Low
0 nn on Keston C90 / C110

Your boiler is currently in standby mode because it is not receiving a signal from your thermostat or timer to provide heating or hot water.

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

Module in standby as no heat request from either zone

From this model's manual
Verified against the Keston C90 C110 installation & service manual, page 29.
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 that your heating timer or programme is set to 'On'Turn up the temperature on your room thermostat to see if the boiler fires upEnsure the boiler's own internal temperature or mode settings are currently active

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