I work for a midwest HVAC distributor (not the brand you mentioned)

I cant speak to the quality of the units you mentioned. But here are some general heat pump questions to find out more info about:

Does your utility company offer any special rate programs for heat pumps? If they do, there may be a minimum SEER needed for that program that is greater than 13. In Kansas City our electric utility company offers an installer rebate and a reduced rate on winter electrical for 14 and higher SEER Heat PUmp systems with a TXV valve.

Are there any state or federal tax credits available to you for energy star systems? Is your system energy star rated?

Is a longer extended warranty available for purchase? Many manufacturers offer 10 year warranty for an additional fee.

Thanks, Julie. I will ask these questions. I was concerned today when I looked up these units online. The 4 ton unit and the 3 ton unit have similar list prices. But the hvac contractor charged me $1500 extra for the 4 ton. Also online it is listed as having a 10 year warranty. But I was told it was 5 year. I hope I am not being ripped off.

The model numbers you looked up are air handlers (the indoor portion of a heat pump system). If you brought up these two models on the web, it is very possible they had a 10 year conditional (registration-required warranty). What warranty you do need to look at is that of the outdoor unit. You should have been provided with more model numbers. The low-end Rheem 13 SEER unit might only have a 5 year parts warranty (compressor and other parts most likely).

How is the installation of the 4 ton system different than the installation of the 3 ton systems? Attic? More ductwork involved?

"Thanks, Julie. I will ask these questions. I was concerned today when I looked up these units online. The 4 ton unit and the 3 ton unit have similar list prices. But the hvac contractor charged me $1500 extra for the 4 ton. Also online it is listed as having a 10 year warranty. But I was told it was 5 year. I hope I am not being ripped off."

Well that's a good question and a fair one I think. I do not work in the hvac field and my knowledge of the industry is minimal, but I can tell you just like any field, there are people out there whose sole intent is to rip you off. Fortunately most of the guys that respond to questions on this forum seem very very reputable and know there stuff so I would take thier advice. I can tell you that 2 years ago I had two heat pump systems go out on me at my home, both were 16 years old. When I started looking into replacing them I was shocked at the cost. At one point I had two different contractors quoting me prices on the exact same equipment.. one contractor gave me a price that was 4 thousand dollars less than contractor number 2. He also told me they would be in and out in 1 day.. Contractor #2 said it would take him 3 or 4 days. Even though he was going to take longer and cost 4K more, I went with him because I had a good feeling about his company. Not only did he own the company, he did the installation himself. Boy was I lucky, last year contractor #1 was arrested for selling top of the line equipment to a school system but installing low grade equipment. I will also reiterate what I've read countless times on this forum, the installation is paramount. I had never heard of the brand my contractor offered so I was skeptical. But he gave me a 10 year warranty across the board and I had him install two 16 seer Air Ease heat pumps. So far I'm delighted.. My house is right at 3000 sq. feet and this summer we have had numerous days that hit 100 or higher ( Louisiana ) and I have only had one bill that hit the $200. Not only that, I'm able to keep my house warmer in the winter than I ever could with my old carrier units. As for the contractor, had 1 issue last year, he came out, fixed it, no charge... so yes, contractor / installation are most important. If you're feeling alittle uncomfortable with a contractor or his proposal, step back and check them out thoroughly before signing on the line... I got lucky and so far it seems I made the right choice and would hate to see you get ripped off. Good luck with your decision.

I'm going to say what a lot here would say.

10 tons is a lot of firepower. For a new home to require that would be unusual unless you are over 6000 sq feet.

At 10 tons, geothermal is likely worth it. I say that because you usually build a 6000 sq ft house on some land (at least in Ark) and can do a horizontal loop that costs less to install and run. Also, at 10 tons, you just use a lot of HVAC, so geo pays for itself more quickly.

That being said, you might not really be needing 10 tons. I had to fight hard to keep the tonnage down but it is worth it in comfort and cost savings.

Next point - 13 seer for a heat pump seems like a bad idea. I mean if you are just getting a/c and don't need it for a long season, go with 13. But a heatpump is getting double use so the efficiencies payback twice as fast. I don't know a lot about Arkansas, but I suspect most parts have a fairly long a/c season. Now there might be mountains that don't so I don't know. Seer 15 is considered to be a real minimum with a heat pump and/or a long cooling season.

Seer 13 equipment tends to have the lowest level of quality parts from a particular manufacturer. Think Toyota Yaris (seer 13) vs Camry (seer 15). The warranties tend to be better on seer 15 equipment too.

Last point - you are on a HVAC forum. You care about details of your HVAC system. You have a little cash (10 tons). Do some research and don't get a bargain basement seer 13 oversized POS. Have you seen your manual J? I spent 50% more than budget on my HVAC system because budget was based on seer 13 no frills stuff.

Thanks for all the help. We do have a long heating/cooling season in Arkansas. We heat or cool almost year round. The house is no more than 4000-4500 sq feet. So 10 tons is more than I need? They originally quoted 9 tons then revised it to 10 ton for an extra $1500 payment. I hesitate to go against their recommendations as if there is not adequate cooling they will point to that.No I have not seen the manual but will do so.

AC is not like a car, in that a bigger system gets you more.

A system that is sized too large will not "stay on" as long as a right-sized system.

If the system is not on long enough, you will not get the dehumidification that you will want in Arkansas. Cool and clammy is not comfortable.

Also, are they doing 3 systems to avoid doing some more complex ductwork?
If you need 3 systems for layout reasons instead of load/square footage, then I think you may want to ask another dealer for their solution to your home.

Things like 2 stage systems with zoning all cost more upfront, but may give you more satisfactory comfort with better yearly op costs.

Oversizing is bad. You need less tonnage.

I would go with higher seer units. It shouldn't be a ton more mone to get the 14/15 seer single stage units.

Again, 10 tons is alot. And why 3 units? maybe try with 2.

Is this a retirement home? In the Ozarks? with a lot of oversized windows? And high ceilings? a large 'great room'?

Not a retirement home, but a regular home. The ceilings are 10 foot on the main floor and 8 foot on the upper floor. No basement. No oversized great room but a kinda open concept.There is a heated and cooled sunroom also 10 foot tall which has windows and is facing north. The AC guy initially proposed 9 tons and then upped it to 10 when he considered the sun room, in which we had increased the area of the window. The house is well insulated and the windows have low e glass. I hope I can get this figured out so I don't end up with a system that is wrong for my new home.

pvel - I built a 4000 sq ft house in NC a year ago. 10 foot ceilings upstairs, 9 ft upstairs. I have 7 tons only to help cover the basement which bumps the sq ft to 5300. We are a bit oversized but 2 stage which minimizes the downside. Our house is oriented East/West which adds some to the a/c load.

My advice. Ask to see the Manual J. Know that your HVAC dealer may not know everything and their primary concern is not getting called back for inadequate cooling. Humidity is less of a concern and utility costs are not either.

Why 3 systems. 2 sounds like it should be fine
North facing windows don't significantly increase a/c load. West is the worst, followed closely by East, then South and then North.

What does well insulated mean? Above code? Energy Star sealing? Attic foamed? Radiant barrier?

People get into trouble building a well insulated home and using HVAC contractors who aren't used to that. This forum is filled with people having troubles from oversized systems.

What is your heat backup system? Electric or NG?