How do I change a diverter valve on a Vaillant 242e Turbomax?

I have changed the pressure differential valve and micro switch on my Vaillant 242e turbomax but hot water still not working. Central heating is fine and the pressure valve is now operating. I am assuming the diverter valve is broken. DIYer. Any help gratefully appreciated.
Bizanium, August 2006


done
Vaillant combi
i have put in a roomstate to the boiler and used the wrong connections put it in to 4 and 5 instead of 3 and 4 and blown one of the 3 fuses on the boiler i have replaced the fuse but the hot water and heating will not work what have i blown up please

phillip watt, December 2006
Hi, unscrew the motorised head of the diverter valve first and turn the boiler on and off a couple of times to make sure the centre plunger is going in and out. It should do this on power on.

Paul, September 2006
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