actually close (not just isolate) loop on a TruFLOW Jr. manifolds

think I might have a leak in one loop/circuit off my uponor/wirsbo manifold. I would like to close off this loop but keep running hot water through the remaining loops. This way, I can keep heat on while testing and repair. If leaking, it'll take me a while to move furniture & flooring to make repair.

I have isolation valves on the supply manifold and balancing valves on the return manifold. I see (on pages 3 & 4 of this doc) how to close the isolation valve on the supply manifold, with the allen key that came with the assembly. What I'm not seeing is a way to close the balancing valve--I'm afraid water from other loops coming back into the return manifold will feed my potentially leaky loop from the supply end.

Is this possible, or do I just need to drain the system, disconnect and cap off the questionable loop?

Thanks for any information!

 

Do you still have the isolation valve plastic cap on the manifold?(part#15 on the replacement parts page) If so all you need to do is shut the valve by turning the cap clockwise.

 

Great. I definitely do have that cap on the return manifold. I assumed it was just a protective housing that didn't really do anything in terms of the valve. I had unscrewed the top half of the cap to see if there was any (metal) bits to mess with, but couldn't quite see past the lower part of that cap assembly.

I think I'm realizing that this balancing valve kind of gets pushed up by returning flow, but only as far as that cap lets the needle bit move upward. So by tightening that cap, it pushes the valve down to the closed position. Neat.

So if I have it right, once that's done and the supply valve is also closed off and I open that circuit, a bit of water might gush at first from any pressure w/in the loop, but it won't be like the whole system coming at me. After that, I can push out the water with my air compressor, and run an air pressure test. Does that sound right?

Thanks very much!

 

That is actually the isolation valve, the balancing part is where the Allan key goes...read the doc that you linked to..the isolation valve is held open by an internal spring. You have it correct as far as the water.