Low
58 on Sime Planet Dewy BFR

Your boiler is currently adjusting its internal startup settings and is not reporting a functional error, but rather confirming a configuration state.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Optimisation of switch-on time (0 = off 1 = on)

From this model's manual
Verified against the Sime Planet Dewy Bfr installation & service manual, page 18.
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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