avoid the boiler temperature delayed start used on heat demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and IHC.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
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2.0 IQ Gas Boiler Control System
2.11 Zone Valve Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
Alliance SL
Indirect
Water Heater
TPI Control
PUMP END
SWITCH
X
X
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
ZONE 3
PRIORITY
ON
OFF
DHW/Zone
Circulator
123
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
pump/TT
24V
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
System
Circulator
12
Thermostat 1 Thermostat 2 Thermostat 3
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
123TT
PRIORITY
ZONE 3
1 2 3 4
Explanation:
This application uses a zone valve control for heating demands and the DHW demand using at TPI control
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the red DHW/
Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”, and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
Control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
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08/23/13
2.0 IQ Gas Boiler Control System
2.12 Zone Valve Control Heating, IWH w/Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
PUMP END
SWITCH
X
X
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
DHW/Zone
Circulator
123
IWH Aquastat
Control
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
System
Circulator
12
Thermostat 1 Thermostat 2 Thermostat 3
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
123TT
PRIORITY
ZONE 3
1 2 3 4
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This application uses a zone valve control for heating demands and the DHW demand using an Aquastat control
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The IWH Aquastat Control wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the
red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”, and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
16
08/23/13
2.0 IQ Gas Boiler Control System
2.13 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulator
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
12
POWER IN
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
24V
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
PUMP END
SWITCH
X
X
123
Alliance SL
Indirect
Water Heater
TPI Control
pump/TT
X X
ISOLATED
END SWITCH
System
Circulator
DHW/Zone
Circulator
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
123TT
PRIORITY
ZONE 3
1 2 3 4
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
one circulator. Priority is controlled by the zone valve relay control.
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The Zone 3 Pump end switch wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the
red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no circulator priority in this application due to using only one
circulator.
• Wiring the zone valve control “zone pump 3 end switch” to DHW terminals will avoid the boiler temperature delayed start
used on heat demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the TPI Control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
17
08/23/13
2.0 IQ Gas Boiler Control System
2.14 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
Yellow
12
R W C
ZONE 3
PRIORITY
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
ZONE 3 PUMP
END SWITCH
N/O COM N/C
123
IWH Aquastat
Control
ZVC 403-4
PUMP END
SWITCH
X
X
System
Circulator
DHW/Zone
Circulator
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
123TT
PRIORITY
ZONE 3
1 2 3 4
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
one circulator. Priority is controlled by the zone valve relay control.
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The Zone 3 Pump end switch wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the
red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no circulator priority in this application due to using only one
circulator.
• Wiring the zone valve control “zone pump 3 end switch” to DHW terminals will avoid the boiler temperature delayed start
used on heat demand.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
18
08/23/13
2.0 IQ Gas Boiler Control System
2.15 Zone Switching Relay Heating
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
GND
Boiler Junction Box
Line Voltage Wiring Connections
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
12
24V AC
X X
R W
R W R W
ISOLATED ZONE 1 ZONE 2 ZONE 3
PRIORITY
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
FUSE
5
AMP
120 VAC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120 VAC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
123
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
ZONE 1
ZONE 2
ZONE 3
INPUT
120V AC
N
H
SR 503-4
123TT
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a zone switching relay.
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
19
08/23/13
2.0 IQ Gas Boiler Control System
2.16 Zone Switching Relay Heating, IWH w/TPI Control
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
GND
L2
Boiler Junction Box
Line Voltage Wiring Connections
Green
White
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
DHW
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
12
24V AC
X X
R W
R W R W
ISOLATED ZONE 1 ZONE 2 ZONE 3
PRIORITY
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove jumper
between ZC & ZR
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120 VAC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
Alliance SL
Indirect
Water Heater
TPI Control
ZONE 3
PRIORITY
ON
OFF
pump/TT
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
24V
LED
INDICATORS
POWER
ZONE 1
ZONE 2
ZONE 3
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
INPUT
120V AC
N
123
H
SR 503-4
123TT
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a Zone Switching Relay.
IHW takes priority through the IHC control via the yellow system pump wire.
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the red DHW/
Zone circulator wire.
