Excel HE C24, Руководство пользователя

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50
FAULT FINDING
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excel HE -
Installation and Servicing
81 ERROR CODE 2 - OVERHEAT ALARM
80 ERROR CODE 1 - LOCKOUT
Causes:
Failed to light after 5 ignition attempts or after
flame failure.
Does the boiler light then
go out?
Check gas supply and
rectify
Is 20 mbar pressure
available at the inlet?
NO NO
Check detection electrode
and wiring for continuity,
condition and position.
Replace if necessary
YES YES
Is 240V AC available
between L(3) and N(1) at
the NAC connection with the
Gas Valve?
Check NAC wiring for
continuity. Is it OK?
NO
Is 240V AC available
at the PCB?
NO
YES
Is there a spark?
Replace PCB
Replace Gas Valve
YES
NO
Is 240V AC available at the
PCB for the NAC?
Replace PCB
NO
YES
Replace NAC
Replace ignition electrodes
NO
YES
YES
NO
Replace NAC
Can the error be reset by the
reset procedure when the
boiler is cold? (See Frame 39)
NO
NO
YES YES
NO
YES
Replace OH Stat
Replace wiring harness Is wiring continuity OK?
Replace PCB
YES
Set CH control knob to max
temperature. If the OH trips
again measure flow temp:
Over 90
o
C - check flow
thermistor (Frame 72 & 84)
Under 90
o
C - replace O/H stat.
YES
Fill and vent system and
open all isolation valves
NO
Replace pump
NO
Check:
- Gas Flow
- Spark
- Detection
Check ignition electrodes
for continuity, condition and
position. Are they both OK?
Is voltage across OH stat
0V dc?
When the boiler is fired does
the pump give a differential
across the heat exchanger inlet
and outlet of 10
o
C to 30
o
C?
N L N
Are the boiler and system
filled and all isolation
valves open?
Note.
Air pressure switch failure results in 5 -
Code 4 cycles followed by Error Code 1.