Why doesn't the whirlpool tub operate after draining the water and refilling it?
To clean the system, switch the pump alternately to high/low speed at least six to seven times.
The wet area of the pump has a vent valve. Open the valve until all the air has escaped and water starts to drip out. Alternatively, undo the connection at the pump and let air escape until you can see water. Do not try to do this whilst the whirlpool pump is running. If this does not solve the problem, contact your authorised Villeroy & Boch specialist dealer, who will gladly help you - HERE.