·Future Nine Corp..
When near 0F my HVAC registers drop 20F on their run
My new HVAC system seems to lose heat during a longish run on one leg. The run is in my attic which is not insulated above the ceiling. I believe R8 is used as insulation for the ducts. The hottest duct going to the coolest duct show nearly a 20F drop in heat from the start of the run until the end when it's very cold outside.
Is this unusually high? The warmest is about 88F at 0F, and goes down to 70F on the coolest duct along the run. The other heat pump run, seems to drop only 6F from warmest to coolest, but it's a shorter run. Each of these runs is in the attic, which isn't insulated.
They are tied to a lower level, and heat that as well. In the better insulated lower level, there seems no measurable disparity between ducts. Overall, the lower level is easier to heat.
The long run, has a lot of drops (50% more than any other run 18 vs 12 for the other shorter attic run) as a result air movement also seems to be slow, particularly for the last few drops. Could this be an insulation, air movement, or combination of the above issue? Is there a way for me as a homeowner to determine this, or do I need a professional?
Congress could mess up a one piece jigsaw puzzle.
TexDave's not herePremium
It's hard to tell from here, even with the information you've given. If it's new and you're not satisfied, call back the contractor who installed it. Maybe they can figure out if there are any issues.