• A heat demand will energize the yellow wire which will supply voltage to the zone pumps via the “ZC” terminals on the zone
relay. When the DHW demand activates, the IHC will de-energize the yellow system circulator wire and energize the red DHW
circulator. When the DHW demand expires, the IHC will de-energzie the red wire and re-energize the yellow wire, providing
there is still a call for heat
• The IHC parameter “dh” must be set to “dh”, and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
Control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
20
08/23/13
2.0 IQ Gas Boiler Control System
2.17 Zone Switching Relay Heating, IWH w/Aquastat Control
GND
L2
Boiler Junction Box
Line Voltage Wiring Connections
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
Green
White
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
DHW
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
1 2
24V AC
X
X
R
W
R
W
R W
ZONE 3
ZONE 2
PRIORITY
ISOLATED ZONE 1
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove jumper
between ZC & ZR
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
ZONE 3
PRIORITY
ON
OFF
IWH Aquastat
Control
LED
INDICATORS
POWER
ZONE 1
ZONE 2
ZONE 3
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Left “T” is 24V AC positive
INPUT
120 VAC
N
1 2 3
H
SR 503-4
123TT
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a Zone Switching Relay.
• The zone control end switch wired to the OCP “TT” Terminals, provide a heating demand, and energizes the yellow system
circulator wire. The IWH Aquastat Control wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the
red DHW/Zone circulator wire.
• A heat demand will energize the yellow wire which will supply voltage to the zone pumps via the “ZC” terminals on the zone
relay. When the DHW demand activates, the IHC will de-energize the yellow system circulator wire and energize the red DHW
circulator. When the DHW demand expires, the IHC will de-energzie the red wire and re-energize the yellow wire, providing
there is still a call for heat
• The IHC parameter “dh” must be set to “dh”, and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
21
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
The IQ Outdoor Reset Option Card is an auxiliary control
designed specifically for all Burnham products that
feature the IQ Control System.
The device than plugs into the IQ Option Panel making it
the quickest, simplest way to install the energy savings
and improved comfort of a full-featured outdoor reset
system in any nearly heating system.
The included weatherproof outdoor temperature sensor
is mounted outside the building, and a 2-wire connection
is all that’s required to connect the Option Card. An
additional 2-wire connection to the DHW Aquastat
provides a DHW demand.
IQ
option
card
The IQ Outdoor Reset Option Card contains an impressive
list of features normally found only on expensive, standalone control systems. A simple click is all it takes to add
the these great features:
• Adjustable reset ratio
• Selectable & Adjustable Temperature Boost
• Domestic Hot Water Set Point
• Selectable, Adjustable Domestic Priority
• Selectable, Adjustable Domestic Priority Protection
• Built-In Diagnostics display error codes on LED
display
• Can be easily by-passed for service or diagnostics
• Settings and status is displayed on IQ Option Panel
• Adjustments made right on the boiler
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
22
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
IQ Outdoor Reset Option Card Settings / Defaults
Display
Description
Range
Factory Defaults
View Mode
SP
ot
Set Point
Set Point of Boiler
180°F
Outdoor Temperature
Actual Temp from Sensor
Adjustment Mode
dS
Pt
tb
Lo
Ho
Lb
Hb
Lt
F-C
Domestic Set Point
Range: 150°F – 180°F
180°F
Priority Time
Range: 0-101 Minutes
0 Minutes
Boost Time
Range: 0-30 Minutes
20 Minutes
Low Outdoor Temp
Range: 50°F – 32°F
0°F
High Outdoor Temp
Range: 35°F – 100°F
70°F
Low Boiler Temp
Range: 70°F – 180°F
110°F
High Boiler Temp
Range: 70°F – 220°F
180°F
Minimum Boiler Temp
Range: 70°F – 180°F
130°F
Display in °F or °C
Degrees: °F/°C
Degrees °F
Error Codes
Err 18
Err 53
Err 89
Electronics Failure
Replace Card
Temp Sensor Failure
Replace Sensor
Communication Error
Loose wire between boiler control and option panel or card failure
The IQ Option Panel features a 3-digit LED, which
displays status, settings, and error codes
for any IQ Option Cards Installed on the boiler.
• The “I” button is used to toggle between each
option card.
