BoilerFaultCodes.com
31 High

Your boiler has lost its connection with the thermostat or control panel, meaning it cannot receive instructions to turn on or off.

Technical description: Loss of communication with external control (Alpha Climatic)
Typical repair cost: £90-180 (including labour)

DIY fix possible

Check if the batteries in your Alpha Climatic room thermostat need replacing.Ensure the thermostat is within range of the boiler and has not been moved.Try restarting the boiler using the reset button to refresh the connection.

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Parts commonly replaced

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