I just had a 4 ton 16i, and variable speed air handler installed, but unfortunately, the people who installed it are not inspiring me with confidence that it's set up properly. For example, they installed the air handler with the default switch settings, which don't allow the enhanced mode to work. They only changed this when I called them back because my variable speed airhandler wasn't doing anything but turning on full blast. They would have left it that way forever if I hadn't caught it, so I have to wonder what else they did wrong.
I've tried to confirm the way they wired it up, but it doesn't seem to conform to any of the options in the installation book. I could post the wiring at the air handler if needed, but I haven't checked the other end of the wiring at the thermostat, or outside unit.
My first, most basic question is about the 16i's two stage compressor. I was under the impression that it can run at two different speeds, or capacities, almost like a true dual compressor unit. Is the switching for this two stage feature done internally to the 16i, or does it have to be treated by the thermostat as a dual compressor unit? There's a setting on the XT500C thermostat that has the option of "one cooling cyle, and 2 heating cycles", or "two cooling cycles, and 3 heating cycles". Mine is set to the first choice, but I wonder if the two stage compresser means it should be set to the second.
The next question is whether the air handler fan should run slower when the 16i is in it's lower "stage" mode? At the moment, mine seems to do just what the book says for enhanced mode, where it ramps up to 50%, then 80%, then 100%. This moves a lot more air than our previous unit did, and can get pretty noisy. My hope was that this variable speed air handler was going to be very quiet most of the time, but that hasn't been the case so far.
Any answers to the staging question would be most appreciated.