Medium
P33 on Alpha Intec 50CS

Your boiler is failing to switch off when the house reaches the target temperature, meaning your radiators will stay on until you manually turn the boiler down.

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

The optional environment thermostat (TA) not working, the boiler functions all the time in central heating mode. (Can be activated through the 'Customisation' menu. It allows activation of the central heating even if the TA is out of order).

DIY fix possible

Check and replace the batteries in your room thermostatEnsure the thermostat is within wireless range of the boilerEnter the 'Customisation' menu on the boiler display to manually control the heating until the thermostat is fixed

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