A/C turns on when heater activates

[captdaveo]

I have a Coleman Lantern 300 TQ. When I turn on the propane heater, the rooftop A/C unit turns on.

Why???? Doesn't seem to blow hot air.

I can trip the A/C circuit breaker to turn it off, and the heater then runs just fine.

I'm baffled, anyone have any insight?

[ewarnerusa]

As @Carl_n_Susan said, there is a setting on the thermostat that is not on "auto".  I believe you go to the "fan" mode on the thermostat and make sure it is set to auto.

[Carl_n_Susan]

This happens when the fan (in heat mode) is set to anything other than AUTO. 

[pbeverly]

Mine does the same thing. I just turn off the AC breaker off when I want heat.  I just assume the thermastat isn't smart enough to NOT turn the AC fan on when I wanted heat,