Air Conditioner - Inconsistent temperature

[art]

I have a attic/central air conditioner that is not sending cold air to one ceiling vent. I checked all of the vents with the thermometer and the temperature ranges from 62 F - 70 F. The temperature reads 80 at the problem vent. There is a strong flow of air out of this vent, as strong as the others. It is insulated in a similar way to the other pipes that service the vents, only it is just a couple of feet longer than the rest. I detect no air leakage.in the system. I opened up the "box" that all of the pipes connect to and although it is dirty in there, the air is 60 F and is flowing to all of the pipes. The inside air filter is new.

Why is one vent performing worse than the rest?

Thanks, Art

[Joseph Meehan]

Because it is picking up more heat somewhere along the line. This can happen if the air flow is slower (less total volume of air per cross area of the duct.

I suspect that in fact it is not as well insulated as it should be. In fact I suspect the others are not as well insulated as they should be as well.

[Dr. Hardcrab]

Could it be the return???

Just a thought....

[Art]

If you have flexible duct put in about a decade ago the stuff was not resistent to sunlight and fell apart in some houses or on some runs.

[m Ransley]

62-70 isnt very cold , when did you get a check up last. I dought duct insulation is proper.

[PJx]

You need to run new duct work.

The newer ductwork is better insulated and will fix the problem you mention.

Pj