Medium
66 on Sime Planet Dewy BFR

Your boiler is struggling to read the temperature from an external sensor, which is preventing it from heating your home correctly.

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

External and ambient sensor influence

From this model's manual
Verified against the Sime Planet Dewy Bfr installation & service manual, page 19.
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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