The only real issue for DIY shop is it 3ph, it’s 90 psi, weighs a ton..........other than that it would make a great shop for DIY guy. Crank the pressure to 150 ..........change the motors and it’s ready to work!!!!!
I disagree; those single-cylinder pumps are tiny. This is very similar to the duplex air compressors used on pneumatic-control HVAC systems - they are low-flow, low-pressure, high-reliability compressors designed to run for decades with minimal maintenance.
So you crank up the pressure and change the motors to spin them a bit faster - you still only have 6-7cfm @ 125psi when you are done. That's a joke for a real shop compressor.
Skip this compressor, even for free.
For those of you who don't know, this compressor is for dry-pipe fire sprinkler systems. What is that, you ask? Well let's say that you have an unheated area that you want to put fire sprinklers in, and you don't want to heat-trace the wet-pipe system. You install a dry-pipe system in the area that you want to protect. The dry-pipe system uses compressed air inside of it so there is no water to freeze.
The temperature-sensitive capsules at the heads operate in exactly the same way as they do in a wet-pipe system - they break and allow flow. Then there is a flow-sensing valve that turns on a water valve (located in a heated portion of the building) which floods the dry piping with water and then it operates just like a wet pipe system does.
It's more expensive but this system can be used outdoors, say underneath the overhang of a building, over a loading dock, in an engine generator room that could possibly freeze in the winter when the generator runs, and so on.