anti-gravity valves?

[stevewilliams]

I've recently installed a DIY solar hot water system but am having a problem with losing heat from the hot water cylinder which is reverse- circulating up the primary boiler (28mm) flow pipe. This is a gravity system and I am wondering whether there is such a thing as an anti-gravity valve which would allow the water to flow in one direction only although I can't imagine how this would work?

I think my alternative is to update my system and install a motorised valve controlled by a cylinder stat which would presumably close off any gravity flow when closed?

Your comments are gratefully received and if anybody is interested in my solar DIY installation (cheap and highly recomended) - please ask.

Cheers

Steve

 

[ChrisR]

Yes - called swing check valves and they work by gravity.

eg http://www.bes.ltd.uk/products/graphics/7518.gif
bes item no 7463 is 1" and £2.26+.

Alternatively perhaps, there are temp operated valves which need no lectric, like cyltrol valves.

 

[stevewilliams]

Thanks for that

Presumably they are seated in position under gravity and are forced open merely by the push of the rising hot water? What are they made of?

Cheers

Steve Williams