High
212 on Worcester Bosch Hideaway

Your boiler is overheating because the water inside is heating up too fast, often due to a pump failure or a blockage preventing water from moving through the system.

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

The temperature recorded by the flow temperature sensor or the safety sensor is rising too quickly

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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Related fault codes

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