I had my whole hvac system reinstalled last year by a contractor. He moved my evaporator to the attic and did the zoning (I have 4 zones). I have two problems that need some help guys:
1/Some months ago, when the weather was very hot and we used the AC, I noticed there was a lot of condensation under the supply plenum (and dripping on the wood). You can see in my picture, the evaporator Rheem is on the right side and next to it on the left is the supply plenum. I called him and he said that is because there is too much cold air inside when we turn on only one zone. Is that true? Should I buy the duct insulation at Home Depot and wrap it up?
2/ In my other picture, you can see the draining pipe on the right, one bare copper tubing next to it and a wrapped copper tubing on the left (I believe one for hot and one for cold). All coming into the plenum. Last time I checked, the tape (is it butyl? I am not sure) wrapping around the cold copper tubing and the draining pipe came off. Lots of air leaks through as you can see. So the contractor came and took the old black tape off, put new one in, wrap around the new tape with some foam insulation and zip tie them.
Today I checked again, the same thing happened to the hot copper tubing. The butyl taping coming right off the seal deal to massive air flow. My question is what is the right way to seal off those holes on the plenum? Last time when the contractor did with new taping and foam insulation, the holes were kind of tight but not completely since I can still hear the noise of air going through, although not as much as before.
Really thanks for your help and wish you guys a happy holiday