Download Viessmann Vitodens 100 WB1A Specifications

Störungsbehebung
Fault finding
General
Hinweis
It is the law that any service work
must be carried out by a competent
CORGI registered engineer.
Before looking for a fault condition,
check that:
& The mains electrical supply is turned on.
& The clock and / or room thermostat
(if fitted) are calling for heat (CH
‘faults’ only).
The gas service cock is open.
The DHW (Combi only) and CH isolation cocks are open.
& The system is at design pressure.
Before attempting any electrical fault
finding, always conduct the preliminary electrical system safety checks.
On completion of any service or fault
finding operation involving making or
breaking electrical connections
always check for earth continuity,
polarity and resistance to earth.
&
&
Function sequence and possible faults
Display screen
No
Control unit issues heat demand
Remedy
Increase set value
and ensure heat is
drawn off
Yes
Fan starts
No
after approx. 51 s
Fault
F5/F9
No
after approx. 51 s
Checking fan cables and plugs
Yes
Air pressure limiter enables
start (contact
closed between
terminals „X8.7“
and „X8.8“)
Fault
F5/F9
Check fan cables
and fan plug-in
connections,
check fan
Ignition
No
Fault
F4
66
Check the connection ignition
module
5851 670
Yes