I have recently purchased a trane xl16i heat pump system with a variable speed mv90 two stage furnace backup. I paid to have this system zoned and have a tz4 Honeywell zoning board with trane tcont803as32 thermostats. My installer is having a very hard time getting this system up and running. After talking with Honeywell, They recommended having the tstat control the staging of the hp and having the furnace controll the staging of the backup because the tstat only controls 3 stages of heat (I am a little confused here). We are using the fossil fuel kit integrated in the zoning board. My question regards around the programming of the thermostat. 1. What is the system type? 3heat/2cool hp with aux heat or 2heat/2cool with no aux heat. There are no heat strips. I am guessing 3/2 w aux heat. 2. what is the difference between Aux heat and em heat? 3. if 3/2 with aux heat then I assume that setting 260 (cycles per hour for 3rd stage heat) should be set to 3cph used for 2-stage fossil fuel forced air systems. 4. There is a test mode for the heat with an option labeled (3) that "3-stages 1,2 and 3(Aux Ht) on. This would run the furnace and hp at the same time. That is susposed to be very bad right? Kevin

My Lennox heat pump keeps shutting off, particularly when it gets to be kind of cold outside (<40 degrees). There is a reset button I can push and when I do, it starts right back up. I had someone look at at and he thought the pressure was getting too high. He checked the pressure and it was fine and put it into and took it out of defrost, to make sure that was working OK, and it was. Anyone have any other ideas of what the problem is. I should note that it is about 19 yrs old, so I'm not surprised it is having problems, but I'd like to ride it out another year or so if possible. Thanks.