re: Let's talk about my home A/C unit! So fun!

Let me try to answer your questions:

I have no plans to move any time soon. So, ten years or so, I'd guess.

The house is 4000 square feet. Have 3 units. The problem one is a 5 ton. Not sure of the exact square footage of the coverage of that unit, but its the living room, foyer, keeping room, breakfast, kitchen, dining, utility, one bath and one bedroom. 12 foot ceilings in this area. The 5 ton unit has seemed about right.

ETA: If you think it's critical, I can measure the sq footage.