Hi - I have a 2-story home with dual zone AC and separate Honeywell thermostats. When turning on the heat at the downstairs thermostat, the 2nd story zone is activated and heat is coming out upstairs instead. Help? Thanks in advance.

Well, answering my own question... sort of. It seems like it might be a zone valve problem, but I have looked high and low near my water heater and can't seem to locate it? I even pulled the specs for it and it doesn't mention it anywhere. I do have a central unit in the attic - is it possible there's something there that would play into this?