Quote Originally Posted by motoguy128 View Post
3000sqft in western canada. 4.5 tons combined capacity might still be on the big side. You should have seen some improvement however. But as mentioned, a 3 ton coil with a 1.5 ton condenser will result in a dry coil unless you really, really slow that blower down. I think a 2 ton coil is about as large as you want to go. I'd start by slowing the blower, but long term
you may need to put in a properly sized, matching air handler.

Also, 6CPH as mentioned is way too much. 2-3CPH is better for AC.
Thanks Motoguy (and everyone else taking the time to try and help). The 3T unit has a properly sized 3T condenser (I'm told). The 1.5T unit is new (Rheem) and I saw them install a new Rheem condenser. I'd be shocked if they mis sized it again. This is a bit maddening. Outdoor air temp is 23C today. At my office, when I arrived, indoor air temp is 23C/RH = 38%. When I left home the house was 22.5C/RH=59%. Both systems were cooling to the same exterior conditions and I used the same hygrometer to take the measurements. Not a professional tool though - a $20.00 unit from Home Depot.