My 13 year old 4 ton 8 SEER Trane system went out 3 weeks ago. My house is 2300 sqft, brick, one story and in Dallas. I opted to use this opportunity to replace rather than repair this system. Long story short, I selected a reputable vendor and chose a Trane XL16i 5 ton system and XV80 furnace. The vendor performed a load calculation and advised that the home was on the edge of a 5 ton system, and he beleived a 5 ton system would cool the home better.
The install was started on a Monday morning and due to install issues did not finish until that Friday. The install issues varied from a miswired thermostat and a miswired furnace to a defective molex plug on the outdoor units fan.
Fast forward to 2 weeks later. The system has yet to adequately cool the house. If we set the thermostat to 75, the AC can only maintain at best 79-80 degrees. This seems to be the case regardless of temp. When we adjust the thermostat to 72 at night, the system can only reach 72 at about 3 to 4 am in the morning.
My question is, is this typical performance, or is there something seriously wrong with the install? I lean toward the install/hardware since we have had so many issues, but also other comparable age homes with older systems can maintain a great comfort level that this unit has never touched. Further, the old system outperformed this system hands down (which I was told it would be quite the opposite).
Any input or advice you could provide on this subject would be much appreciated.