Medium
46 on Alpha E-Tec 33

Your boiler has lost the connection to your room thermostat, meaning it doesn't know when to turn your heating on or off.

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

No continuity of optional thermostat circuit

DIY fix possible

Check your room thermostat has fresh batteries and is switched onEnsure the thermostat is communicating with the receiver unitCheck that any external time clock or programmer is set to 'On' and hasn't had a power cut

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