replaced 2-ton with new 2-ton but....

stephen123123

I had a 2-ton a/c & heat unit in my 1,050 sq ft one-floor condo that was 15 years old and doing fine until it failed. It was replaced by a Daikin 2-ton unit which, in 93 degree weather, could not bring the temperature below 79 degrees. Yes, the attic duct-work and insulation should be improved, but we are puzzled as to why the new system could not perform equally to the old system. I thought, maybe, the problem is that not enough volume of air is circulating. Any thoughts. The air handler was replaced once with a different one that did a slightly better job.