how can i fix my vaillant turbomax vuw242e combi i cant get hot water and the 3way valve was replaced 18 months ago

barry beazant, March 2011

I take it the boiler has a black front and green dials. The microswitch will not be making properly on the diverter to fire up the boiler. If you unhook the top cover open up the lower door and undo the one screw on the left hand side the black cover wiil drop down. Look on the right hand side of the pump and at the back connected to a big brass bit is the dhw microswitch. There is a little phillips screw just above the microswitch which when loosened you will be able to move the position of the microswitch and turn switch in a clockwise direction to get it closer to the white plastic arm which comes down when the hot tap is turned on

gazdaz36, March 2011

Not sure the model, I would have to look it up. But have you heating? If yes, well boiler in general is ok, If you had 3 way replaced 18 months ago, would not expect it to go again, UNLESS, a lot of corrosion in your system. Listen for the valve moving. Maybe take front off, the 3 way has an electrical section, and a mechanical section, It is possible to take the electrical part off from the mechanical. usually a 1/4 turn, but you may need to press on some part slightly, just look. You would possibly then be able to see the electrical part moving, when hot water is called for. If it turns, Valve could be stuck or not working, depends on type, if you can turn the valve by hand, NOT while the system is on. If very stiff, valve. Try using some anti corrosive additive, You would need to flush it through first. both available DIY. Might clear and blockage, otherwise new 3 way again. But get it flushed and an anti corrosive added.

Sheepdog, March 2011