How to run a 12 volt roof cleaning pump w/o a battery! in Non Pressure Roof Cleaning Equipment Posted May 19, 2016 · Report reply How is the 12v power supply tests turning out for ya MID-MO. Very curious as I'm putting together a system as soon as everything shows up. On paper it sounds brilliant and I'm hoping for positive feedback but as far as I'm aware you are the only one doing field trials. Anxious to hear your results.