How to Fix / Troubleshooting

Safety first: Disconnect power before removing the valve head cover.

Remove cover: Take off the plastic cover over the valve head to expose the motor and gears.
Inspect gears: Look for worn, missing, or damaged teeth on the plastic gears. Check for debris lodged between gears.
Check cam alignment: Ensure the cam is properly seated on the shaft and not wobbling.
Lubrication: If recommended by Viessmann, apply a small amount of approved lubricant to the gears. Do not use unapproved greases.
Replace motor/gear assembly: If grinding persists or gears are damaged, replace the Viessmann valve motor and gear assembly.

Softener makes grinding or clicking noises from the valve head during operation

Possible Causes