High
6.ii on Chaffoteaux Celtic 2 24 Rsc

Your boiler is failing to start because the internal pump, which is responsible for moving water through your heating system, is stuck or blocked.

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 - Pump jammed

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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