High
D4 213 on Worcester Bosch Hideaway

Your boiler is shutting down because it is heating up much faster than it should, which usually means the water isn't moving through the system properly.

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 actual temperature recorded by the flow temperature sensor or return temperature 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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