We're looking at a house we'd like to buy, but I'm concerned the HVAC may not be adequate. I realize there are a ton (no pun intended) of variables in sizing a system, but I'd like to give a description of the house and system and see what folks think the likelihood is of this being a problem situation.
The house is about 90 percent renovated, with a brand new never used Amana (Goodman) 13 SEER 5-ton compressor, and a matching gas furnace (same brand/capacity). This being a renovation, the system has never actually been used.
The house is HUGE. It is well over 3000 sq ft upstairs, and there is about 2500 sq ft downstairs that is finished. The upstairs is mainly 8 foot ceilings, but the is a 9 or 10 foot ceiling in the kitchen/LR, and another tall ceiling in the master BR and bath. There are no 2-story rooms in the house. The downstairs is all 8-foot ceilings.
The single 5-ton unit has been installed to service both upstairs and downstairs.
Knowing what little I do about HVAC (I'm in the middle of my first HVAC class), it seems like this system *might* be sufficient for the upstairs, but I can't see how it could service both upstairs and downstairs. Even if it has the capacity, it seems that balancing would be a problem as the seasons change. I don't know how to compare a 13 SEER system to to the 10 SEER (and lower) systems I'm more familiar with, so I don't know if the 13 has some magic that would make it work in this situation.
I realize it's impossible to give an accurate answer without seeing the house and taking measurements, but can I get some feedback on whether this house is something I should consider, or whether I should walk away from it as a disaster waiting to happen?