Flow of water problems...

[AMontemagni]

I have 2 zones for my baseboard heating system. I have attached diagram of the system.

My problem is that whenever I have Zone 2 turned on, it will also heat Zone 1 and vice versa. So obviously I need to install a flo-check valve somewhere, but I don't know where.

Can someone tell me where it should be installed?

I can supply pictures of the system, if necessary.

[HayZee518]

Put one in each line AFTER the zone valve. Make sure the arrow points away from the boiler (zone valve) The return for both lines is manifolded together into one common return path but with one zone operating the flow valve there'll be enough back pressure to keep the other valve closed. When both zones are open both flow valves will open.

[AMontemagni]

I am not sure where you are saying to put it. I have a valve on each zone at each end of the system. If we are looking at my sketch, should it be on the right hand side after the valve with the arrow pointing away from the boiler? Or the valves on left side of the sketch with the arrow pointing towards the boiler?

Also, one thing I didnt mention was the flow of water now. The arrow on the pumps are pointing towards the boiler.

Thanks

[HayZee518]

Depending on the pump's location the arrows will be pointing either away from the boiler or towards it. The diagram I drew up shows the check valves AFTER the taco zone valves with the arrows pointing away from the boiler in direction of water flow.

[AMontemagni]

That's for all of your work....
The pumps are pointing towards the boiler; so I would assume that is the flow of the water, which would be the opposite of your sketch. Is it okay that I install the flo-check valves with the arrow pointing towards the boiler.

Also, I purchased a horizontal flo-check valve (Taco), but due to the pipes where the pump is, the check value would be 6-8 feet from the pump to get it on a horizontal run...is that okay that it is that far away?

I know very little about plumbing and HVAC, however, I am very capable of sweating any joints.

[HayZee518]

If your taco valves are mounted on a vertical riser then get two vertical check valves. If they are on a horizontal run get two horizontal check valves. (One for each line) Was just thinking about it - how about if one of the zone valve seats were leaking? When one opened the other could be leaking past. Usually the return spring is heavy enough to close the valve but if the seat is worn - it would leak.

[KSever]

Question Hayzee,
Why wouldn't you install them check valves at the end of each zone?



Installing them at the end of each run prevent feedback to each line.

Wouldn't installing them behind each zone valve allow hot water to feedback all the way to this check valve and also heating up this entire zone.


I presently have two boilers for two zones in my house but am going to change this over to one boiler and two zones.

[HayZee518]

You could mount them at the end BEFORE the isolation valves and manifold. Think of it - it makes more sense. Just make sure those arrows point in the correct direction!