I have a (2008)5 ton Trane heat pump XL14i downstairs and a (2011)3 ton 2 stage heat pump 16XLi upstairs both of variable speed air handlers. Prior we had two Contractor Grade Carrier units (1993) R-22 original units we have a 1993 home. The new units don't seem to cool down the house like the R-22 Carrier Units especially when the temps. are 103 and abovt. They didn't even cool down the house to 79 when it was 110-115 it only cooled it down to 82. I live in Phoenix and today it's 108 with 17% humidity partly cloudy. I typically set the AC at 79 and it will meet that temp. unless we get up to 110 and above. But if I set it to 78 degrees the inside temp. goes up to 80 not down.. We checked how cold the air was coming out the vents and it's coming out at 70. That seems too high in other words not normal. Our filters are clean. In April when Arizona was cooler the air came out of the vents at 55. I'm so unhappy with these Units. I've talked to others with other brands and they don't seem to have trouble cooling their home down to the set temp. I've had the Freon checked and they said it's fine.
I would think these units would be able to keep up with Arizona summer temps. Any suggestions on what I can do or what I can ask our AC company to check. I just get the answer of "IT'S HOT OUT" when I talk to them or how the 410A runs at high pressures and doesn't do well with high humidity which it's not high now or high temps. Had I know that I would have purchased R22 units again as it was an option but I was told we have to change over to 410A eventually. I just looked and now my Thermo. says it's 81 in here and it's set to 79. I have a stand alone thermo. and it shows the same thing. Basically these units can't handle AZ heat.
Could have something with the install gone wrong perhaps we can check something on that. Oh to add we had a new coimpressor installed in April, 2011 on the 2008 unit it sounded like a Mag Truck and the motor went out in the Air Handler this past weekend. Not impressed with our purchase from Trane at ALL.