• The “UP” and “Down” arrows are used to adjust settings when the IQ Option Panel is in
the Adjust Mode.
• When all 3 buttons are held down for 3
seconds, the Option Panel will enter the Adjust
Mode and an underscore will be displayed.
• If no keys are pressed, after 5 minutes the
Option Panel will automatically return to the
View Mode.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
23
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
Optional Control Panel – ODR Card Adjustable Mode
The optional Control Panel (OCP) has three usable slots for plug
in cards. Cards can be plugged in in any order. If less than three
cards are used they can be in any slot, they do not have to be in any
specific order. Once the card is placed in a slot it cannot be moved
to another slot without using the “Lrn” function on the OCP. If the
card is moved you will receive an error code but no damage will
occur to the card.
The control has three buttons used to view
error codes and access the cards to view or
change the parameters. If using the Outdoor
Reset (ODR) card you may want to change
some of the outdoor reset parameters for a
more efficient operation.
If there is an IWH on the jobsite it will need
to be wired to the ODR card to override the
ODR feature on a call for DHW. The card will
prioritize the DHW demand and you may be
required or choose to change the Priority
Time (Pt) the IWH will run before the heating
circulators will be re-energized. A required
priority time change would be if you have two
circulators, one for heating and the other for
DHW. The “Pt” factory default is “0” minutes,
left at “0” will start both pumps wired to the
boiler on a DHW demand. Starting just the
DHW circulator on a DHW demand you would change the “Pt”
setting from “0” to any value more than “0”. A normal range would
be 20 minutes or more depending on tank size and demand.
The ODR card is located in the #2 slot on the OCP pictured above.
To access the card follow the directions below;
1. Press and release the “I” button until “C2” appears on the display.
2. Press one of the Arrow buttons
3. Press and hold all three buttons at the same time until an
underscore appears on the display where the bottom of the third
digit would appear.
4. Press the “I” button until you see the Priority Time (Pt) parameter.
5. Press the “up arrow” button to set to desired number of minutes.
6. Press the “I” button to advance to the next parameter, this also
saves the setting
7. Continue to press the “I” button until “bAc” is displayed
8. Press an arrow key to leave the parameter adjust mode.
You can stop at any parameter and make changes if needed.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
24
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.1 Single Zone Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Gnd
Left “T” is 24V AC Positive
123TT
1234
Thermostat 1
Explanation:
This arrangement can be used when an IQ Gas Boiler is connected to a singe zone heating system
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
25
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.2 Single Zone Heating, IWH w/TPI Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
Zone 1
Circulator
Zone 2
Circulator
Alliance SL
Indirect
Water Heater
TPI Control
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Gnd
Left “T” is 24V AC Positive
pump/TT
123TT
1234
24V
Thermostat 1
Explanation:
This arrangement can be used when there is a single heat zone and a DHW demand.
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
The TPI Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW demand and energizes the
red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”
• Priority time (Pt) and DHW Setpoint can be set on the IQ Outdoor Reset Option Card.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
Control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
26
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.3 Single Zone Heating, IWH w/Aquastat Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
Zone 1
Circulator
Zone 2
Circulator
IWH Aquastat
Control
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
123TT
1234
Thermostat 1
Explanation:
This arrangement can be used when there is a single heat zone and a DHW demand.
• A thermostat wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
The IWH Aquastat Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW demand and
energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
27
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.4 Zone Valves Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
DHW
Circulator
Alliance SL
Indirect
Water Heater
TPI Control
pump/TT
Thermostat 1
40VA
Transformer
Field Installed
L1
Thermostat 2
24V
Thermostat 3
24V AC Positive
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
L2
Power
Supply
120/60/1
123TT
1234
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from a TPI control.
• The zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system
circulator wire. The TPI Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW demand and
energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
Control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
28
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.5 Zone Valves Heating, IWH w/Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
DHW
Circulator
IWH Aquastat
Control
Thermostat 1
40VA
Transformer
Field Installed
L1
Thermostat 2
Thermostat 3
24V AC Positive
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
L2
Power
Supply
120/60/1
123TT
1234
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from an Aquastat control.
