UFH - Two port valve on flow or return?

[SpecialK]

Hi,
I'm plumbing in my UFH and will be putting a two port valve in so I can control the UFH and radiators separately.
Is it OK to have the two port valve on the return from the radiators rather than the flow?
Should I install a two port valve on the UFH and radiators? Or just one on the radiators so I can run the UFH independently.
Thanks

 

[flameport]

Flow is more usual, although it will still work with the valves on the return.
You need a valve for each part of the system, so one for the radiators and another one for the UFH. A third valve for a hot water cylinder if there is one.

 

[SpecialK]

That's great thanks.
The return is much easier to get to so will probably put them there.
Do I need a bypass as when both valves are shut no water will flow? It's a vaillant 831 combi. Not sure if it has one internally!

Flow is more usual, although it will still work with the valves on the return.
You need a valve for each part of the system, so one for the radiators and another one for the UFH. A third valve for a hot water cylinder if there is one.

 

[ianmcd]

If you put them on the return they will possibly make a loud clunk when they close, if another circuit is still running, put them on the flow as they were designed for