Medium
59 on Sime Dewy 30/50 HE WM

Your boiler has detected that the temperature is rising too quickly or unevenly, suggesting a potential circulation issue within your heating 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

Heating gradient

From this model's manual
Verified against the Sime Dewy 30 50 He Wm installation & service manual, page 16.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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