Post the model number of the outside condenser. The should reveal the size. If you are considering a 2-stage model they only come in whole ton ( 4, 5 ton) sizes.

Model 38YCC042360. What does 2 stage mean? Thank you.

Two stage runs at (typically) 70% or 100% of capacity as controlled by the thermostat to better meet variations in the cooling load (and for better humidity control). They cycle on at low stage and switch to high stage if the thermostat determines it's necessary to reach/maintain the setpoint.

There's also variable speed that operate across a larger range. My parents have a variable speed that adjusts itself from 40% to 100%.

Two-stage is more $$$ than single-stage. Variable speed is accordingly more $$$ than two-stage.

Hi, Paula,

Based on the model number you supplied, your system's rated capacity is 3.5 tons of refrigeration. If the system has provided adequate cooling, I'd recommend replacing it with a similar capacity system.

Your outdoor condenser sounds like a 3.5 ton (42,000BTU) while your indoor coil/air handler sounds like a 4 ton (48,000 BTU). This is often done to improve efficiency (very slightly). If your present system is working fine, I wouldn't go to a 4 ton or 4.5 ton condenser - I'd stick with the system as presently configured.

Two stage condensers only come in one ton increments so your 3.5 ton condenser is a single stage.

Thank you all so much - I think I (somewhat) understand all of this now. AustinAir, I will definitely check out your video - I am in GA so heat and humidity are definitely my uses. In fact, I rarely run the heater since I have a gas fireplace for the den and use a portable in the bathroom when dressing. The dogs have their own fur coats so they don't complain!

Getting a 3rd quote this week and maybe now I can ask better questions and get acceptable answers.

Thanks again, I am sure I will be back with more questions.

"There are a few mistakes. First mistake is that manufacturers do not make a 4.5 ton AC." I'm not sure what products the OP was quoted, but a number of manufacturers offer 4.5 ton (54,000 BTU/hr.) split systems including (but not limited to) Rheem, Goodman, Pioneer and Gree.

the first company quoted a 3.5 ton, but the next one said I could go with a 4.5 ton based on some "heat analysis" they did but they quoted it as a 4 ton so that I would not need new ductwork.

The equipment you have (38YCC042360) is a Carrier heat pump. I suspect the second quote determined the heat pump size needs to be 4.5 tons in order to meet the heating load requirements. Given that you are in GA I am skeptical if this is accurate.

Charles,

Manufacturers do not identify a 54,000 BTU AC as a 4.5 ton. It's considered a 5 ton... if you drift down the size spectrum what other non conformities will you find? Plenty.

Maybe once you get down to 2 or 2.5 ton the sizing is a bit more accurate in terms of 12,000 btu per ton. (depending on many, many factors and differences among manufacturers, models, configuration and so on.)

As an example: This is for an entry level machine for 2024 ( a new model since the SEER2 change.)

Here you will see they list all "nominal cooling capacities": Where is the 4.5 ton?

click to enlarge it:

Most of those who claim this isn't rocket science quit here. Take those listed model #'s to the chart below (the last 3 on the right of the chart above).

I only show the tail end of three sizes of the right hand side of the above chart to show you none of them hit the nominal cooling capacity of the picture above at design operational Temperature which is 95F (out door ambient)

However this chart shows what happens under various outdoor ambient temps and the sizing of the particular unit in question. ( It's all science and math, some will just say "it's not rocket science" and argue for? All I could do is guess here why a builder gets involved in HVAC commentary when he has HVAC contractors on speed dial to do the work for him.)

click to enlarge

So this should show you the scientific nature of your poor little AC and that truly there is no equipment at 4.5 ton. Some manufacturers may do it differently... but due to science and changing outdoor ambient conditions they all go up and down in capacity in relation to what the outdoor ambient temperature is.

Those that spend most of their summer at 80F outside ambient don't have much to squabble over. Those of us in the south, not so much.

I service the Katy, Texas area.

