All compressors do not have ASME certification. Only ASME certified compressors can be sold in some states. This valve will have a pull ring attached to it to allow you to check the valve to make certain the valve is not clogged or corroded. An oil level sight glass, a tank pressure gauge and, of course, a pressure regulator and gauge are important, as each tool and job has a specific pressure requirement. The tank maintains air at maximum pressure from 100 to 125 pounds of pressure per square inch.
PSI is the force of the pressurized air delivered to the tool.
Projects and tools have both pressure and volume requirements. A manual thermal overload button is important in case of overloads or if the motor overheats. If the motor overheats, it automatically shuts off. This protective control button must be pushed for the compressor to run once the motor has cooled down, preventing a sudden and unexpected restart. The best air intake filtration system will be enclosed and mounted on the side of the compressor.