Medium
AL 28 on Sime Dewy 30/130 HE FS

Your boiler has been manually reset too many times in a short period and has temporarily locked itself for safety.

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 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

Stop pressing the reset button immediately.Leave the boiler powered on and wait for exactly one hour without touching the controls.After one hour, the lock-out should clear, allowing one further attempt to reset if the original fault has been resolved.

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