Low
D.8 on Vaillant Combi Compact 242EB

Your boiler is currently receiving a signal from your thermostat or external programmer to provide heating.

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.

Technical description

External controls heat demand

DIY fix possible

Check if your room thermostat is set higher than the current room temperatureVerify if your central heating timer or smart app is currently set to an 'On' periodTurn down the thermostat to see if the status code changes, confirming the controls are working

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Related fault codes

D.0View →D.7View →S.4View →

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