As a property inspector, it is my policy to turn all of the AFCI breakers "off" at the beginning of an inspection. (vacant buildings only) Obviously, by doing this, I can check to see if the sleeping rooms are indeed wired correctly. Much to my surprise, when I flipped off the AFCI breakers (test button) the HVAC systems stopped working in both locations. (3800 sq. ft. interior) The explanation from the builder is that the HVAC systems are required to shut down if the AFCI circuits "trip". I have never hear of such a thing. Is this true? It was my impression that HVAC circuits are "dedicated" and not to be combined with other circuits. Where am I going wrong?