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/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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Related fault codes

01View →02View →06View →

All 67 fault codes on the Dewy 30/50 HE WM

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

0 bar1 bar3 bar51525354555657586061626364656669AL 01AL 02AL 03AL 04AL 05AL 06AL 07AL 08AL 09AL 10AL 11AL 12AL 13AL 14AL 15AL 17AL 18AL 28AL 30AL 37AL 40AL 41AL 42AL 43AL 44AL 56AL 57AL 62AL 72AL 74AL 77AL 78AL 79AL 80AL 81AL 82AL 83AL 84AL 88AL 89AL 90AL 92AL 93AL 95AL 96AL 98AL 99

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