BoilerFaultCodesWhat the manual says
Manufacturer manualThe control has not detected a water flow. The venting cycle is started. If during this cycle water flow is detected, the venting cycle is ended and the burner is released.
Shared across the Q 25CR 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 53 fault codes on the Q 25CR
Seeing a different code? Every code this model can display, in one place.
Related guides you might find useful
Hot water works but heating does not
On a combi it is usually the diverter valve. On a system boiler, the motorised valve.
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Quarter turn on the valve, wait for water, then check the boiler pressure.
Read →No hot water but heating works
Almost always a stuck diverter valve on a combi.
Read →