TM 10-6640-215-13 5-12.  REMOVE/INSTALL WATER HEATER. This task consists of: a.  Removal   b.  Installation INITIAL SET-UP: Tools required General Mechanics Tool Kit, (Appendix B, Section III, Item 2) Material required Teflon Tape, (Appendix E, Section II, Item 157) Lockwashers, (Appendix F) Personnel Required Two (2) General Safety Instructions WARNING ELECTRICAL SHIOCK Before  performing  any  maintenance  actions  on  electrical  equipment,  ensure  all  electrical  power has been turned off.  Death or serious injury may occur from failure to do this. REMOVAL Remove Water Heater.  See figure 5-8. a. On MAIN POWER PANEL set water heater circuit breaker AICB17 to OFF. b. Remove shelf from cabinet L' to gain access to water heater. c. Turn off water pump and open water heater drain valve located in cabinet U.  Open hot water faucet to aid drainage. d. Disconnect water inlet union from water heater. e. Disconnect water outlet union from water heater. f. Disconnect relief valve union from water heater. g. At junction box in cabinet U, tag for reconnection and disconnect water heater wiring and conduit. h. Remove two screws and lockwashers from each of the four mounting supports for water heater. i. Remove defective water heater from cabinet U. j. Remove relief valve and two threaded pipe adapters from water heater.  Retain for reuse. k. Tag for reconnection and disconnect wiring and conduit from water heater. 5-14