Medium
F52 on Johnson Starley Optima E20

Your boiler's temperature sensor for hot water has stopped working properly, which means you might not get any hot water from your taps.

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 fault

Engineer required

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

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