Heat pump with 2nd/3rd stage gas

[kwagner]

I currently have a gas furnace. I want to remove the gas furnace and replace my system with a 13 SEER heat pump with 2-stage gas furnace as 2nd/3rd stage heat. My problem is that I have a 3 zone Trol A Temp system in my house which makes it very diffucult for the wiring. How the heck do I lock the heat pump out at 40 degrees. I cant use the new touchpad T-stats because I don't have enough wires at all 3 thermostats right now. Too diffucult to pull new T-stat wires and too expensive to replace all thermostats. What is out there that will do the job on a multizone system.

[BaldLoonie]

Replace the panel with a Honeywell TZ-4. I think that will work with your old dampers but better have your dealer check. You can use conventional 4 wire stats. Tell the panel you are using dual fuel, put an outdoor sensor on the panel, tell it what temp to changeover at. It is one or the other, not both. If too cold for heat pump, it switches to gas. Tell it to stage based on % of zones calling. Friend has a 3 zone house. Takes all 3 zones calling to get high fire.