The problem is a unique one. If you install a 12 volt heater motor on a 12 volt system, there is NO resistor needed at full blast. But to get medium and low, THAT is a different story. To do that, you have to lower the voltage to 9.8 volts at Medium, and 6.2 volts at low. With a 12 volt system, two one ohm resistors ganged together will do exactly that. Problem is, we have the Power Formula to contend with. The Siemens 12 Volt replacement motor takes 3.94 amps at full speed. I tested that myself. Now I have one problem left to figure. What wattage resistors do I use? Research is still ongoing.
The power formula, wattage equals amperage times the voltage, seems easy. But I am stepping down so it would be the difference. Its a little confusing for this old brain.
