I have a two story (3/12 gable roof) house in Mesa, AZ with a 5-ton packaged heat pump on the roof. I am having the unit replaced by an HVAC pro and have a few questions.
1) Is it better to use the current sideflow w/elbow configuration, or switch to a downflow w/curb configuration? It seems like most companies want to go sideflow with an elbow.
2) Does brand really matter (besides Goodman)? I'm currently looking at comparable American Standards and Rheems (14 Seer, single stage comp, var blower).
3) I currently have two 14x25 stamped filter returns, one on each floor. It'll be hard to change the size of the 1st floor return, but I can easily have the second floor changed out to a 14x30. I can also select the bar style grills. Will one 14x25 and one 14x30 bar face return be okay for a 5-ton unit?
4) How do I find a quality installer in Mesa? There aren't any listed on the locator map.
Some other details: My house was built in 1978. It has rigid metal ducts. The airflow to the 1st floor is poor. The supply ducts are average leakage. The return is a little above average leakage.