• The zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system
circulator wire. The IWH Aquastat Control connected zone valve end switch wired to the IQ Outdoor Reset Option Card “3” &
“4” terminals provides a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
29
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.6 Zone Valves Heating, IWH w/TPI Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
L1
System
Circulator
Red
DHW/Zone
Circulator
Alliance SL
Indirect
Water Heater
TPI Control
With this application, there will NOT be DHW priority
pump/TT
Thermostat 1
40VA
Transformer
Field Installed
Yellow
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the domestic
water side of the indirect water heater
120V AC
Power
Supply
Terminal 4 is 24V AC Positive
24V
Thermostat 2
24V AC Positive
L2
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
Power
Supply
120/60/1
123TT
1234
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from a TPI control.
• The zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system
circulator wire. The TPI Control connected zone valve end switch wired to the IQ Outdoor Reset Option Card “3” & “4”
terminals provides a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no priority in this application due to using only one circulator.
• Wiring the zone valve end switches to DHW terminals will avoid the boiler temperature delayed start used on heat demand
and provides a DHW setpoint.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and the TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
30
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.7 Zone Valves Heating, IWH w/Aquastat Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Thermostat 1
40VA
Transformer
Field Installed
L1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the domestic
water side of the indirect water heater
120V AC
Power
Supply
IWH Aquastat
Control
With this application, there will NOT be DHW priority
Terminal 4 is 24V AC Positive
Thermostat 2
24V AC Positive
L2
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
Power
Supply
120/60/1
123TT
1234
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from an Aquastat control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The IWH Aquastat Control connected zone valve end switch wired to the IQ Outdoor Reset Option
Card “3” & “4” terminals provides a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no priority in this application due to using only one circulator.
• Wiring the zone valve end switches to DHW terminals will avoid the boiler temperature delayed start used on heat demand
and provides a DHW setpoint.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
31
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.8 Zone Valve Control Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
POWER IN
FUSE
5 AMP
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
Alliance SL
Indirect
Water Heater
TPI Control
ZONE 3
PRIORITY
ZONE 3
ON
PRIORITY
OFF
pump/TT
123
24V
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
ZONE 3 PUMP
END SWITCH
N/O COM N/C
DHW/Zone
Circulator
R W C
R W C
ZVC 403-4
PUMP END
SWITCH
X
X
System
Circulator
12
Thermostat 1 Thermostat 2 Thermostat 3
X X
ISOLATED
END SWITCH
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone valve control and a DHW demand
from a TPI control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The TPI Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW
demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”.
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
32
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.9 Zone Valve Control Heating, IWH Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
System
Circulator
DHW/Zone
Circulator
12
Thermostat 1 Thermostat 2 Thermostat 3
123
IWH Aquastat
Control
POWER IN
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
X X
ISOLATED
END SWITCH
FUSE
5 AMP
R W C
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
ZONE 3
PRIORITY
ZVC 403-4
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
PUMP END
SWITCH
X
X
ZONE 3
PRIORITY
ON
OFF
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone valve control and a DHW demand
from an Aquastat control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The IWH Aquastat Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a
DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”.
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
33
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.10 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
System
Circulator
Yellow
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
12
POWER IN
pump/TT
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
ZONE 3
PRIORITY
ZONE 3
ON
PRIORITY
OFF
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V
123
Alliance SL
Indirect
Water Heater
TPI Control
R W C
ZVC 403-4
PUMP END
SWITCH
X
X
System
Circulator
DHW/Zone
Circulator
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone valve control and a DHW demand
from a TPI control.
• The zone control end switch wired to the OCP “TT” terminals provide a heating demand and energizes the yellow system
circulator wire. The zone 3 pump end switch wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW
demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. Priority time and DHW setpoint can be set on the IQ Outdoor Reset Option
Card.
• Wiring the zone valve control “zone pump end switch” to DHW terminals will avoid the boiler temperature delayed start used
on heat demand and provides a DHW setpoint.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and the TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
34
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.11 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
System
Circulator
Yellow
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
12
R W C
ZONE 3
PRIORITY
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
ZONE 3
PRIORITY
ON
OFF
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
ZONE 3 PUMP
END SWITCH
N/O COM N/C
123
IWH Aquastat
Control
ZVC 403-4
PUMP END
SWITCH
X
X
System
Circulator
DHW/Zone
Circulator
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone valve control and a DHW demand
from an Aquastat control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The zone 3 pump end switch wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides
a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. Priority time and DHW setpoint can be st on the IQ Outdoor Reset Option
Card.
