[Bryanw92]

I live in Florida, where your A/C is a matter of life and death, and I will only buy Trane.

3500+ sq ft??? Are you the governor of Colorado? :-)

[Kirkwood]

What exactly do you mean by a freeze-up? And how did you determine that?

[Hoosier-Daddy]

Make sure the registers are NOT wide open.

[backinthefold]

Hubby and I own a HVAC company, but Chattanooga is a little far for us to make a service call :/

Hubby says the inside coil needs to be cleaned, its in a closet or the attic, you need to open the unit and clean them. A slant coil is easy to see / an A frame will have a panel you have to remove to clean. A HVAC parts house like CC Dickson should sell you a bottle of Green coil cleaner. Put some in a pump up sprayer and clean it up. If this still has the lines freezing up, call a service company to check freon levels, and MAKE them leak detect or add a stop leak sealant to the line set... Some service companies make lots of money ripping homeowners off not fixing leaks

The tonnage is is hidden in the model number, its 2 1/2 tons . This unit would work for about half your house. The unit is terribly undersized for 3,500 sq ft. This would not cool your whole home even working at top performance

I will answer anyones AC questions...

[ArmstedFragg]

Checked the coolant pressure? Mine used to freeze up when the freon got low.

[backinthefold]

One last thing...

~~So, what’s the best AC unit out there? Trane, Carrier, Lennox or ??~~

Overrated... we install Nordyne equipment, made in America, 10 year warranty, and good quality equipment

[Psycho_Runner]

There are a couple reasons why the line set freezes up. If there is not enough air flow through the coils, the line set will freeze. Check your air return to make there are no blockage.

The other problem is a faulty TXV valve.

Thats all i know. I am on the commercial side so my advice might be skewed.

[virginia lurker]

24AB300 This does not look like the entire model number for a Carrier. If it is a 2.5 ton it is too small for the house. It was most likely sized for the house before you finished the basement. Close the basement ducts and only try to cool the main living area. Do not use one of the pleated filters as they are too thick and restrict air flow. Use the cheap old fashion filter and change it more often.

[Billthedrill]

Thanks for the thread! I have a TRANE and it too shows some freeze-up occasionally. It's a bit over-engineered for my little place in northern Idaho and isn't often needed - we had our first warm day of the year today at a blistering 85 Fahrenheit and a lot of us were checking the aircon for the first time in awhile.

I did discover a secret to running the auto air conditioner efficiently when I was ten miles down the road and sweating.

It has to be turned on.

BTT

[ATOMIC_PUNK]

did a cross check closest i could come was

24ABB3 Comfort™ 13

Air Conditioner
with Puron® Refrigerant
1.5 to 5 Nominal tons

Carrier Comfort™ 13 Air Conditioner with Puron Refrigerant, Model 24ABB3, is available in 1.5-5 ton nominal-sized units.

Standard Features

Energy Efficiency
13 SEER / 11 EER
Sound
Sound as low as 74 dBA with accessory sound blanket
Reliability, Quality and Durability
Scroll Compressor
Field-installed Filter Drier
Front-seating Service Valves
Internal Pressure-Relief Valve
Internal thermal overload
Baked-on powder paint
Dense wire coil guard—Standard

Natural for them to freeze up in high use situations thats why they cover them with insulation but it could mean also you have a vacuum leak and are pulling moist air into the system if sot the compressor will freeze up and it wont work at all if it ws built in the 70 or 80 id get a new one replace the whole system i like carrier but i like trane better they see\m to last longer and have a heavier duty on off cycle

was the house built onto since this unit was installed ? if so it might be overworked !

[Marcella]

I live in Texas hot weather - 100-108 degrees and I have a Trane. Keeps house cool.

[Lurker]

If you’re having problems with freezing you’re probably low on freon. But if you want to replace it I can highly recommend Trane.

[taxcontrol]

I live in Colorado 2,300 sq foot home down just north of Denver. My air unit went out and I replaced with a 4 ton with 5 ton exchanger. Bought a Lennox paid right at $4,000 through Costco. On hot days, maybe the house heats up to 75 if I have the air set to 72. Way better than my old unit.

For your size house I would say your needs are closer to 5 ton with a 6 ton exchanger. You might also want to look into the possibility of a dual zone with two 3.5 ton units but that would require you split your air handling.

[deweyfrank]

bttt

[Hillarys Gate Cult]

Had a Bryant ( heat pump ) since the mid 90s but it died recently. Lasted years longer than average. Replaced with a Goodman. They make many of the parts for the major established old brand names and have the best warranty out there. Power bill went down by > 30%.

[KMG365]

I would go with a Lennox. Made in Marshalltown Iowa for 110 years. We have a Lennox heat pump that was installed in 1995. It runs 12 months a year here in Greenville TX and we have never even had it serviced.

[Secret Agent Man]

Carrier is good. Also York has some good products.

Everything really needs to be sized right. The blower and a/c coil need to be the right size. If the blower is too strong air will be too warm, going over coil too fast. If too weak, the coil will ice up and no cooling.

Often having both units be from the same company makes things easier and if they are both replaced at the same time one part won’t be older and closer to replacement.

[Secret Agent Man]

I read yours and others comments more closely and saw you had a two and a half ton a/c for a 3500 sq ft house. That is way, way undersized. I had a 2.5 ton prior in my house that was undersized for my house and mine is less than half the size of yours. I now have a 3.5 ton and it’s good. You’d need a 5 or 6 ton unit.