Why is my central air inefficient ?

[ovi8]

if it's an insulation issue, you'd have huge heat loss during the winter too.

If it's not blowing cold air at the vent, say about 59F, then that's the first thing I'd address.

[accufitgolf]

My experience with central air not cooling enough was lack of freon in the system, but that leads to where did it go and a whole other ball of wax.

[James1202]

Originally Posted by K'ledgeBldr

I just love how everyone assumes it has to be the A/C.
Granted, the system should be checked- first and foremost.
But, let's assume it's working properly and it was sized properly for the house. Half the country is experiencing record high temperatures, so a lot of systems are being overworked. They are working at their full effiecency.

So, what's the problem?
Insulation! And I'm not talking about just the attic (although that's the prime suspect); but everywhere. Walls, windows, doors, etc.
Then there's the attic ventilation- or lack there of! That heat can just radiate right through the ceiling.

Also, insulation of the ductwork. Often times the air is cold when it leaves the AC blower but gets heated as it travels through the attic portion of the ductwork.

[NM posts]

All of my ductwork is in the crawlspace but I'm betting it gets pretty steamy under there...I decided it has to be insulation because the AC cools very well late at night. Fortunately, I'm about to start shopping for a house...I can live with my cheap yet hot/humid rental for a couple of more months... thanks all