Motorised Valve

[CADmanJP]

Further to my recent problems with heating I now have a problem with my hot water.

The programmer is working (for the heating as well) and the boiler is firing up but I am not getting any hot water out of my taps (except a little bit of half hot water this morning). I am thinking that the motorised valve is broken.

If this is the case are there any tips on how to test for sure that it is not working and also how much it should cost for a new one and to have it fitted.

Any help or tips would be graefully appreciated.

 

[kevplumb]

there is usually a lever on the motor to put the valve mid position

ie heating and water

 

[CADmanJP]

Thanks for that.

At the moment I have it right over to one side. Last night I tried changing the position of the lever but it made no difference. Also I read that when you move the lever there should be some resistance, which there isn't.

I'll try it in the middle position when I get home.

Would any one mind explaining exactly how this valve works with the heating and water so that I can understand it a little better.

 

[stem]

Have a look at this link, its the best description I've come across of how the three port valve works.

www.diyfaq.org.uk/plumbing/plumbingpage2.html#midposition

 

[ChrisR]

The lever only opens the valve half way, ie to ch + hw.

If there's no resistance it's already there, or further, at ch only.

 

[MANDATE]

And the reason being if CH was called for when progammer switched it off it stays there because there is power to drive it or hold it at the end stop from the HW OFF wire.
Turn the programmer off for about 30 secs and spring will pull valve back to HW positon.