Low
S.88 on Vaillant Home Combi

Your boiler is currently running an automatic process to clear trapped air from its system and does not require any intervention.

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

Product purging active

From this model's manual
Verified against the Vaillant Home Combi installation & service manual, page 35.
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

Wait 5-10 minutes for the automatic cycle to completeMonitor the display to see if it returns to a normal temperature readingEnsure radiators are not making excessive gurgling sounds

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