Medium
F10 on Ideal Logic Air

Your boiler's external sensor is struggling to communicate, which means the system cannot accurately measure the outdoor temperature to adjust your heating effectively.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Outdoor heatsink thmr fault

From this model's manual
Verified against the Ideal Logic Air 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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