Hello -

I am trying to find some information on what we need to do to replace our failing residental HVAC system. Here is what is going on - does anyone have any comments or advice?

My wife and I moved to Raleigh, North Carolina nearly three years ago. Our home has a 15 year-old, 3-ton outdoor Trane HVAC unit – the kind that both heats and cools. We replaced the rusted out heat exchanger soon after we moved in, but now the A/C coil has gone out. They are rusting through and freon escapes, causing the coils to ice up.

Our HVAC guy has told us that replacing the entire unit will probably be the best thing for us to do because the cost to replace the coil (and condenser, which we would do at the same time because it is probably going to go soon, too) would be 2/3 or more of the cost of a replacement unit. We finished off the attic and thus added space; we probably need to move up to a 3.5 ton unit (the house now has about 2,250 square feet of living space). From what little I know about SEER, I guess we are looking at a SEER 13 Trane or Lennox unit. We really like our HVAC guy, and as he is a Lennox dealer that may well be what we wind up with. But...

We don’t know anything about this stuff. We don’t know if we should get (a) just a heat pump or (b) a combination unit or (c) separate units (an A/C unit and a furnace side by side). We don’t even know if we can use a heat pump alone in North Carolina, or whether we would have to supplement it with a furnace. Being a bit cautious, we would like to better understand what our options are, and what might be the best choices. (And unfortunately, cost rules out a geothermal heat pump!)

If any of you folks have the time and inclination (not to mention the experience) to comment to us. we woukd relly appreciate hearing what you have to say!

Many thanks...