High
é0 on Remeha Avanta

Your boiler has stopped working because one of its internal temperature sensors is providing faulty data, preventing the system from safely heating your home.

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

Flow or return sensor fault. Short circuit in the flow, return or boiler temperature sensor. Defective or not (properly) connected flow, return or boiler temperature sensor.

From this model's manual
Verified against the Remeha Avanta 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 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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