56
FaULT FINDINg
F
a
UL
T FINDIN
g
F
a
UL
T FINDIN
g
F
a
UL
T FINDIN
g
F
a
UL
T FINDIN
g
F
a
UL
T FINDIN
g
Ideal Logic Code Combi -
Installation and Servicing
84 aLTERNaTINg ‘F’ aND ‘2’ - FLaME LOss
Does the boiler ignite for a short
time and then extinguish?
YES
Is the Gas Working Pressure avail-
able at the Boiler Inlet (18 mbar)?
Check the detection electrode and
associated harness for: continuity,
visual condition and position (Refer to
Frame 55). 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
Is 230VAC available at spark generator.
Check spark generator and associated
harness for: continuity and visual
condition. (Refer to Frame 56) Are these
functioning correctly?
YES
NO
Check ignition electrode and associated harness
for: continuity, visual condition and position. (Refer
to Frame 54) 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
* 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.
85 aLTERNaTINg ‘F’ aND ‘3’ - FaN FaULT
Does the wiring from the Fan to the PCB have secure connections at both ends
and has not deteriorated? Does the wiring have continuity?
YES
YES
Rectify Wiring &
connections
Is there 230Vac at Blue and Brown connections to the 3 way connection on the Fan?
NO
Replace PCB
NO
Replace Fan
86 aLTERNaTINg ‘F’ aND ‘4’ - FLOW ThERMIsTOR FaULT
Remove the Flow Thermistor from the CH Flow Pipe
and disconnect the wires.
Check the resistance using a suitable multimeter
connected across the thermistor’s terminal pins.
At 25
o
C expect
9,700 - 10,300
Ohms
At 60
o
C expect
2,400 - 2,600
Ohms
At 85
o
C expect
1,000 - 1,100 Ohms
Is the Thermistor value correct?
YES
Is there continuity between the PCB and the Thermistor?
Replace PCB
Fit a new Thermistor
NO
Check and replace wiring as necessary
NO
YES
206279-1.indd 56
06/01/2011 09:10:49
Summary of Contents for LOGIC Code Combi 26
Page 2: ...2 Ideal Logic Code Combi Installation and Servicing ...
Page 61: ......
