Select a fault code
System pressure has dropped below minimum operating level.
Failed to ignite after multiple attempts.
Flame extinguished unexpectedly during operation.
Gas valve not closing or wiring fault.
Pressure sensor sending implausible reading.
No pressure change on pump start.
Condensate pump or pipe blocked.
No temperature rise detected when burner started — possible flow issue.
The boiler failed to light. Common causes include low gas pressure, a dirty electrode, or a blocked condensate pipe.
System pressure below minimum operating level.
Flow temperature rising too rapidly, indicating circulation problem.
Ignition was attempted but no flame was established.
The flame went out during normal running.
Fan not operating at the required speed for safe combustion.
Gas pressure at the boiler is below the minimum required.
Gas valve relay fault detected.
EEPROM fault on the main PCB.
The water pressure sensor has failed.
No pressure change detected when pump starts. Indicates pump failure or sensor fault.
Condensate cannot drain — blocked or frozen pipe.
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