Download Bryant 558D User's Manual

PRE-START-UP
START-UP
I. HEATING SECTION START-UP AND ADJUSTMENTS
WARNING: Failure to observe the following warnings could result in serious personal injury:
1. Follow recognized safety practices and wear protective goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric
power to unit unless compressor terminal cover is
in place and secured.
3. Do not remove compressor terminal cover until all
electrical sources have been disconnected.
4. Relieve all pressure from system before touching
or disturbing anything inside terminal box if
refrigerant leak is suspected around compressor
terminals.
5. Never attempt to repair soldered connection while
refrigerant system is under pressure.
6. Do not use torch to remove any component. System contains oil and refrigerant under pressure.
To remove a component, wear protective goggles
and proceed as follows:
a. Relieve all pressure from system.
b. Cut component-connecting tubing with tubing
cutter and remove component from unit.
c. Carefully unsweat remaining tubing stubs when
necessary. Oil can ignite when exposed to torch
flame.
CAUTION: Complete the required procedures given
in Pre-Start-Up section on this page before starting unit.
Do not jumper any safety devices when operating the unit.
A. Checking Heating Control Operation
Start and check the unit for proper heating control operation
as follows:
1. Turn on unit electrical supply.
2. Set system switch selector at HEAT position and fan switch
at AUTO. or ON position. Set heating temperature
lever above room temperature.
3. The evaporator fan will start immediately, and electric
heater will be energized.
4. Check for heating operation by verifying that unit supply outlets are functional.
5. The evaporator fan and heaters will turn off after thermostat temperature is satisfied.
Proceed as follows to inspect and prepare the unit for initial
start-up:
1. Remove all access panels.
2. Read and follow instructions on all WARNING, CAUTION and INFORMATION labels attached to, or shipped
with, unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages such as
broken lines, loose parts, disconnected wires, etc.
b. Inspect for oil at all refrigerant tubing connections
and on unit base. Detecting oil generally indicates a
refrigerant leak. Leak-test all refrigerant tubing connections using electronic leak detector, halide torch,
or liquid-soap solution. If refrigerant leak is detected, see Refrigerant Leaks section on page 30.
c. Inspect all field- and factory-wiring connections. Be
sure that connections are completed and tight.
d. Inspect coil fins. If damaged during shipping and handling, carefully straighten fins with a fin comb.
4. Verify the following conditions:
a. Make sure that condenser-fan blade is positioned correctly in fan orifice. Blades should clear fan motor
and fan orifice ring.
b. Make sure that air filters are in place.
c. Make sure that condensate drain pan and trap are
filled with water to ensure proper drainage.
d. Make sure that all tools and miscellaneous loose parts
have been removed.
5. Compressors are internally spring mounted. Do not loosen
or remove compressor holddown bolts.
6. Each unit system has 4 Schrader-type gage ports: one
on the suction line, one on the liquid line and two on
the compressor discharge line. Be sure that caps on the
ports are tight.
Unit is now ready for initial start-up.
B. Heating Sequence of Operation
Room thermostat calls for heat, closing circuit between R and
W1 24-v control terminals. Power to terminal R is supplied
through the 24-v transformer, which is internally protected
against overload. The 24-v power energizes the indoor (evaporator) fan relay (IFR). The IFR closes normally open contacts
2 to 4, which energize the indoor (evaporator) fan contactor
(IFC) and the electric heat contactor, and start the indoor (evaporator) fan motor (IFM). There is no time delay in the start-up
of the IFM.
When the call for heat is satisfied, then the R to W1 circuit is
opened and the IFR and IFC are deenergized.
Additional information on economizer operating in the heating only mode is provided in Ventilation Sequence section on
page 27.
C. Limit Switches
The heating limit switches (LS) are normally closed. If the
leaving-air temperature exceeds the maximum allowable temperature, one of the limit switches will open, breaking the
power circuit to the heater. This causes the heater to shut
down immediately. Check the air quantity to ensure there is
sufficient airflow.
If unit does not energize, reset the normally closed manual
limit switch (LSM). The LSM reset button is located on the
fan housing, and will only open in the event of a fan failure.
D. Airflow and Temperature Rise
The heating operation airflow must produce a temperature
rise that falls within the approved cfm range (300 to 500 cfm
per 12,000 Btuh cooling).
Refer to Indoor Airflow and Airflow Adjustments section on
page 19 to adjust heating airflow where required.
E. Safety Check of Limit Control
A manual reset limit control is located on the evaporator fan.
The control shuts off the unit in the event of fan failure.
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