Think common goes to the humidifier and hot wire goes to the control. Per aprilaire for 4655 manual control it doesn't matter which of the two wires coming out of the humidifier or the control 2 screws. It's just completing a circuit
No, I installed it on the supply. I didn't focus on the installation as much since there's many other videos out there on that. I could not find a video on how it can be wired without the 24 volt block that comes with it.. and how it can be wired in the heat switch or the fan switch.
@@ranmelk I used cold but hot would be just as good or better. I'm in Ohio USA. If you have a lot of 25 F to 0 F degrees you should have one. If you're mostly 35 F to 60 F probably not.