High
5.vii on Chaffoteaux Celtic 24 HE

Your boiler is struggling to provide consistent hot water because a safety sensor is failing to stay in the correct position while the water is running.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Hot water does not operate over temperature range - Pressure switch hunting

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

5.vView →6.iView →6.iiView →

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