Low
d.00 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently running at a lower power setting than its maximum capacity, which is a normal operational adjustment rather than a breakdown.

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

Part load setting

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

Check that your radiators are turned upEnsure your thermostat is calling for heatMonitor the boiler as it will likely exit this status automatically once demand increases

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Related fault codes

d.01View →d.02View →

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