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

Shared across the Murelle Pro HE 25 HO range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

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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Related fault codes

AL02View →AL05View →AL06View →

All 27 fault codes on the Murelle Pro HE 25 HO

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

AL 01AL 02AL 03AL 04AL 05AL 06AL 07AL 08AL 09AL 10AL 11AL 12AL 13AL 14AL 15AL 18AL 37AL 40AL 41AL 42AL 43AL 62AL 72AL 81AL 83AL 96

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