The 'experts' measured the house and checked the insulation and then
told him that the manual whatever showed that he required a 2 ton
(24,000 btu) system.

He ended up with a free 5 ton (60,000 btu) system that has kept him
very happy. The 'expert' hvac guy was not very happy, though.


That's great if you like that "cave clammy" feeling. It will be a cold
house that still has all the humidity since the oversized unit won't
run long enough to pull the humidity out. That may work fine in
Arizona but here in Florida it will make it "rain" in your house as
the humidity condenses on things..

I would have used a 3 ton if the "experts" said to use a 2 ton. Having lived
in Las Vegas for 15 years, I learned early on that too many "experts" and
contractors use the one ton per ~400 sq ft rule, and you end up with an a/c
unit too small to cool your house when the temp tops 115 (which is does for
weeks on end in July and August in Vegas). I replaced my 3 ton unit with a 4
ton unit, and I was in a/c heaven! However, Vegas is quite dry and quite
hot, so we don't need much dehumidifying action - we need extra cooling.

My office needs a 5000 btu a/c according to btu/sq foot charts. A 5000 btu
a/c runs and runs and runs during the peak of the day, it doesn't cool that
well. I now have a 6000 btu unit in the window sill The extra 20% is all it
takes to make the difference between sitting here sweating during the heat
of the day, and enjoying a nice cool office.

Anyone else care to comment on whether you go with the recommend size, or
upsize 20% or so? IANAE, and my limited experiences are certainly not
representative of a/c installs in general.