Document gDY7jg0bkz80O5z38RG69QZXa

Heating Ventilating Air Conditioning Guide 1952 Warm air (continued) mechanical heating syatema {continued) fans, 392t 463 filters, 392 furo&ce, 391 heavy duty. 392 selection, 463 humidification, 397 large systems, 453 " registers and grilles* 450 standard combinations, 451, 452 panel heating, 463 radiators, 370 Washer, washers,' 741 air. 1, 741 Water _ nnalvsis, 902 ata,pheric cooing equip- ment, 741, 751 characteristics, 902 classification, 903 coils. 761, 1027 . control temperature service, 1031 cooled condenser, 816 corrosion treatment, Wi demand, 1013 lauceta, 1014.1019 fittings, loss, 1018, 1019- fixtures, 1014 fixture units, 1014 formed deposits, 901 ' hecDal-fired, 1026 solar, 1033 Water teonlinved) heating, 896, 1026 load, 1023 make-up, 764 . maximum mam temperature, 744 meters, 1018,1019 mineralised, 902 properties of. 40 services, 1013 storage capacity. supply piping, 1013,1014,1W, 1030 arrangement, 1031 temperature control, ltwi thermodynamic properties ox, 40 treating chemicals, 901, 919 well temperatures, 746 Water vapor, 25, 32, 40,198 saturation pressure, 25, 40 specific enthalpy, 4 specific volume. J?'40,qq surface condensation, 199 Welding. 585 Window, windows , coefficients of transmission, 197 KdLtiou through, 256 ' ventilators, 570 WSrconditioning system, ?2 comfort zone,. 124 freezing equipment/ Wound rotor motor, SM Wrought-iron pipe, 585 Wrought-oteel pipe, 585 Year-round alf conditioning system, 629 contool methods, 631 Jmpn*nt arrangement, 630 instidlation, 630 location of apparatus, 642 selection, 640 Wet return. 8, 469 Wind, winds * due to stack eBect, 218 natural drfdtequiproent751 selection oi. velocity, 234, 26U Zone control, 630 zJme of evaporative regulation, 115 Zoning* 630 control. 630, 844 recoolmg, 631 reheat, 631 volume control, dm XXIV CHAPTER 1 TERMINOLOGY Glossary of Physical and Heating, Ventilating, Refrigerating and Air Conditioning Terms Used in the Text * Absolute Zero: The zero from which absolute temperature ib reckoned. Ap proximately --273.2 C or --459.8 F. Absorbent: A sorbent which changes physically or chemically, or both, during the sorption process. Absorption: The action of a material in extracting one or more substances present in an atmosphere or mixture of gases or liquids; accompanied by physical change, chemical change, or both, of the sorbent. Acceleration: The time rate of change of velocity, t.e., the derivative of velocity with respect to time. In the cgs system the unit of acceleration is the centimeter per (second) (second); in the fps system the unit is the foot per (second) (second), a = Acceleration Due to Gravity: The rate of gain in velocity of a freely falling body, the value of which varies with latitude and elevation. The international gravity standard has the value of 980.665 cm per (sec) (sec) or 32.174 ft per (sec) (sec) which is the actual value of this acceleration at sea level and about 45 deg latitude. Adiabatic: An adjective descriptive of a process such that no heat is added to, or taken from, a substance or system undergoing the process. Adsorbent: A sorbent which does not change physically or chemically during the sorption process. Adsorption: The action, associated with surface adherence, of a material in ex tracting one or more substances present in an atmosphere or mixture of gases and liquids, unaccompanied by physical or chemical change. Commercial adsorbent materials have enormous internal surfaces. Aerosol: An assemblage of small particles, solid or liquid, suspended in air. The diameters of the particles may vary from 100 microns down to 0.01 micron or less, e.g., dust, fog, smoke. Air Cleaner: A device designed for the purpose of removing airborne impurities such as dusts; gases, vapors, fumes and smokes. (Air cleaners include air washers, air filters, electrostatic precipitators and charcoal filters.) Air Conditioning: The simultaneous control of all, or at least the first three, of those factors affecting both the physical and chemical conditions of the atmosphere within any structure. These factors include temperature, humidity, motion, distri bution, dust, bacteria, odors and toxic gases, most of which affect in greater or lesser degree human health or comfort. (See Comfort Air Conditioning.) Air, Dry: In psychrometry, air unmixed with, or containing no, water vapor. Air, Saturated:. A mixture of dry air and saturated water vapor, all at the same dry-bulb temperature. Air, Standard: Air with a density of 0.075 lb per cu ft and an absolute viscosity of 1.22 X IQ"6 lb mass per (ft) (sec). This is substantially equivalent to dry air at 70 F and 29.92 in. (Hg) barometer. Air Washer: An enclosure in which air is drawn or forced through a spray of water in order to cleanse, humidify, or dehumidify the air. Anemometer: An instrument for measuring the velocity of a fluid. Aspect Ratio: In air distribution outlets, the ratio of the length of the core of a grille, face or register to the width. In rectangular ducts, the ratio of the width to the depth. Atmospheric Pressure: The pressure due to the weight of the atmosphere. It is the pressure indicated by a barometer. Standard Atmospheric Pressure or Standard Atmosphere is the pressure of 76 cm of mercury having a density of 13.5951 grams per under standard gravity of 980.665 cm per (sec) (sec). It iB equivalent to 14.696 lb psi or 29.921 in. of mercury at 32 F. Baffle: A surface used for deflecting fluids, usually in the form of a plate or wall. 1