BoilerFaultCodesWhat the manual says
Manufacturer manualMaximum ΔT of flow and return sensor in central heating has repeatedly been exceeded. During the block normal operation of the hot water supply is possible. The pump continues to operate at minimum capacity during the block.
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
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