Low
Outside sensor on Ideal Concord CXA 40-120

Your boiler is struggling because it has lost the signal from the temperature sensor installed on the outside of your property, which tells it how hard to work based on the weather.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

Outside sensor fault (if fitted)

From this model's manual
Verified against the Ideal Concord Cxa 40 120 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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