Low
Filling on Viessmann Vitodens 050-W

Your boiler is currently in the process of being filled with water, and the control system is waiting for the pressure to reach the correct level before it can start working again.

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

Whilst filling is in progress (weather-compensated control unit)

From this model's manual
Verified against the Viessmann Vitodens 050 W Bpjd 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

Locate the filling loop (a flexible silver hose) underneath your boiler or near your pipework.Gradually open the valves on the filling loop to allow water into the system.Monitor the pressure gauge on the front of the boiler until it reaches the green zone (typically between 1.0 and 1.5 bar).Close both valves firmly once the pressure is correct.

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