Gymnasium Duct Insulation Recommendation?????
Gymnasium Duct Insulation Recommendation?????
(OP)
I am requesting some assistance/direction in the design of an air-conditioned gymnasium. The system (DX rooftop) will provide cooling during occupied hours for the summer months. My concern is that there may be a condensation problem on the uninsulated ductwork currently designed. The lead engineer has noted that insulating duct in this space in "not typical". However, it is probable that the space dew point will be higher than the duct temperature and cause condensation. Can someone indicate if the insulation is typical and possibly a resource to reference? Thank you. Brian
The facility is in the Metro NYC area.
The facility is in the Metro NYC area.





RE: Gymnasium Duct Insulation Recommendation?????
My $.02 worth.
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
In the arena you identified, did you have condensation problems?
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
The RTU has a preheat and DX coil. Has anyone every seen a the coils reversed? If these coils are reversed, this could provide the reheat to the space (as required).
RE: Gymnasium Duct Insulation Recommendation?????
I would reccomend any piping going through the roof space to the RTU be covered in Armaflex and penetrations foam sealed BEFORE insulating. As for the duct work, the main trunks connecting directly to the RTU should be insulated, the branches are okay. And you only need to insulate about the first 12' or so of the duct.
As for your last post, yes I have seen this reversed. Sometimes it has worked and sometimes it caused the cooling coil to be frozen and break. If you need re-heat, it might be more economical to add reheat coils throughout the building.
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
I do have a question regarding the recommended insulation length - 12'. Will the remainder of the duct surface main (about 50') be greater than the space dew point temperature. I figured the insulation would maintain the metal duct temperature further downsteam.
I am also going to look into the hot-gas reheat. This seems like a good idea. My initial thought was that the climate in NYC would not cause freezing concerns on the DX coil. However, I will take a look at other options.
Thanks again.
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
I would also insulate the entire length. When this is started up after sitting for a long time, hot and humid, I think there is a real potential to have condensation anywhere the duct is cool.
RE: Gymnasium Duct Insulation Recommendation?????
RE: Gymnasium Duct Insulation Recommendation?????
i wouldn't be concerned about it
RE: Gymnasium Duct Insulation Recommendation?????
I think it all depends on the attachment method. Simple fastners seem not to work for prolonged running times. The resin method seems to hold the best.