Medium
H.01 – .21 on Baxi Suprima 50

Your boiler is shutting down because the water inside is heating up too quickly, which usually means it isn't moving through the system properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Temporary error – flow temperature increasing too fast in domestic hot water (DHW) mode, insufficient circulation or sensor error.

DIY fix possible

Check that your home's radiator valves and any isolation valves are fully openBleed your radiators to remove any trapped air pocketsMonitor the boiler to see if it resets automatically once the temperature drops

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