High
6.v on Chaffoteaux Celtic 2 24 Rsc

Your boiler has stopped heating your home because it is struggling to read the temperature correctly, causing it to shut down to prevent overheating.

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 - Heating thermostat faulty (CH only)

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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