BoilerFaultCodes OT ERROR Medium
Your boiler's external temperature sensor and frost protection thermostat are sending conflicting signals to your heating controller.
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.
Typical repair cost £120-200 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like OT ERROR — no call-out fees, no surprises.
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