BoilerFaultCodesWhat the manual says
Manufacturer manualIgnition lockout, Overheat lockout, Internal error. Causes: No gas or low gas pressure, Weak spark or spark not across electrodes, Gas valve leaking or failed, Low water pressure or boiler dry, Pump fail, Primary sensor position, Flame sensor fail or connector, Overheat stat tripped or disconnected or faulty, Blocked burner, Blocked heat exchanger, Faulty Harness, Board fault.
Shared across the 24i / 28i Junior range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 27 fault codes on the 24i / 28i Junior
Seeing a different code? Every code this model can display, in one place.