Low
P.0 on Vaillant ecoTEC exclusive

Your boiler is currently running a self-cleaning routine to remove trapped air bubbles from your pipes and radiators.

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

Bleeding test program: The heating circuit and the hot water circuit are bled via the automatic bleeding valve

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Exclusive 4704437 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.

What causes this fault?

This occurs when air becomes trapped within the boiler's internal heat exchanger or the wider central heating pipework. It is typically triggered automatically after the system has been drained for a repair or when the water pressure has recently been topped up, as new water introduces small air bubbles into the system.

This is most common in autumn when homeowners turn their heating back on for the first time or after summer maintenance work has been completed.

DIY fix possible

Wait approximately 6.5 minutes for the program to finish automaticallyEnsure your radiator valves are open to allow air to moveCheck your boiler pressure once the cycle ends and top up if it has dropped below 1.2 bar

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Avoid the next call-out bill

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Related fault codes

All 71 fault codes on the ecoTEC exclusive

Seeing a different code? Every code this model can display, in one place.

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