IDEAL Logic Code Combi ES26 Installation And Servicing page 54

77 aLTERNa TINg 'F' aND '2' - FLaME LOss
Does the boiler ignite for a short
time and then extinguish?
YES
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
Check siphon and
condensate drain pipe
work for blockage and
rectify if necessary. Boiler
now working OK?
NO
Replace Gas Valve
78 aLTERNa TINg '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?
Is there 230Vac at Blue and Brown connections to the 3 way connection on the Fan?
79 aLTERNa TINg 'F' aND '4' - FLOW ThERMIsTOR FaULT
Is the wiring securely connected to the Flow Thermistor (located in the top of the Heat Exchanger)?
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.
C expect
At 25 o
At 60 C expect
o
At 85
o C expect
Is the Thermistor value correct?
Is there continuity between the PCB and the Thermistor?
54
FaULT FINDINg
Is the Gas Working Pressure avail-
NO
able at the Boiler Inlet (18 mbar)?
Is 215Vdc supply available at the Gas
Valve while the flame is on? (* See note)
Is 230VAC available at spark generator.
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?
* 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.
YES
YES
9,700 - 10,300 Ohms
2,400 - 2,600 Ohms
1,000 - 1,100 Ohms
YES
NO
YES
NO
YES
NO
YES
NO
NO
YES
NO
Fit a new Thermistor
NO
Check and replace wiring as necessary
YES
Replace PCB
Ideal Logic Code Combi ES -
Check gas supply and
rectify fault
Check wiring from gas
valve to PCB for continuity.
If the wiring is OK then
replace the PCB
Replace Spark Generator
and Harness as necessary.
Replace Ignition
Electrode and
associated harness as
necessary
Rectify Wiring &
connections
NO
Replace PCB
Replace Fan
Installation and Servicing