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Ad on Worcester Bosch Greenstar R29 40 HE

Your boiler has identified an issue with the weather compensation sensor, meaning it is currently struggling to automatically adjust its temperature based on the outdoor weather conditions.

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

Outdoor temperature sensor (NTC) faulty (e.g. interruption)

From this model's manual
Verified against the Worcester Bosch Greenstar 25he 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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