Fan Coil Unit Piping And Valves Connections
Fan Coil Unit Piping And Valves Connections
(OP)
Dear All,
I have am recently appointed as design engineer n an hvac firm,, I have an issue with an standard detail available here of fan coil units connections.
according to detail:
tow way motorized valve is sussed for by-pass on CHWR line and then double regulating valve(Balancing Valve) is also used
I want to understand here connection with each other,, either it is a good approach to have both in same line ? or this system can be enhanced in more better way??
I have am recently appointed as design engineer n an hvac firm,, I have an issue with an standard detail available here of fan coil units connections.
according to detail:
tow way motorized valve is sussed for by-pass on CHWR line and then double regulating valve(Balancing Valve) is also used
I want to understand here connection with each other,, either it is a good approach to have both in same line ? or this system can be enhanced in more better way??





RE: Fan Coil Unit Piping And Valves Connections
I don't understand your question and the language is not clear.
RE: Fan Coil Unit Piping And Valves Connections
RE: Fan Coil Unit Piping And Valves Connections
Please comment if i can improve this detail by changing valves
RE: Fan Coil Unit Piping And Valves Connections
knowledge is power
RE: Fan Coil Unit Piping And Valves Connections
You would want pressure taps at the coil to verify flow for those.
RE: Fan Coil Unit Piping And Valves Connections
Looky here:
http://www.kele.com/templates/content.aspx?id=4946
and here:
http://www.kele.com/templates/content.aspx?id=4942
and here:
http://www.kele.com/WorkArea/linkit.aspx?LinkIdent...
and here:
http://www.kele.com/WorkArea/linkit.aspx?LinkIdent...
Best to you,
Goober Dave
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RE: Fan Coil Unit Piping And Valves Connections
RE: Fan Coil Unit Piping And Valves Connections
cdxx139 yes it is a good practice, just want to improve it.
HerrKaLeun Thanks for a good suggestion.
DRWeig Sir, you have sent me good material i will study it and obviously it is better to reduce pressure drop on pump head by using it. I will try to make it better and will let you know. Thanks a-lot Sir.
SAK9 you approach is good n thanks.
RE: Fan Coil Unit Piping And Valves Connections
RE: Fan Coil Unit Piping And Valves Connections
and I'm assuming this is a fan coil and not a heat pump.
personally I wouldn't use the auto vents because they suck. leave the stop cock to manually bleed air or get rid of them all together and add another hose connection after the two way so I can flush out the coil in either direction or blow out air fast with a hose and bucket. the maintenance guys will love you.
I don't see any unions anywhere unless they are at the flex connectors.
RE: Fan Coil Unit Piping And Valves Connections
with on/off you also have more valve movement becasue of cycling.
and how do you maintain DAT if you have on/off? Depending chilled water tmep you may get 50 or 60°F or whater DAT if you have on/off.
DRWeig: I thought about your idea of not having balancing valves. your ideas, as ususally, are pretty good and well researched.
One thing I woudl be cocnered with woudl be rogue zones or failed valves that will steal all the water (or at least unnecessaarily increas pump speed and reduce dT).
But I think either going to the expense of PICV, or no balancing valves. All that balancing valves do is provide an opportunity for generatiosn of people to randomly play with them and they never are actually balanced anyway.
RE: Fan Coil Unit Piping And Valves Connections
if your Modulating the valve a balance valve is not really necessary and if its part of several off a main I would think you have a circuit setter valve for the loop.
I want to correct my last post. I would keep the gates just for isolation, but I like ball valves. I hate when I go to a job and the one and only valve leaks and I have to drain the line or system. cost a bit more but well worth the redundancy.
RE: Fan Coil Unit Piping And Valves Connections
you always want isolation valves, correct.
not sure hwy you differentiate between balancing valve and circuit-setter. afaik this is the same thing in what they do, just different names. I think traditionally in CV pump systems pump still had balancing valves, and the branch balancing valves ere called circuit setters. Obviously with Variable pumping only the branches need balancing.
RE: Fan Coil Unit Piping And Valves Connections
I just think we just do what is always done because its CYA. I cant tell you how many buildings I have been in where every balance valve, circuit setter, butterfly valves are wide open and they have no issues. I said to a building manager, this is amazing that an engineer figured out everything exactly so you don't have to use or need all these extra parts you paid for and installed.
So going back to the OP question, the drawing is fine. it will work. But Just give me two isolation valves, two drain hose connections and a properly sized modulating valve and a y strainer. and maybe gauge ports so I can read pressures maybe once a year. anyway, not really knowing what this coil will be used for, its just some ideas for value engineering.
I have been getting into more closed loop heat pump condensor loops using VFDs. So this subject in interesting to me. I'm not convinced the ROI is worth it, to change from a CV system. But I'm sure someone will show me the light.
RE: Fan Coil Unit Piping And Valves Connections