Central air - problems cooling

[danmc68]

I bought a Rheem 3.5 ton unit about a year ago for my 1880 sq. ft. house. Today it is 90 degrees outside and I can't get it below 73 in the house. The AC has been running continuously for about 8 hours. I've got it set to reach 72, but it can't get there. My old unit (~25 years old) that was replaced could cool the house to the mid 60's pretty quickly. The new unit seems a lot less powerful. Does anyone know if this is normal for the newer units, or does it sound like I've got a problem?

Thanks, Dan

[Stormin Mormon]

Where are you, and what's the humidity like? That's the factor few people consider. Humidity will really load down a system. Other factor. Do you have a vestible or airlock? I've been to one house where the system wasn't cooling. They were both smokers, and opened the door for many seconds each time they stepped out to smoke.

If the problem continues, I'd call a repair company. Of course, they will be rather busy now. By the time someone comes out, the weather will be cooler, and you can guess the rest.

[Steve]

In this neck of the woods, an average house that size is only gonna need 3 tons. Long run times with a smaller, correctly installed system will freeze your ass out at the 75F @ 50%RH I design for. You need to get somebody that knows what they're doing to come check out the system. FWIW, if you got the house down to the mid 60s, you were running an evap SST bordering on freezing. I would also be willing to bet that you had to turn it down that low because it had been grossly over charged. Your installer is an idiot.

[The Daring Dufas]

Would you guess his old system had an expansion valve instead of a cap tube or piston? I was in Johnstone the other day looking for a TXV for a problem system that happened to be a Goodman. The counter guy pulled a Goodman part numbered valve kit made by Sporlan that fit in place of the metering piston on the Goodman evaporator. The only brazing needed is to pick one of several T adapters from the kit to install on the suction line on the evaporator. The T adapter has a 1/4 fitting for the external equalizer tube from the TXV. The kit even includes a foam rubber cozy to insulate the expansion valve. When me and the salesman went through the kit and saw how versatile it was, I exclaimed "COOL!" (no pun). There is a lot of stuff at the supply house that nobody knows about unless you sit down and read their catalog like, um, every time you visit the odoriferous reading room.

TDD

[HVAC]

Call whoever put it in.

Have them check it.

[Grumpy]

I am not AC person but you are running at border line so if your house have any leaks you are lucky getting to 73

[larryp7639]

-------------------------------------

Thanks you for the post.

[larryp7639]

-------------------------------------

Thanks you for the post.

[Sure,Not]

How big was your old unit? 72 is cold.

[Sure,Not]

Not very green are you? 73 is damn cold.

[Stormin Mormon]

Sounds like either you have major humidity, air flow problems, heat coming in, or a system that's way below capacity.

[Alexander]

We get paid to make it as hot or cold as the customer wants and can afford. Al Gore is busy getting his ass handed to him in a divorce case and is too busy to haunt you if your comfort zone is beyond his hypocritical standards. You are aware that his so-called green home eats enough energy to power a small city.

>

[The Daring Dufas]

Al Gore's electricity bill:

TDD