Medium
H.01.08 on Baxi Assure System

Your boiler has paused heating because the water is heating up faster than expected, likely due to a restriction in the system.

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

INSUFFICIENT CIRCULATION Flow temperature increase in heating mode too quick. Temporary stoppage of 10 minutes. Check the boiler/installation circulation Activate a manual venting cycle Check the installation pressure Check the cleanliness of the exchanger Check the operation of the temperature sensors Check the temperature sensor connection

From this model's manual
Verified against the Baxi Bm Baxi B Basic System 2 600 800 Assure 500 Isim installation & service manual, page 48.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check that all radiator valves throughout your home are fully openEnsure your system pressure gauge is reading between 1.0 and 1.5 barBleed your radiators to remove any trapped air that might be blocking water flow

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