PLEASE!!! 3rd 4th and 5th opinions needed

[bobcarter]

BACKGROUND:I'll try to make a long story short. For the last couple of years I have been locked into a "home warranty" that has been "repairing" my upstairs a/c unit....quite unsucessfully. The old unit, which was a 1.5 ton Goodman always cooled well, but leaked out freon in about 60-90 days. After many many times of just charging it up, the warranty company finally paid to have the evap coil replaced last fall. It worked through the fall but this summer was empty of freon again. They replaced the outside unit with a new Payne 1.5 ton 13 seer unit this April.

PROBLEM: On a warm humid day (Alabama heat 90-95* and high humidity) the system cannot meet the cooling demand. My upstairs is set on 77 or 76 and by 4:00pm it is usually 81 or 82 inside. I called the HVAC company and they said call the warranty company. They want me to pay more money and I'm getting the run around. My other unit that controls two floors works just fine regardless of temp or humidity.

Now for the question: I have a friend who is a building maintenace tech at our church come out and check the pressures. He said they are perfect, but the unit is only cooling 5 degrees from return to register. There is no condensation on the low side line outside. What would cause good pressures but no cooling???? My friend thinks it may just be undersidzed...but the old unit was the same tonage?Please help. I'm supposed to have someone come out in a coupe of days...but I just can't trust them.

[HayZee518]

low side about 60 psi, high side about 250

[bobcarter]

Low side was about 67psi and high side was high 100's...like maybe 185-195. I dont really remember. Supposedly someone is coming out this afternoon to look at it. We shall see.

[bobcarter]

I got some more information. Apparently late last year when they replaced my evap coil they went from a 1.5 to a 2 ton coil. So now I am wondering if that is why my new 1.5 ton compressor unit wont cool. My buddy that came out yesterday thinks that is probably why the discharge pressures are low and that the little unit is doing all it can.

[HayZee518]

yeah seems like that. the compressor is not matched to the evaporator. I see a new compressor in line

[HandymanTrainer]

I was about to say...the indoor coil was replaced first, then a new 13 seer condenser...and ne'er the twain shall meet. Now you say it was tow ton coil too? You may be able to solve the problem inexpensively by replaceing the orifice, but you are all guess work attempting to size the orifice correctly to bring the pressures into correct balance. And either way you are losing the benefits of the 13 seer unit you purchased. I would attempt to argue with the coil installer and try to guilt them into putting in the correct 1.5 ton 13 seer coil...(*note this is an apartment size unit at 1.5 ton and if your installer had trouble finding the 1.5 coil they can try apartment parts houses)

HandymanTrainer