Trane XL16i System - Stage 2 Switch

[jhw62]

Confused....When my Trane XL16i system switches to the second stage the temp goes up 4 to 5 degrees instead of down. I have a Trane XL800 thermostat that is made by Honeywell.

I have two workarounds to get it back down to normal again:

I raise the temp setting to the temp that is registering on the stat and this will cause the air handler to switch back to stage #1. After I have it in stage #1, I can slowly drop the temp back to 75 degrees.

The other way is to put the thermostat into advance setting mode which shuts down the system. After about 15-20 minutes, I cancel the advance setting mode and the system catches up within 30 to 45 minutes.

I've had my contractor out twice for this issue, but it still isn't fixed. They have seen the problem once when the 24v wasn't getting to compressor to turn on Stage #2. As far as the contractor sales manager is concern, the system is working correctly. I've tried to contact the owner of the company and he always has the sales manager call me back.

Personally, I'm thinking it is a thermostat problem. I'm about ready to go out and buy a new thermostat myself to see if it fixes the problem.

Any suggestions what I should do? Should I pay for the local Trane office technician come out and go over the system? Are specific questions I should be asking the A/C technician?

Thanks your help in advanced...... John

[nina]

sounds like Y2 is not called or wired incorrectly to the ECM control board.

I ran a quick setup test on my climatouch after XL19i was setup, created a program rule for +1 degree above setpoint for start stage 1, +2 for stage 2 (total 3 degrees from setpoint)

after that it was easy to verify stage 2 started by setpoint adjustment down

once that worked, I tested quickly time based stage 1 vs stage 2 by creating rule to start stage 2 after 2 minutes, waited 2 minutes, Y2 was called (and I can see lights on ECM board fire up) and stage 2 started.

[kevinmac]

Something is wrong because the second stage should put the unit into the higher capacity stage. You sure the compressor is actually running when switching to stage 2? It doesn't sound like it. It should lower the temp to catch up and then switch to stage 1 to keep it at the desired setpoint.
Are you using a 2 stage cooling thermo? If so is it setup for 2 stage cooling?

[Edited by kevinmac on 06-12-2006 at 04:38 PM]

[jhw62]

Originally posted by kevinmac
Something is wrong because the second stage should put the unit into the higher capacity stage. You sure the compressor is actually running when switching to stage 2? It doesn't sound like it. It should lower the temp to catch up and then switch to stage 1 to keep it at the desired setpoint.
Are you using a 2 stage cooling thermo? If so is it setup for 2 stage cooling?

[Edited by kevinmac on 06-12-2006 at 04:38 PM]

I'm 99% sure that the air handler is switching for the second stage. I have no way to verify the compressor is running at the second stage, because I have the new digital electric meter and I do not want to open the unit and void my warranty for any reason.

As for thermo, I'm using a Trane thermostat model TCONT803 (three-stage heat and two-stage cool with humidity sensor). The advanced settings option #170 is set to #12 (2 Stage Cool / Heat Pump with Aux. Emergency Heat)

[kevinmac]

I don't have that thermo I have it's predecesor Trane Thermo, but I had to configure the thermo for 2 stage. Is it possible this is your problem.