TM 10-6640-215-13 4-36.  REMOVE/REPLACE COMPONENTS OF AIR SYSTEM- continued. 3. Remove Flow Control Devices.  See figure 4-25. Remove laboratory stopcock valves by unscrewing valves from tees or elbows located in the air system mounted to laboratory walls. 4. Remove System Piping.  See figure 4-26. a. Remove sections of system piping by locating nearest pipe union and threaded pipe fittings. b. Disconnect union. c. Disconnect pipe nipple from elbow or coupling or valve. d. If damaged section of piping contains brazed joints or unions refer to direct support maintenance. INSTALLATION 1. Install Compressor.  See figure 4-23. a. Place compressor with its foundation in position on floor of machinery room.  Secure with flat washers, lockwashers, and capscrews. b. Connect drain tubing to tee fitting at compressor discharge. c. Connect discharge hose to tee fitting at compressor discharge. d. Electrically connect compressor motor to junction box and remove tags. e. Install junction box cover and fasten in place with two screws. 2. Install Air Tank.  See figure 4-24. a. Install air gage, air outlet valve, pressure switch and drain valve, tubing and fittings on air tank. b. Position  air  tank  in  place  on  foundation  in  machinery  room.    Secure  with  flat  washers,  lockwashers,  and capscrews. c. Connect drain line at bottom of air tank. 4-84