High
6.iv on Chaffoteaux Celtic 2 24 Rsc

Your boiler is failing to light the burner because it cannot detect that water is moving through the system to provide heating or hot water.

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

No main burner - Flow switch not operating

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

6.iView →6.iiView →6.iiiView →

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