Document 5b0Q7ownMR6yGnmDzOBLg6y60

American Society of Heating and Ventilating Engineers Guide, 1932 the use of check valves. In using this connection, the wet return connects through the shortest possible horizontal pipe 2 in. below the normal boiler water line into the pipe which joins the boiler outlet and boiler inlet on the boiler side of the stop valves. By this arrangement, if a careless operator should close the boiler outlet valve and should forget to close the boiler inlet valve, no water below the level of the inlet con- AOCEP1ABLE VETHOO PBEFEBED METHOD Fig. 8. Acceptable and Preferred Methods of Taking Branch from Main Fig. 9. Looping Main Around Beam REDUCING COUPLING, Fig. 10. Method of Dripping Main Where It Rises to Higher Level H ECCENTRIC SEDUCING (COUPLING. -Fig. 11. Method of Reducing Size of Main TO FWO LENGTHC - MULTIPLY A e* coustant for angle b. Fig. 12. Reducing Size of Main at Swing Connection Fig. 13. Constants for Determining Proper Length of Offset Pipe . nection to the loop could leave the boiler. It is of value only when the boilers are used in gravity circulating systems. Connections to Mains Fig. 8 shows two methods of taking off branches from mains on onepipe systems. They apply equally well, however, to other systems of up-feed piping. On one-pipe plants the branches are always made one pipe-size larger than the risers or the radiator connections which they serve. The method of carrying a main past an obstructing beam shown in Fig. 9 may be used advisedly with any system of piping. Fig. 10 shows a detail of piping at the end of a single-pipe main or at any point where it becomes desirable to rise for a fresh start at a higher level, the steam rising off the top of the main and the water draining 160 Chapter 9--Steam Heating Systems and Pipe Sizes dry RETURN-) DRY QETURN-f Fig. 15. Dripping Heel of Riser into Dry Return. (A Gate Valve is Recommended at the Inlet Side of the Trap) Fig. 14. Dripping Ends of Supply and Dry Return Mains. (Dry Return Too Small to be Vented) t-DRY RETURN REDUCING COUPLING. Fig. 18. Dripping End of Main into Wet Return OCT POCKET- Fig. 16. Dirt Pocket Connection COOLING LEG AT LEAST ^-5 -0' LONG HANOHOIE- Fig. 17. Looping Dry Return Main Around Opening <-DRY REHJDN Fig. 19. Dripping End of Main into Dry Return. (A Gate Valve is Recommended at the Inlet Side of the Trap) Fig. 21. Series of Lift Fittings Where Lift Is More Than 5 ft. 161