Vaillant
Control Head / Tank O-Ring Leak
Softener leaks water from around the control head or top of the resin cylinder
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Perished tank O-ring, Cracked control head housing, Over-tightened or cross-threaded tank neck, Freeze damage
How to Fix / Troubleshooting
Safety: Isolate water supply and relieve pressure before loosening the control head. Disconnect power.
Steps:
- Dry and inspect: Wipe the area dry and observe where water reappears to pinpoint the leak source.
- Check tank connection: Gently loosen the control head from the resin tank. Inspect the large O‑ring for flattening, cracks, or cuts. Replace with a new Vaillant‑specified O‑ring.
- Inspect tank neck and head: Look for hairline cracks in the plastic. If the tank or head is cracked, replacement is required; do not attempt to glue pressure‑bearing components.
- Reassemble: Lubricate the new O‑ring with silicone grease, refit the head, and tighten evenly by hand to the specified torque.
Advertisements
Repair Difficulty
Hard
4/5
Required Part
Resin Tank O-Ring / Control Head
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements