TECHNICAL

Caravan & motorhome technical questions

Question

HOW TO CHANGE WATER DIAPHRAGM ON VAILLANT WATER HEATER

Answer

Disconnect the water supply pipe and the pipe that goes to the heat exchanger. At the top of the water control assembly which contains the diaphragm you will see two horizontal screws and by loosening these the assembly will be freed. Lower the assembly carefully and four screws will separate the water control assembly allowing you to replace the diaphragm. If your heater has suffered frost damage you will probably need the replace the upper body as well in order to repair, our part 117057.
Replace the water control assembly making sure not to overtighten the horizontal screws.