Low Information
S.1 on Vaillant ecoMAX 828E

Your boiler is currently working as normal to pump heat through your radiators and does not have a fault.

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.

Technical description

Pump running (heating operation)

What causes this fault?

This code is actually a status indicator rather than a breakdown, appearing when the boiler is actively circulating hot water to your radiators. It shows that the internal pump is operating correctly to move heat from the unit into your home. You will typically see this on the display whenever your thermostat is calling for heat and the system is functioning as intended.

This code is most frequently seen during the autumn and winter months when the central heating is used daily to keep the property warm.

DIY fix possible

Check your thermostat to see if it is calling for heatMonitor the display to see if the code changes once the house reaches temperatureNo action is required as this is an operational status message rather than an error

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