TM 10-6640-238-13 5-2 Section II.  DIRECT SUPPORT MAINTENANCE PROCEDURES Alphabetical Index Maintenance Title Paragraph Air/Steam Flow Rate Indicator Meters ............................................................................................................. 5-20 Boiler Low Water Cutoff Pump Control........................................................................................................... 5-14 Boiler Low Water Pump ................................................................................................................................... 5-15 Electric Steam Boiler ........................................................................................................................................ 5-16 Environmental Control Unit.............................................................................................................................. 5-25 Flow Control Devices (Gum Bath System)....................................................................................................... 5-17 Flow Control Devices (Water System) ............................................................................................................. 5-9 Freezer (Ice Cube Maker) ................................................................................................................................. 5-22 Gum Bath Vent/Fume Vent Blower and Motor ................................................................................................ 5-21 Gum Content Test Bath..................................................................................................................................... 5-13 High Pressure Steam Boiler .............................................................................................................................. 5-18 Hot Water Heater Distribution Box................................................................................................................... 5-23 Introduction....................................................................................................................................................... 5-4 Pyrometer Fuse Box.......................................................................................................................................... 5-24 Pyrometer Indicator/Control ............................................................................................................................. 5-19 Sump Pump ....................................................................................................................................................... 5-12 Surge Tank ........................................................................................................................................................ 5-7 Water Chiller..................................................................................................................................................... 5-8 Water Heater ..................................................................................................................................................... 5-11 Water Pump....................................................................................................................................................... 5-5 Water Tank........................................................................................................................................................ 5-6 Water System System Piping (Typical) ............................................................................................................ 5-10 5-4. INTRODUCTION. a. This section contains instructions covering maintenance functions for direct support level maintenance on the Petroleum Laboratory.  Personnel required are listed only if the task requires more than one. b. After completing each maintenance procedure, perform operational check to be sure that equipment is properly functioning.