Medium
59 on Sime Planet Super 4 WM

Your boiler is struggling to heat the water at the expected speed, likely due to a poor connection or an internal sensor failing to register the temperature increase.

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 Planet Super 4 Wm installation & service manual, page 14.
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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