56
FAULT FINDING
F
AUL
T FINDING F
AUL
T FINDING F
AUL
T FINDING F
AUL
T FINDING F
AUL
T FINDING
Installation and Servicing
74
ALTERNATING ‘L’ AND ‘6’ - FALSE FLAME LOCKOUT
75
ALTERNATING ‘F’ AND ‘1’ - LOW WATER PRESSURE
76
ALTERNATING ‘F’ AND ‘2’ - FLAME LOSS
Does the boiler ignite for a short
time and then extinguish?
YES
Is the Gas Pressure available at
the Boiler Inlet (18 mbar)?
Check the detection electrode and
associated harness for: continuity,
visual condition and position (Refer
to Frame 49). Check if condensate
pipe is blocked. Check if flue is
blocked.
Replace as necessary
NO
Check gas supply and
rectify fault
NO
YES
Is 215Vdc supply available at the
Gas Valve while the flame is on?
(* See note)
YES
Check spark generator and
associated harness for: continuity
and visual condition. (Refer to
Frame 50) Are these functioning
correctly?
YES
Check ignition electrode and
associated harness for: continuity,
visual condition and position.
(Refer to Frame 48) Are these
functioning correctly?
YES
Check siphon and condensate
drain pipe work for blockage and
rectify if necessary. Boiler now
working OK?
Check wiring from gas
valve to PCB for continuity.
If the wiring is OK then
replace the PCB
NO
Replace Spark Generator
and Harness as necessary.
NO
Replace Ignition
Electrode and
associated harness as
necessary
NO
Replace Gas Valve
NO
* Note:
due to the wave form of the rectified
voltage, the reading will vary depending
on the type of meter used to measure the
value. In general terms a reading greater
than 150V indicates that the correct voltage
is supplied to the gas valve.
Restart the boiler, does Boiler Work OK?
NO
Check routing and integrity of internal boiler wiring is OK. Check
condition of Flame Sense Electrode and replace if deteriorated.
Separate the flame detection electrode in-line connector. Is there
continuity between the terminals pins connected to the electrode?
YES
Replace Flame Detection Electrode
Check routing and integrity of internal boiler wiring
YES
NO
RESET PROCEDURE
- To restart boiler, turn mode knob to restart position and immediately turn knob back to required setting.
Are the Boiler and CH System filled with water and all isolation and
radiator valves open (check pressure gauge is between 1 to 1.5 bar)?
NO
NO
YES
Fill and vent the system and open all
isolation valves
YES
Are connections on water pressure sensor secure?
Re-fit connections
Replace water pressure sensor
Summary of Contents for ULTRA COMBI 35
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