Noticed something the other day with my thermostat. Couldn't get Zone 2 A/C to run. Didn't want the other one to run while we were watching the tv. Finally I figured it out. Zone 1 was set to furnace. That prevented the zone 2 A/C/ unit from starting. Never even considered that would be the case, but it makes sence. Glad someone smarter than me is designing these things.
