Medium
D.78 on Vaillant Combi Compact 282EB

Your boiler is limiting the temperature it uses to heat your hot water, likely because it has detected a measurement error or an overheating risk in the storage cylinder.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Limitation of cylinder charging temperature in c

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.23View →F.24View →

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