High
E20 on Baxi Duo-tec Combi HE

Your boiler's temperature sensor is failing to provide accurate readings, which has caused the system to stop heating your home as a safety precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Central heating return NTC sensor fault

From this model's manual
Verified against the Baxi Duo Tec Combi Ga installation & service manual, page 46.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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