IDEAL Logic HEAT 12, Installation And Servicing

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53
Fault Finding
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Ideal Logic Heat -
Installation and Servicing
67 aLTERNaTINg ‘L’ aND ‘1’ - FLOW TEMpERaTURE OVERhEaT LOCKOUT
Is the Boiler and CH System filled with water and all
isolation and radiator valves open?
yES
Fill and vent the system and open all isolation valves,
then restart boiler
Is Flow/Return Differential across Boiler in excess of 30°C?
NO
Check that the Pump is rotating freely.
Is the Differential now below 20°C?
yES
Check the Flow Thermistor (Refer to Frame 55)
Replace the Pump,then restart boiler
NO
OK, now
restart boiler
68 aLTERNaTINg ‘L’ aND ‘2’ - IgNITION LOCKOUT
If the boiler is restarted 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 57).
Check if the condensate pipe is
blocked.
Check flue is installed correctly.
Replace as necessary
NO
Check gas supply and
rectify fault
NO
yES
Is 215Vdc supply available at the
Gas Valve? (* See note)
yES
Check spark generator and
associated harness for: continuity
and visual condition. (Refer to
Frame 58) Are these functioning
correctly?
yES
Check ignition electrode and
associated harness for: continuity,
visual condition and position.
(Refer to Frame 56) Are these
functioning correctly?
NO
Check siphon and condensate
drain pipe work for blockage and
rectify if necessary. Boiler now
working OK?
Check wiring connection
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
yES
* 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.
Unplug gas valve. Is resistance
between outside pins 4K
Ω
(±2)?
yES
Replace Gas Valve
NO
REsTaRT pROCEDURE - To restart boiler, turn mode knob to restart position and immediately turn knob back to required setting.
REsTaRT pROCEDURE - To restart boiler, turn mode knob to restart position and immediately turn knob back to required setting.
NO
yES
69 aLTERNaTINg ‘L’ aND ‘6’ - FaLsE FLaME LOCKOUT
Restart the boiler, does Boiler Work OK?
NO
Check routing and integrity of internal boiler wiring is OK. Check
condition of Flame Sense Electrode, 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
REsTaRT pROCEDURE - To restart boiler, turn mode knob to restart position and immediately turn knob back to required setting.