High
5.iv on Chaffoteaux Celtic 24 HE

Your boiler is struggling to heat your water at the correct temperature because an internal component responsible for controlling air flow is the wrong type for this specific model.

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 - Incorrect venturi fitted

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 →

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