how do the current sized units perform? oversizing is a bad idea.

what part of the country are you in?

So your saying your outdoor compressors are single stage? They aren't too stage compressors? Non variable speed fans are still multispeed.

Variable speed fans on the air handler cost more and can be used to better control humidity and save a bit on energy.

Non variable speed fans these days are still energy efficient and cost less money. They aren't as 'top of the line ' as variable speed fans.

I live in South Florida. My contractor did the calculations and that is how he came up with the new sizing of the new units.
Yes, the outside units are single stage.

Also, let me know if $10,800 for both systems (before rebates) is a fair price.
This includes relocating everything so my air handlers are now in my garage. Currently there are in my attic. We think by relocating them to the garage that this will decrease my electric usage.

how did the old units work? Were they keeping up? You don't want to be oversized. Its better to be appropriately sized and have units that run constantly.

One thing I know is that my electric bill is significantly more than most of my neighbors. It's always been that way since I moved into the house. I don't keep the house any cooler than they do.
One of the units works OK but on warm days it's hard to cool that part of the house. The other unit has issues with some rooms in the back of the house.
The guy that did the calculation took all window measurements and other data needed and used a program to do the sizing.
My feeling is with all the rebates, it's would be better to get these larger units, get the air handlers out of the attic and install the above equipment.

whatever

I find it interesting that dealer plans to upgrade sizes but you have said nothing about whether ductwork system b oth supply and return has been inspected thoroughly to see if it can handle additional CFMs. Just as important as size of systems.

what size heat strip for each system?

here are the numbers. BTW, AmStd is excellent HVAC.

3436397 Active Systems ALLEGIANCE 15 AMERICAN STANDARD, INC. 4A7A5042E1 4TEE3F40B1 40000 13.00 16.00

1421684 Active Systems ALLEGIANCE 15 AMERICAN STANDARD, INC. 4A7A5048A1 4TEE3F49B1 48000 12.00 15.00 1

these are AC condensers, not HPs correct?

the 3 1/2 ton system qualifies for tax credit, the 4 ton does not.

what stat was quoted?

"We think by relocating them to the garage that this will decrease my electric usage." That's an interesting statement.

IMO

my error

here is the correct matching number on the 4 ton system.

and yes, it qualifies for tax credit. it should be noted that the cooling BTUs are short by 3000 BTUs for a 4 ton system.

3938655 Active Systems ALLEGIANCE 15 AMERICAN STANDARD, INC. 4A7A5049E1 4TEE3F49C1 45000 13.00 16.00 1

IMO