Normal cooling loss?

[Robby9]

My TT is 32' long. At the end of a duct that is about 15' long the air coming out of the duct is 10 degrees warmer than the air coming directly out of the AC. Is this normal or is it indicative of a duct problem?

[Robby9]

The duct was poorly taped to the AC plenum and there were gaps/tears in the tape. After re-taping the duct temperature loss was reduced to 2 degrees. (Today was a cooler day, so that may have helped somewaht too)

[Robby9]

The ducting I've seen is a lined styrofaom type substance, so it should provide some insulation. I wouldn't have been suprised to see a slight temp rise, but ten degrees seems excessive. It got me wondering whether I've got a hole. Or a tear. In the duct works.

[aruba5er]

they don't us insulated ducting nor is there much insulation in the ceiling. sounds like a normal heat gain to me. I know in my camper there are areas where there is NO insulation. and what is used is about 1 1/2 thick. Probably R 4. Can't spend too much money on foolish things like dual windows or insulation. PROFIT job # 1

[fla-gypsy]

A 10 degree rise over 15' sounds excessive to me. You should check the connections of the ductwork. You bring up an interesting question though. I have never measured mine and now my interest is peaked.

[sch911]

Sounds normal. There is always going to be heat pickup in a long ceiling duct.