To clarify. I just replaced several windows, with Pella ones. I tried to replace at least 1 window in each room, and will eventually replace all of the windows. The new windows and old windows do not seem to have much of a draft, however, I have a chimney that often gets a backdraft,so I am having some cap type things??? put on the clay chimney exhausts on the roof. The home is 3 stories. The 3rd floor used to be an attic, and I had it remodeled into a loft type apartment.The 3rd floor is insulated, as for the bottom floors, I really don't know what type of insulation is in place(whatever they use for stucco and plaster walls). I wouldn't mind paying the heating bill if it was actually warm, but even with the heat turned to 72-75, I'm freezing from Dec.-March. The fireplace is the only thing that warms the place up. It has a blower that kicks out hot air when the fireplace gets to a certain temp..I really don't like the smell of wood, and its messy, so I try not to use the fire place unless it's cold and I have company. Thanks "brickeyee" for the advice on the Space Pak, I'm going to look into it. Anymore suggestions are helpful, keep it comin'!! Thanks to all. :)

Hockeychik: It really doesn't matter what I pay in Maryland because my bills (and everyone else's) are based on many variables including house size, house age, construction, lifestyle, # of people living in the house, utility prices, phases of the moon, etc. Too many variables make up utility costs. If you replace a 1988 80% effficient gas furnace with a 2007 80% efficient gas furnace, you gain nothing in efficiency (but you do get a new gas furnace). If you get a 95% efficient gas furnace, you get 15% more efficient in gas usage (a 15% savings in your heating bill), a variable speed fan in the new air handler, and may qualify for the Federal tax credit that you want. The only "warning" is that a new, high-efficient, gas furnace may require modifications to your flue such as installation of a flue liner. I am not knowledgeable on gas furnaces so you need to investigate this so that you are educated on gas furnace requirements. If your a/c is 19 years old (mine was 21), you can assume that it was a 7 to 8 SEER unit. By going to 14 SEER, you should save about 40% on the cost to run your a/c per hour of run time. It's OK that you are not sure what to do. This is a big decision with big $$ so take your time and think it through. Again, good luck.

$170 is a great price to clean the coil - I'd look over the blower-wheel as well, since if one is dirty, the other is likely to also be dirty, and they both have the same effect - lowered efficiency due to reduced airflow. If the system is otherwise functional, I'd agree to keep it around myself - I also believe the tax-credit has inflated prices - and better, more efficient systems are being released constantly. That "tax credit qualified" unit is likely to become a bottom-shelf unit in a couple of years. FWIW, you didn't mention insulation - a 1993 home in a climate like Dallas may not have much attic insulation. I had cellulose blown into my attic to take it from R-19 to R-49, and the difference in comfort was amazing. It also made a noticeable dent in my cooling bills. If you really want to get some of that tax-credit money, and lower the workload of that existing system, I'd think about blowing in some additional insulation. For my 1800 sq/ft home the cost was about $800 - half of which would come back from the feds with the tax credit.

I agree depending on the cost of repairing it will be easy to decide to replace or repair your split system. A few months back, I heard from my friend she was facing problem with her split system after checking the amtek air reviews she contacted amtek air professionals to repair it and she is happy and satisfied with their service.