I have been shopping for an HVAC system for a couple of months. I think I have made my final decision. I went under the assumption that overall quality of the top brands is similar. I entertained bids from 2 dealers for Carrier, Trane, and American Standard. After much deliberating I went with the Trane. I am having buyers remorse and since I still have time to cancel the order I am looking for reasurance that my decision was a valid one.

I just purchased this home. I did so knowing that the HVAC system needed to be replaced. The existing Payne A/C is completely shot and the furnace is 35-40 years old.

The home is in NE Ohio and 73 years old. It is all brick and aproximately 2000sf not including the 400sf finished basement. There is insulation in the attic but I assume there is no insulation in the exterior walls or at least it's probably very ineffective. The windows are single pane, but there are storm windows on all of them. (I can't bring myself to change the windows they are all leaded glass.) We usually heat to about 65-67 never above 70 and cool to around 77 we go all the way down to 74 if we've been working in the yard all day and are hot but not regularly.

All of the contractors did a J and came up with the same #'s for requirements. 80000btu when going high efficiency and 3 ton A/C though one came up with 3.5 ton. Which would mean 4 ton with Trane. The existing furnace is 160000btu and the Payne is a 3 ton.

I was originally shopping for a high eff furnace and 13 SEER A/C. The subeject of a hybrid system came up and seemed to make sense. This is where some discrepancies between contractors started. The overall consensus was that a VS blower was needed to really make use of a HE HP. There was one salesman that said a 2 speed blower was good enough. The major difference was half of the contractors said go with 80% a couple said 90% and one said 95% furnace.

I decided not to go with an 80% furnace because when I use the gas to heat in my opinion I want to be using as much of it to heat as I can. That and if gas becomes cheaper than electric again I will still have a HE furnace. Is this good logic or am I better off with something like the XV80 from Trane? It still has the VS blower but the cost difference is minimal (relatively) but I would have to go to a 100K btu model instead of the 80K with the HE furnace. That is why I chose the system I did.

I decided to go with an 80K btu Trane XV95 and paired it with a 3 ton Trane XL15i HP (410a). The dealer said in his opinion the XL16i was not worth the cost for the increase in performance. Added are an Aprilaire 600A humidifier and an Aprilaire 5000 EAC. The control will be a HW pro. The contractor said the coil will be matched but didn't actually mention the model number. This is my one point of contention. PLEASE CAN YOU POST THE PROPER COIL I NEED TO LOOK FOR. (sorry for the caps just wanted to catch the eye of any glancer.)

The installed price is $9895 though I do get $300 back from Trane through a mail in rebate. So it's actually $9595. All of the quotes I recieved were in this ballpark, actually slightly higher, and the other manufacturers were close too. I was originally going to go with an Aprilaire 4400 but I upgraded. It cost me an extra $200 to get the 5000. Is it worth the upgrade? I have read good things about the 5000 but I am not positive I made the right choice. I have dogs and do suffer from some allergies tied to dust and pollen. If I am not mistaken there is also no prefilter to clean so it is easier to operate. Is this true? Is there a truly noticeable difference between the 4400 and the 5000?

I guess I am just trying to make sure the system I bought really is the best. Are there any changes that I should think about before they order the equipment on Monday? You all seem knowledgeable so I wanted a 3rd party informed opinion to help settel my mind. $10K is a lot of money and I want to be sure it's well spent.

I do have a few questions though about set up. What is the ideal set point for the HP. The answers I got from all of the contractors varied fairly widely. They went from 15 degrees to 45 degrees. Where does it start to become inefficient to run the HP? Also, when setting up the HW Pro what is generally a good setup? How much time should I allow to recool or reheat from the empty setting to the home setting? How many degrees makes sense to offset? Again we usually aren't cooling and heating that much anyway. Is 55 about right or should it be 60. I don't want to lose the efficiency I gained by working the crap out of the system to keep changing the temps. Another question I have is whether I should run the fan all of the time year round or only when the system is running?

Sorry the post is so long. I'm just looking for some input I guess. Any input would be appreciated. Thanks in advance.