Low
53 on Sime Dewy 30/130 HE FS

Your boiler is displaying a configuration message indicating how it communicates with your room thermostat, rather than a mechanical breakdown.

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

Type of control: 0 = with ambient influence 1 = without ambient influence

From this model's manual
Verified against the Sime Dewy 30 130 He Fs installation & service manual, page 17.
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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