Basically it is just to maintain level as initial leveling should be done with the engine running.
Could be, it can put out 125 psi, but not much volume.
There isn't much to check or adjust. With the system on (red light showing) have someone push a raise button while you watch and listen, it should come on. When in auto level if a yellow light comes on the compressor should come on, if the system can not level by releasing air first. After 30 min if level is not achieved the pump should stop and will not run again until a new leveling sequence is initiated.
Not sure if we have the same system as we have different models. Barry Beam has a HWH manual posted on his website.
http://www.beamalarm.com/foretravel-links/PDF/hwh-manual-ml31043.pdf (http://www.beamalarm.com/foretravel-links/PDF/hwh-manual-ml31043.pdf)