Fault Finding - IDEAL SUPER PLUS 200/S Installation And Servicing

FAULT FINDING

MODULE 'MAINS ON' LIGHT NOT
ILLUMINATED
Check that:
i) External fuses are intact and that the external controls are
calling for heat.
ii) There is mains electrical supply (230V) at both S3 terminals
on PCBs 10 and 11 in the wiring centre (see Fig.14 ), and that
the wiring centre fuses and connections are sound.
iii) All connections are sound in the module multipin plug and in the
control box; there is mains electrical supply (230V) at terminals
2 and 4 in the multipin plug (Fig.14)
Replace parts (as appropriate) PCBs 11, 10, 15 or 9.
FAN DOES NOT START
Check that:
i) Module thermostat is calling for heat. Note that at any particular
time the return water temperature may be higher than the
individual module thermostat setting; module is not out on
overheat if so press in overheat reset button and see Fault
Finding No.8)
ii) There Is electrical continuity between the brown and blue
pressure switch connections (note that these wires carry 230V);
pressure and suction lines and connections are sound.
ill) There is mains electrical supply (230V) to the fan motor and
that fan impeller is free to rotate (note that the fan motor is fitted
with a thermal trip, so if impeller is jammed, free it and allow
time for the motor to cool)
iv) Connections are sound in the control box
Replace parts (as appropriate) fan motor, PCB 9B, pressure switch
and thermostat sensor.
IGNITION SEQUENCE DOES NOT START
Check that:-
i) The normal boiler operation is that where no modules are firing,
all module fans will start and run for a minimum of 70 seconds
and then, depending on the module's position in the firing
sequence, the fan will stop for a delay varying between 0 second
and 35 seconds, after which the fan will run for approximately a
further 35 seconds. Only then will the ignition sequence start.
ii) The 'lockout' light is not illuminated: if it is wait for 15 seconds
and then press in and release the lockout reset button.
iii) All connections are sound at the control box and the pressure
switch, and that the fan is operating.
iv) The pressure switch differential pressure is >5.5 mb. If not check
the fan impeller, cast venturi, pressure and suction lines, burner,
module heat exchanger or flue for blockage or leakage.
v) There is electrical continuity between the blue and black
pressure switch connections (note that these wires carry 230V)
vi) The flame probe circuit has not shorted to earth. Replace parts
(as appropriate). Pressure switch, flame probe, PCBs 9B and
12.
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FAULT FINDING
NO SPARK AT IGNITION ELECTRODE
Check that:
i) The ignition electrode and lead are sound and that all
connections are clean and tight and there is no arcing anywhere
but at the spark gap.
ii) The electrode spark gap is 3.5 ± 0.5 mm (Fig.l7)
iii) There is mains electrical supply (230V) at the spark generator
at the correct time during the ignition sequence (Fig. 19)
Replace parts (as appropriate) spark generator, ignition electrode
and feed or PCBs 13, 12, or 9B
MAIN BURNER DOES NOT STAY ALIGHT
Check that:
i) The pilot flame detector current is approximately 6µA by
breaking the inline connector in the flame detector lead and
inserting a micro-ammeter.
ii) That all connections are sound in the control box and flame
detector lead.
iii) The flame detector and electrode is sound and correctly
connected.
Replace parts (as appropriate) flame detector electrode and flyaway
lead, flame detector lead, PCBs 13, 12 or 9B or main burner
complete with pilot pipe.
MAIN BURNER DOES NOT LIGHT
Check that:
i) Main burner pressure is 2.7 mbar, and that main burner injector
is clean and undamaged.
ii) There is mains electrical supply (230V) at both main gas valves
and that both gas valves are open.
iii) There is a minimum dynamic gas inlet pressure available.
Replace parts (as appropriate) main gas governor, main gas valves,
PCBs 12 or 9B or main gas injector.
MODULE OUT ON OVERHEAT
Check that:
i) Water temperature difference across module when it is firing
is 10 - 12 C. Adjust water flow rate as necessary.
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ii) Main thermostat sensor is pushed fully home in its pocket and
is secured with its retaining clip.
iii) Overheat thermostat is operating at its correct setting of 100
Replace parts (as appropriate) overheat thermostat, control
thermostat sensor, control thermostat potentiometer or PCB 9B.
Super Plus -
Installation and Servicing
C.
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