Manufacturers and distributors label some 4 ton or 5 ton capacity systems as 4.5 ton nominal capacity, but there are indeed systems designed for 4.5 ton capacity requirements (a 5 ton system is 11% oversized for a 4.5 ton cooling load.) Here's a link to 4.5 ton capacity Rheem systems available from one supplier https://www.kingersons.com/4.5-ton-air-conditioners-and-heat-pumps.html If you decode the model numbers, you'll see some are 56,000 BTU/hr which would be a 4.6 ton system. If you want a system rated at exactly 4.5 tons, here's a link to one such system from Haier https://www.geappliancesairandwater.com/appliance/Haier-VRF-54-000-BTU-Air-Handling-Unit-MVAX054ME2AA I don't know if they use Copeland's scroll compressor, but Copeland makes one that is rated at 54,000 BTU/hr (4.5 ton) capacity. You can also get 4.5 ton ductless mini split systems from a wide variety of manufacturers, but the OP is interested in a ducted split system.

"....but due to science and changing outdoor ambient conditions they all go up and down in capacity in relation to what the outdoor ambient temperature is." Any high school physics student worth his salt knows that the performance of a system changes as a function of operating conditions. There's no novel insight there. However, the nameplate capacity of an air conditioner or heat pump is evaluated at a particular set of conditions specified in the testing protocol (AHRI Standard 210.240-2023) Doing so allows the capacities of various residential HVAC systems to be directly compared. A 4.5 ton rated system is one which removes 54,000 +/- 500 BTU/hr. under the specified testing conditions. Yes, they do exist.

Misleading Charles.

Because what you posted is not from a manufacturer.

The link to the Haier system is a manufacturer's link. Haier is the number one brand of air conditioners in the world. They've owned GE's appliance business since 2016. If you'd like a manufacturer's link to information about Copeland's 54,000 BTU/hr (4.5 ton) compressor here you go:

https://www.carrierenterprise.com/product/1402917229899/copeland-scroll-compressor-r410-refrigerant-54000-btu-capacity-208230-volt-single-phase-zp54k5e-pfv-830

LOL. I'm not arguing the 54,000 BTU. You claim Haier is the #1 brand in the world, then you go and post a link from CE (carrier enterprise). You want us to believe Hairer is number 1 without providing credible information. Gee what else is new with you Charles? (Mr. Don't worry I have an HVAC contractor on speed dial.)

For Haier to be the number 1 brand they are more or less out to lunch in my area. GE got out of HVAC in the 80's when they sold out to Trane, a few years later (in the 1980's) American Standard bought Trane / started manufacturing American Standard units.

If GE is involved in anyway HVAC today, it's a licensing play where they just license their name to a manufacturer of xyz stature.

If you use a 54,000 BTU AC model as a 4.5 ton, what then do you use for a 5 ton? Certainly you can get closer to that 60,000 BTU by selecting a different model, but that is NOT the question here Charles.

If you look to the "nominal cooling chart" I provided you above your mistake is clearly identified.

If you select a different model to "get closer" to the 60,000 BTU mark those cost more. Contain more refrigerant so when the Red Herring refrigerant ban starts taking hold next year?

GE isn't going to save you Charles.

The fact that Haier may not be the dominant brand or even available in your market doesn't mean they're not a player in the world HVAC market. They have a big presence in Europe and China. You can purchase Haier appliances in big box stores in my area. That said, the point is that 4.5 ton HVAC systems exist; ample evidence has been provided to support that claim.

It's well established that cooling system capacities vary as function of temperature. Whether a particular 4.5 ton system from a particular manufacturer is suitable for a particular application is why ACCA manuals J and S exist. The problem is finding someone who actually knows how to use them.

ha, ha, ha. It's a Chinese manufacturing company Charles.

The size of 54,000 BTU in question is denoted in nominal cooling capacity as a 5 ton. You can make it up as you go long that doesn't make it right.

I told you why it's done the way it's done. But you'd rather argue about a job that you only look at from the outside in. That doesn't make you credible with what you put here Charles.

Because 1 minute you tell us what? Only to then turn around and say something entirely different. When the story continues to change? I think most people can recognize those warning flags for what they are. Certainly not you Charles, because you'll just start to argue about something else.

That is your M.O. (modus operandi)

The evidence speaks for itself, Ray. Have a good day.