Vailant VCW 242EH, Sticking diverter valve?

Also had to make an adjustment to allow a minute gap (0.2mm) between push rod and the cam on the servo. The push rod was constantly making contact with the servo not allowing it to return to the proper position via a small spring. (done by lowering the screw on top of the rod )

godfrey65
January 2010

I was also getting the problem that the movement on my diverter valve was not sufficient enough to allow the actuator to make contact with the microswitch. First thought was the diaphram. (I ordered one from my local merchant and 3 wrong ones were sent). When I got the correct one and stripped out the diverter valve only to find the original one was in good condition. I stripped down the rest of the diverter valve and found a few barnacles of crap which I removed. I reassembled everything but the problem was still there.
Following the diagnostics listed in the boiler manual, I stripped all the control lines out and they were all clear.
The manual then says to check/replace the diverter valve. I bought one from ebay for £45, which was a reasonable trade off for what I would pay to have a boiler engineer in. This had the same problem.
My next port of call was the servo valve. Not enough water pressure was getting to the right chamber in the diverter valve to allow the actuator to make contact with the microswitch. Stripped it down, gave it a good clean and all running good now

godfrey65
December 2009