Low
S.02 on Vaillant ecoTEC plus aquaPLUS

Your boiler is currently warming up your radiators as part of its normal heating 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

Pump running (heating operation)

From this model's manual
Verified against the Vaillant Ecotec Plus Aquaplus installation & service manual, page 38.
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 your thermostat or programmer settings to see if heating is requestedMonitor the display to see if the code changes to S.04 once the boiler fires upNo action is required if your radiators are getting warm as expected

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Related fault codes

S.00View →S.01View →S.03View →S.04View →

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