High
7 flashes on Worcester Bosch Greenstar 25CDi

Your boiler has overheated because the water inside is not moving correctly or has become too hot, causing a safety sensor to shut the system down.

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

Safety temp. limiter in CH flow has tripped. Check system pressure, check safety temp. limiters, check pump operation, check fuse on pcb, bleed appliance.

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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