Zone valve location

[Mustang51js]

I am adding two zones to a single zone set up that I have right now, my question is about the location I install the zone valve. Do they go above the circulator pump or on the return side back into boiler.

 

[LS6 Tommy]

Where is the one you have now? Most want to put them on the return, but they should all be on the same side of the circuit...

Tommy

 

[Mustang51js]

I don't have any right now, I have one zone on the first floor, but I just put a second floor on and going to add two more zones. Just wasn't sure what side of the loop they go on if it matters

 

[Jim Sperry]

I've always seen zone valves on the supply side.

 

[The Cobbler]

zone valves that I've seen are on the supply side. but, are you adding zones to the single zone system to independently control the heat? do you have 1 pipe or 2 pipe system? you might need additional bypass line & or monoflo tees

 

[Liquidplumber]

It does not matter. Water is either flowing through the loop or it's not. They are more common on the supply side but it does not matter.

 

[anthony666]

they go on the return side

 

[anthony666]

bummer .. i was hoping for a discussion/debate .. now i'm gonna have to be 'that guy', sorry

zone valves ALWAYS go on the return side .. yes, flow is flow and you can put them anywhere and they will stop flow .. so why must they got in the return ??

the answer is pretty obvious; HEAT .. it's cooler on the return side.. there's basically two types of actuator, thermal & electric solenoid .. thermal get a heat demand and then melt a wax pellet which allows the valve to open, if we put it on the hot side the heat can prematurely open the valve when we want it closed .. electric solenoid creates a ton of heat when it operates, the fluid in the system cools the solenoid extending it's life