achange, my two speed Trane was noticable when it shifted from low to high, I could hear it inside near where it was located.

"Does anyone have any ideas how I confirm the two stage compressor is set up correcty?"

- The amp draw from the compressor will be higher on the high stage versus the low stage. You need a clamp-on ammeter to check curent to the compressor.

The 2nd stage should kick in when conditions require it. If it's hot outside and you knock the t-stat to 69 F (from 75F), the 2nd stage should come on as the setpoint temp will be much less than room temp (75 or so). You should be able to here the condensing unit (outside) go from low to high stage.

I have a pair of Trane 2-stage units (16i) and I can't tell which stage they are in. I have figured out however that they cool pretty quickly to the set point and then stay on at very low speed to dehumidify. My humidy levels are usually in the low 50s and only when I set it on about 71 and it runs at a slow blower speed to try to get to the humididy setpoint of 45% (which it never reaches) does it get below 50%.

I wish there was a light or something that would come on, so you can be sure its working right.

Thanks for the replies. I'll play with the setpoint temp on the t-stat and listen for the change in the compressor outside. Hopefully I can hear a difference. I do really enjoy the variable speed handler and the ability to control the humidity setpoint.

Texas - I don't have any problems getting my humidity down to a 45% setpoint. You must live around Houston?

If you have a thermostat with menu's, check to see if you have basic and advance setting buttons on the stat. I have a 2 stage cooling system and I have these.
Here's how I get to the menu to check to see what cooling stage my compressor is in. Yours might operate in a simular fashion.
Hold in the advance button for 10 seconds. A menu called "Install/Service pops up, highlight "Service" and select it. Another menu pops up and amongst one of the selections, there is one called "AC Status" - select it and the info you desire will come up.
This is assuming you have very simular features as my Bryant thermostat.
Now on another note, Its possible your compressor is behaving like mine. I can force it into high stage by dropping the temperature down 5 degrees from its setting and I would have to leave it there until a comfortable humidity level is reached and then turn it back up to the regular setting. But the system will not automatically go into 2nd stage during hot weather like its supposed to. These two stage cooling systems with some exceptions will always start out in 1st stage and when extreme heat exists, it will switch over to 2nd stage cooling. I suspect that is not happening with your system and if so, then it sounds like a fault between the thermostat commands and the compressor.
Watch your technician closly, he may force it into 2nd stage, do some other checking and then say he cannot find anything wrong. Well, you tell him that it will not go into 2nd stage automatically (when high temperatures exist) and that you expect him to fix it before you pay him for the service call.
This is the situation I am facing with my Bryant dealer. I had to call the Factory regional manager about this and I expect a reply this week. Good luck with yours.

rjordan,
You bring up a good point about "forcing" the compressor into stage 2 vs "automatically" going to stage 2. I'm not the expert but it seems to me that by design it would take a pretty large swing in temperature to get to stage 2 automatically. I guess something like programming the tstat to 80 on the away setting and 74 on return. I would expect my compressor to kick on in stage 1 but switch over to stage 2 pretty quickly to get the room temp down to 74. However, if I'm just sitting at home and have had the AC on all day and the outside temp jumps from a morning 76 degrees to an afternoon 105 degrees, I would expect the compressor to keep up with the incremental increases in outdoor temperature all day in stage 1. I don't have a service manual other than the user guide for my Honeywell VisonPRO so I'm not sure if my tstate has the same features you are describing with your Bryant tstat.

I agree. The compressor should kick in as needed if first stage cannot meet the demand especailly when one can set the desired humidity on their stat.