using ball valves with shraders for future multi zone expansion

mthmlf84

I have a multi zone lg system being installed in a converted barn and we are planning an extension to the barn where a split should also be installed, eventually. Since that’s not happening that soon but we want the system up and running ASAP, is it advisable to connect the liquid and suction lines we need to the branch distributor box that distributes refrigerant and current to the indoor units and terminate them with ball valves with shrader valves, with the shrader valves on the side of the future units so those can be properly evacuated and leak tested once it’s time to hook them up? 

See drawing for what I mean. 

the closed system with valves would be leak tested and evacuated as normal, commissioned, and eventually the new unit would be connected, refrigerant charge adjusted, etc.


edit: the square in the middle is the branch box. 3/4 suction 3/8 liquid in, 1/4 liquid 3/8 suctions out +comm wires

ratio

That's fine. I'd consider ball valves on the current heads too—no telling when you might need to take one out of service but don't want the whole system down.

I just went through this on a 30 head VRF system, where the engineer didn't spec 'em & the owner "couldn't afford" them. <sigh>

JUGHNE

I assume we are talking of ACR rated ball valves?

ratio

The OP mentioned valves with schraders, so I think so.

mthmlf84

yes i was thinking of getting the RLS ones-->

https://www.supplyhouse.com/RLS-RPBV038-3-8-ODM-Ball-Valve-w-Schrader-Valve

it just seems like a good idea to put one at everey unit even, right, but I don't know if they're known to leak over time or if there's certain brands to avoid.

It's a multi head system with something like 13 lbs of 410a in it, sure seems like a good insurance policy to add service valves in case something is wrong with one unit.

mattmia2

I would use a valve with a flare cap that goes over the ball stem when it is not being operated. I would also cap the open side of the ball valve until you are going to add the new zone.

ayetchvacker

I would braze capped stubs onto the AHU side of the valves as well just in case the valve fails or leaks slightly. If it does at least you’ll know by putting a gauge on the port with the valve closed. Great idea.