My new home has ductless wall heaters (Cadet specifically). I want to add a new wall and install another heater in it. In checking my panel, I see that the seven original heaters are on four dedicated circuits; each being 240V, 30A. I want to tie the new heater on the line that only has one heater on it currently. However, in purchasing a heater and checking all of the current ones, it seems that the wiring that comes with the heaters is 18 AWG (for the fan) tied to 14 AWG (for the heating element), with 14 AWG exposed to connect to the main circuit. Additionally, every heater has a separate thermostat with 12 AWG wires. I cannot tell in the heater box what gauge the main wiring is, but it is definitely larger in diameter than the 14 AWG. As far as I understand, 30A breakers require 10 AWG wiring, so now I am confused as to how my house ever passed inspection and how I will pass for this remodel.
Am I missing something in the code that allows for appliances to have wiring connected to the 10 AWG of the circuit that is only 12 or 14 AWG? Is this safe?