• Wiring the zone valve control “zone pump end switch” to DHW terminals will avoid the boiler temperature delayed start used
on heat demand and provides a DHW setpoint.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
35
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.12 Zone Switching Relay Heating, IWH w/TPI Control
GND
L2
Boiler Junction Box
Line Voltage Wiring Connections
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
Green
White
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
DHW
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
12
24V AC
X X
R W
R W R W
ISOLATED ZONE 1 ZONE 2 ZONE 3
PRIORITY
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove jumper
between ZC & ZR
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
123
Alliance SL
Indirect
Water Heater
TPI Control
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
pump/TT
24V
POWER
ZONE 1
ZONE 2
ZONE 3
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
INPUT
120V AC
N
H
SR 503-4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone switching relay and a DHW demand
from a TPI control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The TPI Control wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides a DHW
demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”.
• Priority time (Pt) on the ODR card must be set > “0”. See instructions on page 24.
• The IQ Outdoor Reset Option Card will raise or lower the heating system water temperature setpoint based on measured
outside air temperature and will be overridden on a DHW demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
36
08/23/13
3.0 IQ Gas Boiler Control System, IQ Reset Option Card
3.13 Zone Switching Relay Heating, IWH w/Aquastat Control
Overcurrent
Protection/
Disconnect
GND
L2
Boiler Junction Box
Line Voltage Wiring Connections
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
120V AC
Power
Supply
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
DHW
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
12
24V AC
X
X
R
W
R
W
R W
ZONE 3
ZONE 2
PRIORITY
ISOLATED ZONE 1
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove jumper
between ZC & ZR
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
ZONE 3
PRIORITY
ON
OFF
123
IWH Aquastat
Control
LED
INDICATORS
POWER
ZONE 1
ZONE 2
Terminal 2 is 24V AC Positive
Terminal 3 is 24V Ground
Left “T” is 24V AC Positive
ZONE 3
INPUT
120V AC
N
H
SR 503-4
123TT
1234
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing a zone valve control and a DHW demand
from an Aquastat control.
• The heating zone valve end switches wired to the OCP “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The zone 3 pump end switch wired to the IQ Outdoor Reset Option Card “3” & “4” terminals provides
a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”.
• The Priority time (Pt) on the ODR card must be set to > “0”. See instruction on page 24.
• When the zone valve control “zone pump end switch” to DHW terminals will avoid the boiler temperature-delayed start used
on heat demand and provides a DHW setpoint.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the OCP.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
37
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.1 Single Zone Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
1 2
1 2 3
Thermostat 1
Explanation:
This arrangement can be used when an IQ gas boiler is connected to a single zone heating system
• A thermostat wired to the IHC “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
4.2 Single Zone Heating, Power Stealing Thermostat
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
DHW/Zone
Circulator
System
Circulator
1 2
1 2 3
Thermostat 1
Explanation:
This arrangement can be used when an IQ gas boiler is connected to a single zone heating system with a power stealing
thermostat
• A thermostat wired to the IHC “TT” terminals provide a heating demand and energizes the yellow system circulator wire.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
38
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.3 Single Zone Heating, IWH w/TPI Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
120V AC
Power
Supply
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
Alliance SL
Indirect
Water Heater
TPI Control
DHW
Circulator
pump/TT
1 2
1 2 3
24V
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
Thermostat 1
Explanation:
This arrangement can be used when there is a single heat zone and a DHW demand from a TPI control.
• The heating zone valve end switches wired to the IHC “TT” terminals provide a heating demand and energizes the yellow
system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red
DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
39
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.4 Single Zone Heating, IWH w/TPI Control
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
IWH Aquastat
Controls
120V AC
Power
Supply
Red
DHW
Circulator
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
DHW/Zone
Circulator
1 2
1 2 3
Thermostat 1
Explanation:
This arrangement can be used when there is a single heat zone and a DHW demand from an Aquastat control.
