Document yk3N85z2KyVOpnN05zQdrVkXr

552 CHAPTER 25 / . 1950 Guide condensate !from the cooling coil is sprayed over the condenser: surface and-vaporized, thus eliminating the need for drain connections. A simple dampering arrangement is generally provided for exhausting some air from the room, in addition to introducing outside air and recirculating required amounts of air. It is possible to remove the equipment for winter storage or utilize the ventilating features for winter operation. Controls for Room Cooling Units '/Control devices provided for self-contained cooling units generally will include' all necessary means for automatic operation. Provision is also made'for adding auxiliary external controls, when desired. - Remote units are not generally equipped with controls. Control systems for remote units, and auxiliary controls, for self-contained units, are covered in the general treatment of Controls in Chapter 38. Fio. 7. Self-Contained Aik-Cooled Unit Aik Conditioner RATINGS OF UNIT AIR CONDITIONERS There are two codes governing the rating and testing of unit air con ditioners. The first code; Standard Method'of Rating: and Testing Air Conditioning Equipment;1 covers all types of air conditioning units except the self-contained-type.: The latter is covered by the-second code', The Standard-Method of Rating and Testing Self-Contained Air Conditioning Units fOr' Comfort' Codling.2 The two codes are necessary- because of the 1 basic difference caused: by the heat given up. by the self-contained-units. The.'standard rating conditions for self-contained- unit air conditionere, as given in'the code; are set forth in Table 1.: f ' .. - ... The standard rating of,a self-contained unit for the conditions specified m'Tdbie, 1, includes all items which apply to the function'of a unit'as: J[l);name;'of,.unit, (2) functions which unit performs, (3) .data.on-cooling, ' (4) data on heating, (5) data on air flow; and (6) data on humidification. -./ The standard:rating conditions for unit air conditioners,.other th^n the . selfr-contained type, are identical with those, in Table 1, except that entering wet-bulb .temperature for: cooling is expressed as 50 per cent relative /humidity,,(66.7. F ,wet-bulb) instead of 67 F wet-bulb temperature. In Unit. Air;Conditioners and Unit Air Coolers /,553-. addition, the. saturated; suction -refrigerant., temperature for comfort-, cooling-is specified at 40 F. This condition, is omitted from Table,1 for, self-contained units because it is immaterial in the:rating of a unit that in cludes the evaporator and condensing unit. _. . Table X. Standard Rating Basis fob Self-Contained.Air Conditioning-Units Functions Types op Units Item Description . - Value All Cooling All - - a- - ` Barometric Pressure ; 29.92 in. Hg. Water-Cooled, Air-Cooled and Evaporatively-Cooled Condensers b. Unit Ambient, and'Air. Entering Room--Air Inlet (1): Dry-Bulb.-/:. (2) Wet-Bulb c ' Ventilation Air - 80 F 67 F See-Note Water-Cooled Condensers d Water Temperature Entering Unit e;. Water Temperature Leaving' Unit' 75 F 95 F .1 Air-Cooled f Air Entering Outside Air Inlet and Evapora- (1) Dry-Bulb tively-Cooled (2) Wet-Bulb : Condensers 95 F . . 75 F Heating E Unit Ambient and Total Air Enter-- ing Unit 70 F All Types Provided h Heating Medium, Pressure or ` with Heating Temperature: Function (1) Dry Saturated Steam 16.7 lb per sq in. abs (2) Water In .. 180 F (3) Water Out 160 F All Types i Unit Ambient ^ Provided with Humidifying Humidifying i Total Air Entering Unit - Function (1) Dry-Bulb (2) Wet-Bulb 70 F . 70 F. 53 F Air Circulation All k Filters New and Clean Note: Rating shall be baaed on both ventilation and recirculated room air entering at 80 F dry-bulb: and 67 F wet-bulb temperature. (The Note as given in the code haa been'condensed in order to remove ma-, terialnot pertinent tothia chapter). . , APPLICATION OF UNTTARlf EQUIPMENT One of the chief advantages resulting from use of factory produced units is the saying in installation and field assembly labor, a factor that/ should always be kept in mind when selecting .a location for these units. Because of their compactness, the tendency exists to put them in closets, storage rooms, and other inaccessible places, where installation is so difficult that much of this cost advantage is lost. ;. Access panels are provided on units , for the proper servicing'and main-' tenahce of;'the'.equipment.. Adequate puitside clearance at these panels is^