Medium
b 38 on Ideal Imax W

Your boiler is struggling to detect the temperature of your hot water cylinder because there is a loose or broken wire connection.

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

Tank sensor open circuit

Engineer required

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

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