• A thermostat wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The
IWH Aquastat Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone
circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
40
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.5 Two Zone Heating
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
L2
Green
White
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
Zone 1
Circulator
Red
Zone 2
Circulator
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
DHW/Zone
Circulator
1 2
1 2 3
Thermostat 2
Thermostat 1
Explanation:
This arrangement allows the boiler to respond to two heating demands through the IHC control and operate both circulators
without priority
• A Zone 1 thermostat wired to the IHC “TT” wires provide a Zone 1 heating demand and energizes the yellow system circulator wire. A Zone 2 thermostat wired to the IHC “1” & “2” terminals provides a Zone 2 demand and energizes the res DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “tt2” and when the “Pt” Priority Time parameter is ignored so both circulators can
run simultaneously.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
41
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.6 Zone Valve Heating
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
DHW/Zone
Circulator
1 2
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat 2
1 2 3
Thermostat 3
24V AC Positive
L2
Power
Supply
120/60/1
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves
• The zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
42
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.7 Zone Valve Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Yellow
System
Circulator
Red
DHW
Circulator
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Thermostat 2
System
Circulator
DHW/Zone
Circulator
1 2
Thermostat 3
1 2 3
Alliance SL
Indirect
Water Heater
TPI Control
24V AC Positive
pump/TT
24V
L2
Power
Supply
120/60/1
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from a TPI control.
• The zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a Zone 2 demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
43
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.8 Zone Valve Heating, IWH w/Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Yellow
System
Circulator
Red
DHW
Circulator
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat WIres
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Thermostat 2
System
Circulator
DHW/Zone
Circulator
1 2
1 2 3
Thermostat 3
IWH Aquastat
Control
24V AC Positive
L2
Power
Supply
120/60/1
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from an Aquastat control.
• The zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a Zone 2 demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
44
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.9 Zone Valve Heating, IWH w/TPI Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
120V AC
Power
Supply
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
System
Circulator
Yellow
System
Circulator
Red
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the domestic
water side of the indirect water heater
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
DHW/Zone
Circulator
1 2
Thermostat 2
24V AC Positive
Alliance SL
Indirect
Water Heater
TPI Control
Terminal 2 is
24V AC Positive
Terminal 1 is
24V AC Ground
pump/TT
24V
1 2 3
Terminal 2 is 24V AC Positive
Terminal 3 is 24V AC Ground
L2
Power
Supply
120/60/1
With this application, there will not be
DHW priority
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from a TPI control.
• The zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control connected zone valve end switch wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt”. There is no priority in this application due to using only one
circulator.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
45
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.10 Zone Valve Heating, IWH w/Aquastat Control, 1 Circulator, No Priority
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
120V AC
Power
Supply
Yellow
System
Circulator
Red
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
DHW/Zone
Circulator
1 2
40VA
Transformer
Field Installed
L1
Thermostat 1
Thermostat 2
1 2 3
IWH Aquastat
Control
24V AC Positive
L2
Power
Supply
120/60/1
With this application, there will not be
DHW priority
NOTE
Zone Valve Terminal 2 must be
connected to 24V AC
Common failure to do so will result in
damaged equipment
Explanation:
This arrangement allows the boiler to respond to a space heating demand utilizing Taco 3-wire zone valves and a DHW demand
from an Aquastat control.
• The heating zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The IWH Aquastat Control connected zone valve end switch wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt”. There is no priority in this application due to using only one
circulator.
• Wiring the DHW zone valve end switch to the IHC will avoid the boiler temperature delayed start used on heat demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
46
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.11 Zone Valve Control Heating, IWH w/TPI Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
System
Circulator
DHW/Zone
Circulator
12
Alliance SL
Indirect
Water Heater
TPI Control
Thermostat 1 Thermostat 2 Thermostat 3
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
24V
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
PUMP END
SWITCH
X
X
ZONE 3
PRIORITY
ON
OFF
123
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
pump/TT
FUSE
5 AMP
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Black
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
two circulators, and offers priority.
