BoilerFaultCodesYour boiler has lost connection with its indoor temperature sensor, meaning it can no longer tell how warm your rooms are and has switched to a basic backup heating mode.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Control mode without room influence - Room temperature sensor heating circuit A1 lead break
What causes this fault?
This fault occurs when the communication link between your boiler and the internal room thermostat is broken, usually due to a damaged sensor or a loose connection in the wiring. The most common reason is that the delicate electronic components inside the temperature sensor have failed over time, or the wires connecting it to the boiler's control board have become frayed or disconnected.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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