Emergency
Pump runs on Worcester Bosch 28 RSF

Your boiler has sensed that it is dangerously overheating and is running the pump constantly to try and cool itself down.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Primary temperature 115°C

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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