Mike
Guys, just wanted you to know that the system you installed is working great. It transitions automatically to the gas back-up and then back to the heat pump with no issues. The heat pump maintains the house temp even when below 32* outside, but for warming in the morning when below 32* it switches to gas. Thermostat is working well and allows me to monitor and control the system when away from the house. Probably be a couple more months before the savings on gas are apparent. Again, great job!