Document YDd5LJEojgwpKJXJDex22xqQn

Size o f Pipe American Society of Heating and Ventilating Engineers Guide, 1924-25 Theoretically, the pipe sizes calculated by this method will be so nearly correct that the friction loss and, therefore, the flow, will be equal at all' radiators. In practice, however, this is impossible because of the gaps in pipe sizes and many engineers specify the use of lock shield valves on one connection to each radiator so that the system may be adjusted to work evenly after it is in operation. 104 American Society of Heating and Ventilating Engineers Guide, 1924-25 A typical arrangement of pumps and heaters such as are used in forcedcirculation systems is shown in Fig. 41. GREENHOUSE HEATING BY HOT WATER Generally speaking greenhouses are heated by either hot water or steam systems though the former method is the older, simpler and more common method. Although the same tables, formulae or other data that are used to estimate the heating requirements of systems in the usual type of build ings are applicable to greenhouse heating systems, there are many dif ferences that must be kept in mind so that due allowance may be made in the specification of the plant. For instance, the highest temperatures are required at night, whereas with residence systems the maximum temperatures are required in the day time. Greenhouse fires are banked during the day and fuel consump tion is heaviest at night in contrast to practically all other types of buildings where the fires are banked at night. Greenhouse radiation is almost exclusively made up of piping. The temperatures demanded are almost always below 70 deg. and with lower temperatures and TABLE 75. TEMPERATURE REQUIRED FOR DIFFERENT PURPOSES House Temp. Required, 1 Deg. Fahr. General Purposes............................................................................................. 55 to 60 Cool .Greenhouse (Show)................................................................................ 45 " 60 Forcirtg House.--............................................................................................. 60 " 65 Tropical, or Stove H................ ...................................................................... 65 " 70 Conservatory (General Collection) (Winter Garden).............................. 60 " 65 Palm House.-....... ............................................................. -............................. 60 " 65 Tropical Palm House..........................-............................---......................... 65 " 70 Cool Palm House............................................................................................ 50 " 55 Orchid House......................................................................................... -......... 65 " 70 Cool Orchid House.......................................................... - -......-r................ 50 " 55 Rose House........................................................................i............................. 55 " 60 Carnation House............................................................................................. 45 " 55 Violet House..................................................................................................... 40 " 45 Propagating House.-...................................... :............................................... 55 " 60 Camelias and Azaleas.................................................................. .................. 45 " 50 Cool Vinery...................................................................................................... Cool and Damp Early Vinery (Start January and February)..... ....................................... 65. to 70 Second Vinery (Start February and March)....;........................................ 65 " 70 Late Vinery...................................................................................................... 65 " 70 Cool Peach House (Cold Damp Weather), Early Peach House (Start January and February)............................................................................. . 65 " 70 Second Peach House (Start February and March), Late Peach House ` (Ripen November and December)...............................-........ ................. 65 " 70 ' Tomato, and Cucumber House.......... ,........................ ............................ 65 "70 Lettuce House.............................................................................................. ... 40 " 45 M ushroom House................................ ........................ -.... ---...................... 55 "60 Fern House............................-.................. ................ .............-........... .......-- 60 ." 65 105