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Sales/Spares & Replacement Help Line 01604 762881
SENSOR STUCK LOCKOUT
RETURN THERMISTOR FAULT
FLOW/RETURN SENSOR CALIBRATION CHECK
VALVE FEED BACK ERROR
EEPROM LOCKOUT
ADC LOCKOUT
FLAME CIRCUIT FAILURE
YES
YES
YES
YES
YES
YES
YES
YES
Replace the PCB.
Check resistance at 2 different temperatures. See Graph Figure 51.
Replace the PCB.
Does the flow pipe temperature increase by more than 1°C within 30
seconds of ignition?
NO
NO
NO
NO
NO
NO
NO
NO
NO
Fit a new Thermistor.
Fill and vent the system and open all isolation
valves, check as supply, then reset boiler
Replace Gas Valve.
Fill and vent the system and open all isolation
valves, check as supply, then reset boiler
Check and replace wiring as necessary.
Replace the Flow/Return Sensor.
Secure Sensors and reset.
Replace Sensor.
Check pump is rotating.
Remove the return thermistor from the CH return pipe and disconnect the
wires. Check the resistance using a suitable multi-meter connected across
the thermistor’s terminal pins. Is the thermistor valve correct?
Is the boiler & CH system filled with water & all isolation valves open?
Unplug the Gas Valve. Is there resistance between pins 114
Ω
.
Replace the PCB.
Replace the PCB.
Replace the PCB.
Is the boiler filled with water and all isolation valves open?
Is the wiring securely connected to the low voltage 9 way connector X5 on
the PCB?
Reset the boiler. Is the boiler working?
Replace Board.
Are the sensors secured firmly to the flow and return pipes?
