[stevehull]

A home of this age will have leaky door seals. These are inexpensive to replace and tremendously decrease air infiltration. A great do it yourself project.

Allow the gas water heater to die. I would flush it out, but don't toss it right now.

The energy audit is key. A good blower door test will show you your air leakage. You can blow insulation over the ducts in the attic, but also ask for a test of the ducts. A lot of them were poorly fitted together. If an air leak in in the non-conditioned space (like attic) then this creates a negative pressure within the conditioned space where outside unconditioned air must come in. I often see 15-20% leakage on attic ducts.

Replacing incandescent lights with CFLs is also a must as this will be a very rapid return on investment.

How large is this house? Having two 75K heaters is clearly overkill as I heat a home of 2800 ft sq with just a 2.5 ton heat pump (about 30K BTU). You and I are in about the same climate zone (I am in central Oklahoma).

Your utility company will give you the pitch to upgrade to a more efficient AC unit. But forget about that for a bit.

Find the air leaks (blower door test), button up the house, get CFL lights for everywhere (except very rarely used area like attic or crawl space). Seal and then insulate the duct runs that are outside the conditioned space. Ventilate the attic. Get low flow showerheads, etc.

Just doing the above should give you about a 20-40% decrease in energy costs - and most of it just simple stuff (like replacing door seals with new gaskets).

Have fun! We are here to help you with some of the heavier lifting - like evaluating different AC with SEER comparisons, return on investment and other stuff. But meanwhile, let's keep Momma happy as things are very nervous when you buy your first home.

Let us know your energy test results and we can help evaluate this.

Steve