Wirsbo ADS Software

DanHolohan

you may be confused by the meaning of Cv. Cv is the flow rate across a valve that causes a 1 psi drop in pressure. In this case, 3.5 GPM will give you a 1 psi drop (or 2.31 feet of head) across the valve. You can flow 5 GPM but the pressure drop will be 2 psi (4.62 feet of head) instead of 1 psi. Hope that helps.

Andy Morgan_2

3 way valves and Wirsbo ADS

I just started using the new ADS software from Wirsbo. Much better than the old one. Here is my problem: I designed a job with 5 small zones. I wanted very simple control strategies, so the softwafe combined them into 3 temperatures with 3 thermostatic mixing valves. Piping would be set as follows, coming of a primary loop: mix valve, circ, split piping to 2 manifolds, back through two zone valves,combine into one pipe back into primary loop.
Other two temps would be similar. The total flow rate for each temp is about 5gpm, 2.5gpm for each manifold. The mixing valve that the ADS program spec'd is only rated for 3.5 cv. What in the heck did I miss? How do I get 5gpm thru a valve rated for 3.5?

Please help, I am now totally confused!

Andy Morgan

R. Morgan Mechanical, LLC

Andy Morgan_2

So then

the circ must be able to overcome this plus the ft of head for each zone, or just the highest number between the two?

What I missed was where the 1 psi across the valve comes into play.

Andy

DanHolohan

Just the pressure drop

around the highest-pressure drop circuit, Andy.