Medium
OT ERROR on Remeha Avanta 28c

Your boiler's external temperature sensor and frost protection thermostat are sending conflicting signals to your heating controller.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

Outside sensor used in conjunction with a frost thermostat connected parallel to the Celcia on connectors 7 and 8 on X9; when the frost thermostat calls for heat (contact closed) it will override the Celcia 20 control.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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