Low
H.01.08 on Baxi 436 COMBI 2.1

Your boiler is temporarily pausing because the water inside is heating up much faster than normal.

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

Flow temperature increase in heating mode too quick. Temporary stoppage of 10 minutes.

From this model's manual
Verified against the Baxi/Baxi 400 Combi 2 Baxi400 Comni 2 1 Installation Manual Pdf 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.

DIY fix possible

Check that your radiator valves are fully open to allow water to flow freely.Make sure your heating system pressure is set correctly between 1 and 1.5 bar.Restart the boiler once it has had 10 minutes to cool down.

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Related fault codes

H.01.07View →H.02.58View →E119View →

All 65 fault codes on the 436 COMBI 2.1

Seeing a different code? Every code this model can display, in one place.

254A.00.28A.00.29A.00.34A.02.06A.02.18A.02.36A.02.37A.02.45A.02.46A.02.48A.02.49A.02.54A.02.55A.02.76E.00.04E.00.05E.00.16E.00.17E.00.20E.00.21E.01.04E.01.12E.01.17E.01.20E.02.13E.02.17E.02.35E.02.39E.02.47E.04 | .54E.04.01E.04.02E.04.03E.04.08E.04.10E.04.12E.04.13E.04.17E.04.18E.04.23E.04.29E.04.54E.04.254H.00.42H.00.81H.01.00H.01.05H.01.14H.01.18H.01.21H.02.00H.02.02H.02.03H.02.04H.02.05H.02.07H.02.09H.02.10H.02.70H.03.00H.03.02H.03.05H.03.54

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