Heat pump sizing
I have a 1500Sq ft Home built in the late 60's. Currently has a 2.5 ton A/C central air and 60,000 Btu propane furnace. When propane went to $2 a couple years ago I added a 60kw electric duct heater and switched my home to all electric. Saved a bunch of money on heat bills. My question is the A/C unit is really old and I want to upgrade the entire system getting rid of all propane etc. With a Air to Air heat pump do I need to size it for the 60,000 BTU or for the 30,000 Btu A/C load? I live in Northern Iowa. Why would there be such a large difference in the heat/cool sizes?