High
NO CODE 212 on Worcester Bosch Heatslave

Your boiler is shutting down because it is heating up much faster than it can move the water around the system, often due to a blockage or a pump issue.

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 or flow temperature rising too fast

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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