Medium
AL 28 on Sime Murelle Pro HE 25 HO

Your boiler has locked you out because it was reset too many times in a row while trying to clear a persistent fault.

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

Maximum number of consecutive resets reached (6) — wait 1 hour; attempt reset again; contact Technical Assistance if unresolved

From this model's manual
Verified against the Sime Murelle Pro He 25 Ho installation & service manual, page 32.
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

Wait for 60 minutes without pressing any buttons to allow the lockout timer to expire.Ensure the system pressure is between 1 and 1.5 bar on the pressure gauge.Attempt one single reset of the boiler after the hour has passed.

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