Low
d.30 on Vaillant ecoTEC plus aquaPLUS

Your boiler's control system is checking whether the gas valve is open or closed, which is part of its normal safety process.

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

Gas valve status

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual.
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

No action required; this is an information code, not a faultMonitor the display to see if it changes to a standard temperature readingIf the boiler is not firing, try a simple reset

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Related fault codes

F.28View →F.29View →d.33View →

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