Our house was built in 2003, and roughed in (if that’s the correct term) for central air—we have ducts, wiring and piping between the side of the house and the attic. We had five contractors out to give us an estimate on installing the compressor, air handler and whatever else is needed. They all took measurements of the rooms and noted where the vents are. We’re expecting prices this week, but their quick suggestions and overview differed in a few respects.
Aside from reputation and references, what are the key things we should be looking for or preferring? For example, one suggests hanging the air handler from the attic’s rafters, others were putting it on vibration pads. Is there a significant difference? Does SEER rating make a difference aside from the cost of energy? One company wants to do a pressure test (or something like that) on the vents to “balance the load”—is that crucial? What else should we be familiar with before choosing a contractor? Any horror stories to share or lessons?