Medium
10.iii on Chaffoteaux Celtic 2 24 Rsc

Your boiler is struggling to maintain a steady temperature, causing it to turn on and off rapidly because water isn't moving through your heating system correctly.

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

Rapid cycling high/low or high/low/off - By-pass if fitted not regulated

Engineer required

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

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Related fault codes

10.iView →10.iiView →

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