Medium
65 on Sime Planet Super 4 WM

Your boiler is receiving an conflicting signal from an external accessory, such as a weather sensor or an external timer, which is preventing it from firing normally.

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

Operating mode of external contact

From this model's manual
Verified against the Sime Planet Super 4 Wm installation & service manual, page 15.
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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