Low
d.16 on Vaillant Home Combi

Your boiler is receiving a signal from your thermostat that it is not currently calling for heat.

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

Statusofthe24Vroomthermostat

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 31.
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 wall-mounted thermostat or app to ensure it is set to a temperature higher than the current room temperatureEnsure the batteries in your room thermostat are not deadCheck if your thermostat is currently in a scheduled 'off' or 'away' mode

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Related fault codes

d.15View →d.17View →

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