Low
d.23 on Vaillant Home Combi

Your boiler is currently operating exactly as it should and is simply waiting for a signal from your thermostat to provide heat 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

Statusoftheheatingdemand

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 32.
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 temperatureEnsure your heating timer is currently set to an 'ON' periodCheck the hot water tap is turned on fully if you are expecting hot water

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d.21View →d.22View →

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