There are two blowers that address cabin heat.

A plans blower moves heat across the exhaust muff and pulls it forward. That is done with a marine sump blower, drawing a max of 1.2a and fused at 5 amps. The harness appears to be equivalent to 24 awg. I will follow the FAA rules on load, distance and allowable drop. I will install a heat duct from the engine compartment forward to the passenger footwell, with the motor forward of the passenger rudder controls.

A defrost / avionics fan pushes air across the radio stack and then washes the front of the canopy. This is a 6 amp rotary fan The two work well together, able to spin the motor at all settings and drawing 6v at the half-way setting and full battery voltage at the "max" setting. The manufacturer wired the fan with 24 AWG; my wiring will be to-from the IP connect points, fused at 7.5 amps, wire as per the FAA rules.

I also picked up a nice 10 amp pulse width modulation rotary switch. It is ideal for these motors, but I'm not sure it makes sense. When you want heat or defrost, you want it full on. Is there a use for the switch?