I have an 11 year old two story house that has a single 5 ton Carrier that had a butchered installation that wouldn't pass code today. The system provides the proverbial hot up year around! I have had contractors speak about zoning systems versus installing 2 seperate units. Besides the obvious of more expense for two units to maintain and slightly higher total cost...I would appreciate any feedback.
Units I'm considering are Ruud, Amana & Trane (14/15/16 seer?). Thoughts?
What is the significance of re-using the copper freon line changing from R22 to 410a?
Extended warranties --worth their while?
Better or worst zoning systems with digital programming?