We live in Texas, and these days its 103F-110F outside. We keep our thermostat set to 78F during the day and 76F at night. In this heat it is struggling, and the temperature climbs through the day until at about 6pm its 84F despite the unit staying on constantly.
I measured the temperature at the intake and one of the vents, and the difference was 21F (78F-57F), which I believe is a good temperature differential. I was advised that it must be entire insufficient capacity in our AC unit, or poor insulation, but we've had quite a bit of insulation work done so I don't think its that. Our home is 1,700 sq/ft.
So we got a local AC company that had good reviews online to come and look at it. This is his diagnosis "verbatim":
"System is mismatched, 3 ton condenser, 50,000 BTU Furnace with 4 Ton Coil".
It seems that whoever installed the system in the first place, and possibly some total morons hired by our home warranty people who replaced our furnace last year, have mismatched the various components of our system.
The cure? We'd need to replace our entire system, at considerable cost.
The AC guy seemed competent, but I have to say that it makes me a little concerned that the remedy just happens to be the most expensive possible option.
Is this guy taking us for a ride or do we really need to spend this much to fix our system?