Medium
H 3 on Ideal Isar System

Your boiler is struggling to accurately detect the temperature of your hot water, which means it may fail to provide a consistent supply or stop heating your water altogether.

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

ALTERNATING 'H' '3' GO TO FRAME 92

Engineer required

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

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