Medium
E04 on Ravenheat Rsf

Your boiler is having trouble measuring the temperature of your hot water, which means you may have no hot water or it may be inconsistent.

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

Domestic hot water (DHW) sensor damaged

Engineer required

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

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Related fault codes

E02View →E03View →

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