The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"

 Guys, these power supplies are also voltage adjustable, from 9 to 14.8 volts! Maybe, just maybe, we can lower the pumps voltage, to slow its flow down a bit, or maybe increase voltage to 14.8 vdc, to get the last bit of distance out of the pumps ? I have not tried this, and the pumps may overheat or burn up at higher or lower sustained voltages ? Just thought I would throw this out there, in case anyone wants to play.

There are advantages/disadvantages to running a 12 volt roof cleaning pump this way, vs just using a battery.
One of them is the added "need" for a Generator, but that isn't an absolute need, since you can simply plug your 12 volt power supply in at your customers house.
Plus, when you use one of these 12 volt power supplies, you have 30 amps all day long, and all of the time!
Not so with a Battery, because as the battery gets it's charge drained, it looses it's amperage, and the 12 volt pump begins to suck, as far as performance goes.
I have cleaned many roofs in a day with 12 volt pumps powered by batteries, and sometimes I noted a loss of pump performance on the last few roofs, compared to when the battery was freshly charged.