TM 5-4610-223-12 Table 2-1.  Valves and Draincocks - Cont Startup Normal Symbol Location Function Type and size Position Operating position FV-18 Raw water level Controls water level 1 1/2 in. float valve Closed Closed alarm assem- in wet well. bly. DV-19 Upper drain line Partially drains erd- 2 in. gate valve. Closed Closed from bottom of lator tank for short erdlator. shutdown. DV-20 Lower drain line Drains erdlator tank 2 in. gate valve Closed Closed from bottom of completely. erdlator tank. DV-21 Drain line from Controls the amount of 1 in gate valve. Closed Partially concentrator sludge drawoff, drain open tank. concentrator. DV-22 Drain line from Drain concentrator 1 in. gate valve Closed Closed concentrator tank completely. tank. DV-23 Dram line from Drains waste tank 1 in. gate valve. Open waste tank SCV-24 Drain line from Prevents backward 2 in. horizontal swing Closed Closed wet well. flow of water into check valve wet well. DV-25 Drain water line Drains wet well. 2 in. gate valve Open Closed from wet well. DV-26 Drain line from Drain diatomaceous 3/4 in. gate valve. Closed Closed chemical slurry earth slurry feeder tank. compartment. DV-27 Drain line from Drains limestone 3/4 in gate valve. Closed Closed chemical slurry compartment. slurry feeder tank. CV-32 Filter water Control flow of filtered 1/2 in. gate valve. Closed Closed effluent line. water to slurry feeder tank diatomaceous earth compartment. CV-33 Slurry feeder Supplies filtered water 1/2 in angle globe Closed Open filtered water for mixing chemicals. valve. CV-34 Coagulated water Controls flow of 1 1/2 in. quick acting Closed Open line to suction coagulated water to gate valve. side of filter filter pump. water pump. SCV-35 Coagulated water Prevents backward 1 1/4 in. swing check Closed Open line from filter flow of water from valve. pump to in- filter. fluent plug valve. 2-3