TM 10-6640-239-13 5-18 5-11.    WATER HEATER. This task consists of: a.   Remove b.   Install INITIAL SET-UP Tools Required General Mechanics Tool Kit, (Appendix B, Section III, Item 1) Materials/Parts Required Teflon Tape, (Appendix E, Section II, Item 139) Lockwashers, (2) Personnel Required Two (2) Equipment Condition Grease Working Machine Removed (Paragraph 4-69) Water Bath Removed (Paragraph 4-69) Sulfur Apparatus Removed (Paragraph 4-69) General Safety Instructions WARNING ELECTRICAL SHOCK Before performing any  maintenance actions on electrical equipment, ensure  all electrical power has been turned off.  Failure to comply with this warning may result in serious injury or death. REMOVE Remove Water Heater.  See Figure 5-7. a. On Main Power Panel set water heater circuit breaker A1CB17 to OFF. b. Remove shelf from cabinet U to gain access to water heater (1). c. Turn off water pump and open water heater drain valve (2).  Open hot water faucet to aid drainage. d. Disconnect water inlet union (3) from water heater (1). e. Disconnect water outlet union (4) from water heater (1). f. Disconnect relief valve union (5) from water heater (1). g. At junction box (6) in cabinet U, tag and disconnect water heater wiring and conduit (7). h. Remove two screws (8) and lockwashers (9) from each of the four mounting supports (10) for water heater (1). Discard lockwashers. i. Remove water heater (1) from cabinet U. j. Remove relief valve (11) and two threaded pipe adapters (12) from water heater (1).  Retain for reuse. k. Tag and disconnect wiring and conduit (7) from water heater (1).