• The zone valve end wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/Zone
circulator wire.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC and TPI
control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
47
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.12 Zone Valve Control Heating, IWH w/Aquastat Control, 2 Circulators
Boiler Junction Box
Line Voltage Wiring Connections
GND
Overcurrent
Protection/
Disconnect
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW
Circulator
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
PUMP END
SWITCH
X
X
ZONE 3 PUMP
END SWITCH
N/O COM N/C
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
System
Circulator
DHW/Zone
Circulator
123
IWH Aquastat
Control
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
12
Thermostat 1 Thermostat 2 Thermostat 3
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
an Aquastat.
•
•
The zone control end switch wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/
Zone circulator wire.
The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the IHC control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
48
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.13 Zone Valve Control Heating, IWH w/TPI Control, 1 Circulator
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
Red
POWER IN
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
ZVC 403-4
ZONE 3 PUMP
END SWITCH
N/O COM N/C
DHW/Zone
Circulator
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
123
24V
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
PUMP END
SWITCH
X
X
System
Circulator
12
pump/TT
X X
ISOLATED
END SWITCH
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Alliance SL
Indirect
Water Heater
TPI Control
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
one circulator. Priority is controlled by the zone valve relay control.
• The zone control end switch wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/
Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no circulator priority in this application due to using only one
circulator.
• Wiring the zone valve control “zone pump 3 end switch” to DHW terminals will avoid the boiler temperature delayed start used on heat demand.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid possible damage to the TPI control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
49
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.14 Zone Valve Control Heating, IWH w/Aquastat Control, 1 Circulator
Boiler Junction Box
Line Voltage Wiring Connections
Overcurrent
Protection/
Disconnect
GND
Green
White
L2
Service Switch
(Optional)
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Caution: When using a zone valve on an
IWH, we strongly suggest the use of a
mixing valve installed on the Domestic
water side of the Indirect Water Heater
Red
POWER IN
X X
ISOLATED
END SWITCH
R W C
R W C
ZONE 1
ZONE 2
THERMOSTATS (24V AC)
R W C
ZONE 3
PRIORITY
24V AC ZONE VALVES
ZONE 1
ZONE 2
1 2 3 4
1 2 3 4
ZONE 3
PRIORITY
ON
OFF
DHW/Zone
Circulator
123
LED
INDICATORS
POWER
T STAT 1
T STAT 2
T STAT 3
THREE ZONE
ZONE VALVE CONTROL
ZONE 3 PUMP
END SWITCH
N/O COM N/C
System
Circulator
IWH Aquastat
Control
ZVC 403-4
PUMP END
SWITCH
X
X
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
12
Thermostat 1 Thermostat 2
FUSE
5 AMP
120V AC
Power
Supply
VALVE 1
VALVE 2
VALVE 3
PRIORITY
ZONE 3
1 2 3 4
Explanation:
This application uses a zone valve control for heating demands and the DHW demand wired directly to the IHC control utilizing
one circulator. Priority is controlled by the zone valve relay control.
• The zone control end switch wired to the IHC “TT” wires provide a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provides a DHW demand and energizes the red DHW/
Zone circulator wire.
• The IHC parameter “dh” must be set to “dh”. There is no circulator priority in this application due to using only one
circulator.
• Wiring the zone valve control “zone pump 3 end switch” to DHW terminals will avoid the boiler temperature delayed start used on heat demand.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
50
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.15 Zone Switching Relay Heating
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
GND
Boiler Junction Box
Line Voltage Wiring Connections
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
Yellow
System
Circulator
Red
DHW/Zone
Circulator
Thermostat 1 Thermostat 2 Thermostat 3
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
12
24V AC
X X
R W
R W R W
ISOLATED ZONE 1 ZONE 2 ZONE 3
PRIORITY
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
123
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
ZONE 1
ZONE 2
ZONE 3
INPUT
120V AC
N
H
SR 503-4
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a zone switching relay.
