Low
51 on Sime Dewy 30/130 HE FS

Your boiler has detected that the water inside the system is getting too cold and has activated its built-in safety mode to prevent the pipes from freezing.

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

Antifreeze protection

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.

DIY fix possible

Ensure the boiler is switched on and the power supply is not interrupted.Check that the thermostat is calling for heat to allow the pump to circulate water.If the weather is extremely cold, leave the heating on a low constant setting to keep the internal pipes warm.

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