BoilerFaultCodes.com
1-C4 Low Information

Your boiler is displaying the current outdoor temperature because an external weather sensor is connected, which is a normal status reading rather than a breakdown.

Monitor it

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: Outside temperature: Current outside temperature (with outside temperature sensor connected)

What causes this fault?

This code appears because your heating system has an optional weather compensation sensor installed on the outside of your property. It acts as an information display rather than a mechanical failure, simply showing the boiler's reading of the current air temperature. This allows the boiler to automatically adjust its efficiency based on how cold it is outside.

Typical repair cost £0 (including labour)

DIY fix possible

Check if the display returns to the normal temperature screen automaticallyPress the 'Back' or 'Reset' button once to clear the informational messageEnsure the external sensor is not obstructed by snow or debris

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