IDEAL Logic SYSTEM 15 Installation And Servicing page 49

64 aLTERNaTINg 'L' aND '1' - FLOW TEMpERaTURE OVERhEaT LOCKOUT OR NO
WaTER FLOW LOCKOUT
Is the Boiler and CH System filled with water and all
isolation and radiator valves open?
If the PCB has been replaced check a BCC has been
fitted then reset the boiler.
Is the Flow/Return Differential across the Boiler in
excess of 30°C?
Check the Control/No Water Flow and Return
Thermistors (Refer to Frame 48 & 59)
REsET pROCEDURE - To reset boiler, turn mode knob to reset position and immediately turn knob back to required setting.
65 aLTERNaTINg 'L' aND '2' - IgNITION LOCKOUT
If the boiler is reset 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 47).
Check if the condensate pipe is
blocked.
Check flue is installed correctly.
Replace as necessary
Check siphon and condensate
drain pipe work for blockage and
rectify if necessary. Boiler now
working OK?
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.
REsET pROCEDURE - To reset boiler, turn mode knob to reset position and immediately turn knob back to required setting.
Ideal Logic System -
Installation and Servicing
Fault Finding
YES
NO
NO
Is the Gas Pressure available at
the Boiler Inlet (>18 mbar)?
Is 215Vdc supply available at the
Gas Valve? (* See note)
Unplug gas valve. Is resistance
between outside pins 4KΩ (±2)?
Check spark generator and
associated harness for: continuity
and visual condition. (Refer to
Frame 48) Are these functioning
correctly?
Check ignition electrode and
YES
associated harness for: continuity,
visual condition and position.
(Refer to Frame 46) Are these
functioning correctly?
NO
Fill and vent the system and open all
isolation valves, then reset boiler
YES
Check that the Pump is rotating freely. Is
the Differential now below 20°C?
NO
Replace the Pump,
then reset boiler
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
OK, now
reset boiler
Check gas supply and
rectify fault
Check wiring connection
from gas valve to PCB for
continuity. If the wiring is
OK then replace the PCB
Replace Gas Valve
Replace Spark
Generator and harness
as necessary
Replace Ignition
Electrode and
associated harness as
necessary
49