• The zone switching relay end switch wired to the IHC “TT” wires provides a heating demand and energizes the yellow system circulator wire.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
51
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.16 Zone Switching Relay Heating, IWH w/TPI Control
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
GND
Boiler Junction Box
Line Voltage Wiring Connections
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
Black
L1
Power
Supply
120/60/1
DHW
Circulator
Yellow
Red
Thermostat 1 Thermostat 2 Thermostat 3
System
Circulator
DHW/Zone
Circulator
12
24V AC
X
X
R
W
R
W
R W
ZONE 3
ZONE 2
PRIORITY
ISOLATED ZONE 1
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove
Jumper
Between
ZC & 2R
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
Alliance SL
Indirect
Water Heater
TPI Control
ZONE 3
PRIORITY
ON
OFF
Terminal 2 is 24V AC positive
Terminal 3 is 24V AC ground
pump/TT
LED
INDICATORS
123
24V
POWER
ZONE 1
ZONE 2
ZONE 3
INPUT
120V AC
N
H
SR 503-4
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a zone switching relay.
DHW is controllled by the TPI control.
• The zone switching relay end switch wired to the IHC “TT” wires provides a heating demand and energizes the yellow system circulator wire. The TPI Control wired to the IHC “1” & “2” terminals provide a DHW demand and energizes the red
DHW/Zone circulator wire.
• A heat demand will energize the yellow wire which will supply voltage to the zone pumps via the “ZC” terminals on the zone
relay. When the DHW demand activates, the IHC will de-energize the yellow system circulator wire and energize the red DHW
circulator. When the DHW demand expires, the IHC will de-energize the red wire and re-energize the yellow wire providing
there is still a call for heat.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
• CAUTION: Proper polarity must be maintained on the red and white wires to avoid damge to the IHC and TPI control.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
52
08/23/13
4.0 Intelligent Hydronic Control (IHC)
4.17 Zone Switching Relay Heating, IWH w/Aquastat Control
NOTE
Supply power to Zone Switching Relay
from same discount as boiler
Overcurrent
Protection/
Disconnect
GND
Boiler Junction Box
Line Voltage Wiring Connections
Green
White
L2
Service Switch
(Optional)
120V AC
Power
Supply
Black
L1
Power
Supply
120/60/1
DHW
Circulator
Yellow
Red
Thermostat 1 Thermostat 2 Thermostat 3
Thermostat Wires
(Connect into corresponding wires in wiring harness)
Bottom: Yellow wire is 24V AC Positive
System
Circulator
DHW/Zone
Circulator
12
24V AC
X X
R W
R W R W
ISOLATED ZONE 1 ZONE 2 ZONE 3
PRIORITY
END
SWITCH
THERMOSTATS (24V AC)
COM
THREE ZONE SWITCHING RELAY
Remove
Jumper
Between
ZC & 2R
FUSE
5
AMP
120V AC
ZC
ZR
H
H
FUSE
5
AMP
FUSE
5
AMP
FUSE
5
AMP
120V AC CIRCULATORS
ZONE 3
ZONE 1 ZONE 2 PRIORITY
N H N H N H
123
IWH
Aquastat
Control
ZONE 3
PRIORITY
ON
OFF
LED
INDICATORS
POWER
ZONE 1
ZONE 2
ZONE 3
INPUT
120 VAC
N
H
SR 503-4
Explanation:
This arrangement allows the boiler to respond to heating demands and control all the circulators from a zone switching relay.
DHW is controllled by an Aquastat control.
• The zone switching relay end switch wired to the IHC “TT” wires provides a heating demand and energizes the yellow system circulator wire. The IWH Aquastat Control wired to the IHC “1” & “2” terminals provide a DHW demand and
energizes the red DHW/Zone circulator wire.
• A heat demand will energize the yellow wire which will supply voltage to the zone pumps via the “ZC” terminals on the zone
relay. When the DHW demand activates, the IHC will de-energize the yellow system circulator wire and energize the red DHW
circulator. When the DHW demand expires, the IHC will de-energize the red wire and re-energize the yellow wire providing
there is still a call for heat.
• The IHC parameter “dh” must be set to “dh” and when the “Pt” Priority Time parameter is set to “on”, it will prioritize the
IWH without a time out period.
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
53
08/23/13
NOTES
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
54
08/23/13
NOTES
Gas Boiler Wiring & Application Guide
U.S. Boiler Company
55
08/23/13
UNMATCHED
ANYWHERE
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Gas Boiler Wiring & Application Guide
U.S. Boiler Company
56
08/23/13