Air Conditioning - Desperate need of AC advice

I have an 1800 sq. foot house with a 3.5 ton, 4 year old piece of crap Tempstar unit. It has never been great, but it has kept us comfortable enough. I have had it checked because it runs from 8am until 11pm in the summer, and the guy basically told me I got what I paid for...it is doing what it is supposed to do. Hurting things is the fact that I have high ceilings in four rooms.

Yesterday I came home and it was 81 degrees in the house, with the AC blowing full bore. I just had a serviceman out last month, he checked it out and gave the coil an acid bath.

The air coming out of the vents seems cool, but it is not blowing hard. I let it run all night, and the house only got down to 74 degrees. I cut if off this morning for 6 hours, in case the coil was frozen. I just went home and checked it in the daylight, and it was not frozen. I started it up and found more of the same. I am facing a hot holiday weekend. I can't get the warranty guy to call me back, with this being the Friday before a Holiday.

Any ideas on anything else I should check?

Thanks so much for any help.

-Hot in Tennessee

wmmiller

I doubt that I can provide you any immediate help but perhaps can get you on the right track.

It does seem on the surface that the size of your unit should be enough capacity to more than adequately cool your home.

two areas that I would look at.

1.Is the big copper line at your condensor cold and wet? small line should be warm.
2.take a measurement of the supply temperature at several of your vent/registers. It should be in the low 60s minimum-no higher.
(You can get an inexpensive digital thermometer at HD or Lowes)
3.What kind of air cleaner cabinet(if any) do you have?
4.has unit ever cooled your home satisfactorily?
5.have you taken a look at your ductwork for any obvious leakages?
6.is air flow at supply vents strong?
7.No signs of frozen lines at condensor or coil?

Sorry for your trouble. I know it's hot as I live in the South.
Post back when you can.

Well, I got lucky and a buddy at work has AC experience. He came over after work and found out that the evaporator coil was frozen solid. I had a guy from a local AC repair shop out just last month, and he only checked the condensor coil.

The problem turned out to be a mass of junk sticking to the coil. (Dust, pet hair, etc.)

We cleaned it with a foaming solution, thawed it out, topped off the freon, and it runs better than ever. I also bought a better quality filter for the return (so that it won't give way on a corner and let junk get past it.)

Thanks for your suggestions, Tigerdunes.

I sure hope you bought your buddy a beer. Good job.