Low
Outside Sensor Fault on Ideal Icos System

Your boiler is struggling because it cannot read the temperature outside, which may cause your heating to work less efficiently or feel inconsistent.

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

Issue with external temperature sensor.

From this model's manual
Verified against the Ideal Icos System 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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