An auto drain valve 100 comprises a valve body 222 wherein a piston 111 having a piston rod 08 with sealing disk 07 and sealing member 03 which is movable within said valve body 222 wherein air vent 30 and liquid outlet 40 and closes simultaneously. Further the valve body 222 is connected to the bowl 10; valve body 222 consisting of air vent 30, liquid inlet 40′ and liquid outlet 40; moveable piston 111, solenoid coil 9 surrounding the piston rod 08; spring 01 and spring 02 resiliently biasing on the Piston 111 seal air vent 30 and liquid outlet 40 in its de-energized condition; when the solenoid coil 09 is energized and Piston 111 moves away from air vent 30 and liquid outlet 40 simultaneously, liquid is drained form bowl 10 through liquid inlet 40′ into valve body 222 and drained out form liquid outlet 40.

An auto drain valve 100 comprises a valve body 222 wherein a piston 111 having a piston rod 08 with sealing disk 07 and sealing member 03 which is movable within said valve body 222 wherein air vent 30 and liquid outlet 40 and closes simultaneously. Further the valve body 222 is connected to the bowl 10; valve body 222 consisting of air vent 30, liquid inlet 40′ and liquid outlet 40; moveable piston 111, solenoid coil 9 surrounding the piston rod 08; spring 01 and spring 02 resiliently biasing on the Piston 111 seal air vent 30 and liquid outlet 40 in its de-energized condition; when the solenoid coil 09 is energized and Piston 111 moves away from air vent 30 and liquid outlet 40 simultaneously, liquid is drained form bowl 10 through liquid inlet 40′ into valve body 222 and drained out form liquid outlet 40.

An air compressor assembly for filling self-contained breathing apparatus air containers has at least one condensate separator. The condensate separator includes a liquid-retaining vessel a liquid-level sensor. A drain valve is in fluid communication with the condensate separator. The drain valve is configured to open and drain retained liquid from the liquid-retaining vessel when the liquid-level sensor detects that a level of the retained liquid reaches a drain valve activation triggering level.

An air compressor assembly for filling self-contained breathing apparatus air containers has at least one condensate separator. The condensate separator includes a liquid-retaining vessel a liquid-level sensor. A drain valve is in fluid communication with the condensate separator. The drain valve is configured to open and drain retained liquid from the liquid-retaining vessel when the liquid-level sensor detects that a level of the retained liquid reaches a drain valve activation triggering level.