Hot Time in the Summer - New AirCon Unit?

None | 06/21/12 | GRRRRR

[GRRRRR]

It is summer for sure. Colorado is experiencing 90-100 degree F days in the north east plains. Forest fires, high winds and dust complicate the time we can have the windows open as even at 80Deg in the house, the low humidity makes it comfy.

The Carrier AC unit for this house (3,500+sq ft, 4BR, high ceilings) has had issues since I moved in. Refrigerant leaks and an electrical issue. Now, with the heat of the summer coming back, the AC unit can't keep up again.

I've cleaned the unit outside, replaced the inside filter and am still getting some freeze up on the line going into the plenum.

Air temp coming out varies from 60-70 DegF.

I think the unit is under rated. Can't find out what tonnage it is either. Model is 24AB300 which I can't find either.

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

Pricing on line ranges from $3-$8K as defined by size and install costs...LOL!

Finally, would they have to replace the exchanger in the furnace too?

Thoughts? Tks. G.

[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 !

[GRRRRR]

Hey AP, thanks man, good to hear ya!

House built in 2006, original HVAC. Only change is the full finished basement, er...lower level.

All vents down there are shut.

Carry Onward and UP!!

[Marcella]

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

[Copenhagen Smile]

Hahaha!

[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%.

[dragnet2]

3500+ sq ft??? Are you the governor of Colorado?

As energy cost rise, so will the popularity of smaller homes in nice areas. In fact, it's already happening.

[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.

[ATOMIC_PUNK]

Good to hear from you too buddy the best to you and yours

Ya gotta remember cold air falls if you have ceiling fans reverse them to pull the cold air up off the floors and keep lower levels doors closed

get into where your A coils is that's the keys shut off your unit and let it thaw out take a squirt bottle of Windex and spray down the coils then use a strong shop vac with a brush attachment gingerlycleanall the dust out of the coils Windex will loosen it up so it will pull free from the coils ...

Next if you can unplug the squirrel cage and pull it out clean the dust off the blades real good dog and cat dander can really slow down the cage speed hence it will not cool your house efficiently i recommend doing this twice a year for the cage and change your filters once a month ....

Hope this helps it will keep your house allot cooler

remember don't smash down those fins on the A coils because smooth airflow through those coils is a must for a cold house in summer !

catcha on the flip

[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.

[Secret Agent Man]

It also can freeze up if the blower is set too low, the cooling coil will freeze up as the air isn’t flowing by it fast enough.

[GRRRRR]

Happy Fried Day to AP and ALL!

Mercury hit 105 at the house today and the AC seems to be handling it just fine.

Cleaning the filter and stuff seems to have helped very much. AC output air temps ranged from 61-64 DegF all day, house stayed nice and cool.

Thanks for everyone’s input and have a FINE WEEKEND!

G