It is not a good quote because the equipment seems over sized based on the information you have provided.

Your house is big, but I think 7 tons of cooling for your location is overkill. What is area of the first and second floors? Why aren't you getting a quote for a high efficiency (95%+) furnace? I find it a little hard to believe you need a 110,000 BTU furnace just for the first floor.

The equipment you have been quoted is very good. My suggestion is to find a contractor who will do a load calculation. You don't want over sized equipment.

The first floor and basement total about 3100 sq ft. 300 sq ft is unfinished but still has HVAC. Upstairs 1300 so overall total = 4400. Main floor is a fishbowl with a ton of windows.

Seems other Carrier quote and the Trane certified people gave the same tonage so I trusted it. Trane was too expensive though for the 18i & 20i.

Also, we live near the hills/mountains so we get blasted in the winter with wind. Also have east west exposure so the house gets hot, especially with a sunroom in the summer. So cold in the winter, hot as heck in the summer unfortunately.

The basement area does not contribute to the heating and cooling load if it is below grade. It takes very little to keep a basement warm. In the summer the basement is naturally cooler than the first floor.

What is the breakdown in area between the first and second floors?

The price you received for the Carrier quote seems fair. I would hate to see good equipment operate poorly because it is over sized. Ask the contractor how the sizes were determined.

After looking at the tax assessment database, looks like main floor is 1800, total basement is 1560 and upstairs is 1198 (not sure how exactly accurate it is). We have additions on the main floor that don't carry over to the upstairs sq ft, and some main fl area doesn't carry over to the basement sq ft.

I am familiar with the area/climate, and I too believe that the equipment is oversized and will not perform optimally, especially the first floor system. Very common (and outright wrong) practice in the residential HVAC industry. I would not move forward without a load calculation. When you are given a written copy of a load calculation, post it here if you can.

The 005 is the better matching fan coil size for the upstairs system. Same physical size as the 003, so space isn't an issue. I am also quite certain 15 kW of strip heat for the upstairs system is excessive as well. Sounds crazy for an upstairs heat pump system conditioning ~1200 sqft. I have 15 kW of back-up strip heat for my 4 ton heat pump system, which more than adequately conditions my entire house (~3000 sqft total) in MD.

You've been quoted quality equipment at a fair price, I would only caution you to verify that the equipment is properly sized to your home's load. This results in the most efficient, reliable, and comfortable operation. Just as important as finding a qualified and competent company to do the work and provide exceptional service following the installation.

This post was edited by ryanhughes on Sat, Sep 7, 13 at 19:32

Top of line equipment but strongly suspect oversized on both systems.i would want pleated filter box cabinet for both for indoor air quality and protection of evap coil and blower motor.

Request load calculation heating and cooling for both zones. Discuss design temperatures with your dealer.

IMO

What large city do you live near so we can get an idea of what your summer design temperatures are.

I'm going to list a free online load Calc, use it to do each floor separately; it does not do room's separately and, it does not save the work when you finish. Therefore, worked a Calc a number of times until you think you have everything right and then print it.

I doubt very much that you need 7 tons of cooling; it is a big mistake to oversize equipment. Considering the size of your home were it me I would consider having a home energy efficiency audit done to see where you can make reductions in the heat load,

Reducing the size of equipment improves the duct system airflow efficiency and helps on the proper sizing of the return air filter areas.

I have been using Dragon Speaking Naturally 12 to type these posts & it sometimes adds a wrong word I don't catch when editing too fast.

Here is a link that might be useful: Free online Whole House Load-Calc

Thank you everyone for the replies.

Nearest city would be DC. We're out near Leesburg.

Seems every quote we get (Trane and Carrier) are the same tonnage. These are certified contractors off carrier and trane site. Maybe I'm not giving enough info on the house, or the comment above about the commonplace practice of quoting oversized equip is happening here?

zman92tt:
have you got the system installed by chance? how did it go? and would you mind share the contractor contact info? i live in northern va and look to replace my 2-zone hvac systems too. thanks.