A little more information for you. The air governor does few things along with its job of regulating the air pressure. When the pressure get to the set point, it stop (unloads)the air compressor. I am use to heavy equipment so, I am guessing the RV's system would be the same way. To unload the compress air is used to open the compressor valves(Unloading valves) so it will not pump air under pressure. At this time the air governor will also send air under pressure to the air drier to open the dump valve to let the air drier dump out any moist air from it tank. The Air drier Check valve will keep the air in the air tank up to pressure for a good length on time is your air system is tight. As your system air pressure drop to the triggering point, the air governor will release the Air compressor unloading valve and the air drier dump valve. At this point the compressor will start to fill your air system back up. Gary
