Low
0 nn on Keston C55

Your boiler is working perfectly and is simply waiting for a signal from your thermostat or hot water timer to start heating your home.

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

Boiler in standby waiting for demand signal

From this model's manual
Verified against the Keston C55 installation & service manual, page 34.
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

Check your room thermostat is set to a higher temperature than the current room temperature.Ensure your heating programmer or timer is set to the 'On' position.Check that any smart heating controls or apps are correctly connected and requesting heat.

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