High
30 on Johnson Starley Warmaheat

Your boiler has stopped working because its internal thermometer has developed an electrical fault and can no longer monitor the water temperature accurately.

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

Boiler flow temprature sensor short circuit

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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