Using a diverter valve to connect 2 seperate C/H systems

[CrazyDave]

Hi I am looking to use a W plan divertor valve to connect 2 C/H systems but it would mean operating in reverse to the design. It would control flow coming in either end in the opposite direction to design. A simple stat would operate the valve. Is this the best way to do it or should I use two motorized valves.

 

[bobbo85]

I recently done a job on a church which had 15 rads and keston 55 boiler. I was asked by the architect to have the hall and the foyer and toilets kept so they could have them on seperatley if needed. I was given his method which was mindboggling he wanted valves here then there a return from there, madness ,so i just fitted 2 2 port mzv in the loft space and with it just meaning i only had to run a flow right back to the boiler it was easy.I stuck 2 clocks on and away it went .He told me when id finished "works like a dream,what was your idea 2 mzv (ha ha) never have been able to get the heat around",dont ask me what he was on about ,but just shows how some look at us like lower class men

 

[chrishutt]

Hi I am looking to use a W plan divertor valve to connect 2 C/H systems ....

Firstly the diverter valve would only be open to one or the other heating circuit, not both together. Is that what you want?

Secondly the diverter valve may be a design which closes off a branch by pushing a rubber ball against the opening. If the flow was in the opposite direction it may be that the ball would not press against the opening hard enough to prevent some flow seeping through.

Thirdly the sudden shutting off of flow may create a shock wave (like water hammer). The diverter valve would have to be suitable for reverse flow with very slow closing action.