****** HVAC duct in an attic...
- Thread starter danski0224
- Start date
Pretty common to see attic duct work falling apart after a few years.
I helped a friend run duct in his attic. He fought me on using the pudding type duct sealer and wanted to just use tape. I told him in ten years all that tape will be falling off the duct and the system will be full of holes, "is that what you want?" He didn't fight me after that.
There was a retail store we regularly serviced. One hot summer day they called because the store was warm. I looked over the RTU and it was running wide open all 25 tons yet it was warm on the store. I checked return air temp and it was a lot cooler than the store's temperature. I popped my head above the suspended ceiling and there was a section of 3' x 3' fiberglass duct that had fallen apart. I was able to repair that section, but looking around there were seams in the duct all over that were split open. The store owner fought me on doing repairs! I couldn't convince him the RTU would cool the store more efficiently if the duct was repaired. I finally told him that is was his money and left.
I helped a friend run duct in his attic. He fought me on using the pudding type duct sealer and wanted to just use tape. I told him in ten years all that tape will be falling off the duct and the system will be full of holes, "is that what you want?" He didn't fight me after that.
There was a retail store we regularly serviced. One hot summer day they called because the store was warm. I looked over the RTU and it was running wide open all 25 tons yet it was warm on the store. I checked return air temp and it was a lot cooler than the store's temperature. I popped my head above the suspended ceiling and there was a section of 3' x 3' fiberglass duct that had fallen apart. I was able to repair that section, but looking around there were seams in the duct all over that were split open. The store owner fought me on doing repairs! I couldn't convince him the RTU would cool the store more efficiently if the duct was repaired. I finally told him that is was his money and left.
bwringer
Well-known member
Sympathies.
When we got a new heat pump, it wasn't quite performing up to snuff so the HVAC company sent their Ninja. They actually called him that. A tiny dude who barely spoke English, and was their mystical wizard troubleshooter. Anyway, he crawled here, there, and everywhere for an hour with temperature and air speed probes, and finally found much the same situation, except worse, on a 10" return duct, in a place no one had spotted since the house was built.
Some lazy-*** builder long ago hadn't bothered to actually, you know, attach the duct to the plenum. Literally punched about half a jagged hole using a hammer and sort of put the duct nearby, and went back to his beer cooler and forgot all about it.
Anyway, it was simple enough to correct (it was in a spot even I could reach), but vastly irritating to think of 35 years of wasted energy.
When we got a new heat pump, it wasn't quite performing up to snuff so the HVAC company sent their Ninja. They actually called him that. A tiny dude who barely spoke English, and was their mystical wizard troubleshooter. Anyway, he crawled here, there, and everywhere for an hour with temperature and air speed probes, and finally found much the same situation, except worse, on a 10" return duct, in a place no one had spotted since the house was built.
Some lazy-*** builder long ago hadn't bothered to actually, you know, attach the duct to the plenum. Literally punched about half a jagged hole using a hammer and sort of put the duct nearby, and went back to his beer cooler and forgot all about it.
Anyway, it was simple enough to correct (it was in a spot even I could reach), but vastly irritating to think of 35 years of wasted energy.
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danski0224
Well-known member
OccupantRJ
Well-known member
My shop has a package heat pump system. When I ran the duct I used round galvanized metal, seam sealed with mastic sealer, wrapped with 2” foil faced insulation and used UL approved tape, then strapped it with nylon 300 lb straps at regular intervals. I did not want to have to worry about duct failures and having to deal with them in an enclosed hot attic after ceiling was installed. The straps were free from opening imported cartons at work, so why not use them.
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danski0224
Well-known member
Um.....