Air conditioning - Wikipedia, the free encyclopedia. For other uses, see AC. RRRE-05043-1Q Page 1 of 3 Intertek, ETL Semko 1717 Arlingate Lane Columbus, OH 43228 REFRIGERANT RECOVERY/RECYCLING EQUIPMENT CERTIFICATION PROGRAM Program of the Air-Conditioning & Refrigeration Institute TEST REPORT REPORT S.In common use, an air conditioner is a device that removes heat from the air inside a building or vehicle, thus lowering the air temperature. The cooling is typically achieved through a refrigeration cycle, but sometimes evaporation or free cooling is used. Air conditioning systems can also be made based on desiccants. However, in construction, such a complete system of heating, ventilation, and air conditioning is referred to as heating, ventilation, and air conditioning (HVAC . The business of harvesting ice during winter and storing for use in summer became popular towards the late 1. The evaporation of water cooled the air blowing through the window. This process also made the air more humid, which can be beneficial in a dry desert climate. In Ancient Rome, water from aqueducts was circulated through the walls of certain houses to cool them. Other techniques in medieval Persia involved the use of cisterns and wind towers to cool buildings during the hot season. During the subsequent Song Dynasty (9. The introduction of residential air conditioning in the 1. Sun Belt in the United States. In 1. 75. 8, Benjamin Franklin and John Hadley, a chemistry professor at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin and Hadley confirmed that evaporation of highly volatile liquids (such as alcohol and ether) could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to speed- up the evaporation. They lowered the temperature of the thermometer bulb down to . Franklin noted that, soon after they passed the freezing point of water 0 . In 1. 84. 2, Florida physician John Gorrie used compressor technology to create ice, which he used to cool air for his patients in his hospital in Apalachicola, Florida. He hoped to eventually use his ice- making machine to regulate the temperature of buildings. He even envisioned centralized air conditioning that could cool entire cities. Though his prototype leaked and performed irregularly, Gorrie was granted a patent in 1. Improved process for the artificial production of ice. His hopes for its success vanished soon afterwards when his chief financial backer died; Gorrie did not get the money he needed to develop the machine. According to his biographer, Vivian M. Refrigerant Pressure Enthalpy. Download32 is source for refrigerant pressure enthalpy shareware, freeware download - PT Chart, PT Charts - HVAC Cheat Sheet, ClimeCalc, My Blood Pressure, UTS Blood Pressure for Palm OS, etc. This R134a refigerant calculator determines the gas pressure based on temperature of R134a refrigerant. Includes a Pressure Temperature Chart. Simply enter the cycle parameters and select a refrigerant. The program allows you to compare the simple 1-stage and 2-stage cycles. The following is a list of refrigerants with their Type/Prefix. Refrigerant Concentration Limit / Immediately Dangerous to Life or Health in parts per million. T y p e ASHRAE Number IUPAC Chemical Name Molecular Formula CAS. EPA-Approved Section 609 Program. ASE Customer Service at 1-800-390-6789 from 8 a.m. Sherlock, he blamed the . Gorrie died impoverished in 1. James Harrison's first mechanical ice- making machine began operation in 1. Barwon River at Rocky Point in Geelong (Australia). His first commercial ice- making machine followed in 1. This novel system used a compressor to force the refrigeration gas to pass through a condenser, where it cooled down and liquefied. The liquefied gas then circulated through the refrigeration coils and vaporized again, cooling down the surrounding system. The machine employed a flywheel and produced 3,0. Though Harrison had commercial success establishing a second ice company back in Sydney in 1. American advantage of unrefrigerated beef sales to the United Kingdom. His choice of a cold room system instead of installing a refrigeration system upon the ship itself proved disastrous when the ice was consumed faster than expected. Electromechanical cooling. After graduating from Cornell University, Carrier found a job at the Buffalo Forge Company. While there, he began experimenting with air conditioning as a way to solve an application problem for the Sackett- Wilhelms Lithographing and Publishing Company in Brooklyn, New York. The first air conditioner, designed and built in Buffalo by Carrier, began working on 1. July 1. 90. 2. Designed to improve manufacturing process control in a printing plant, Carrier's invention controlled not only temperature but also humidity. Carrier used his knowledge of the heating of objects with steam and reversed the process. Instead of sending air through hot coils, he sent it through cold coils (filled with cold water). The air was cooled, and thereby the amount of moisture in the air could be controlled, which in turn made the humidity in the room controllable. The controlled temperature and humidity helped maintain consistent paper dimensions and ink alignment. Later, Carrier's technology was applied to increase productivity in the workplace, and The Carrier Air Conditioning Company of America was formed to meet rising demand. Over time, air conditioning came to be used to improve comfort in homes and automobiles as well. Residential sales expanded dramatically in the 1. In 1. 90. 6, Stuart W. Cramer of Charlotte, North Carolina was exploring ways to add moisture to the air in his textile mill. Cramer coined the term . He combined moisture with ventilation to . Willis Carrier adopted the term and incorporated it into the name of his company. Pierre Du. Bose (1. Meadowmont, all disguised behind intricate and attractive Georgian- style open moldings. The name is a trademark name owned by Du. Pont for any chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), or hydrofluorocarbon (HFC) refrigerant. The refrigerant names include a number indicating the molecular composition (e. R- 1. 1, R- 1. 2, R- 2. R- 1. 34. A). The blend most used in direct- expansion home and building comfort cooling is an HCFC known as chlorodifluoromethane (R- 2. Dichlorodifluoromethane (R- 1. US until 1. 99. 4, when most designs changed to R- 1. A due to the ozone- depleting potential of R- 1. R- 1. 1 and R- 1. US for this type of application, so the only source for air- conditioning repair purposes is the cleaned and purified gas recovered from other air conditioner systems. Several non- ozone- depleting refrigerants have been developed as alternatives, including R- 4. A. It was first commercially used by Carrier Corp. These include HCFCs (R- 2. U. S. HCFCs, in turn, are supposed to have been in the process of being phased out under the Montreal Protocol and replaced by HFCs such as R- 4. A, which lack chlorine. Moreover, policy and political influence by corporate executives resisted change. The environmental organization Greenpeace solicited a European laboratory to research an alternative ozone- and climate- safe refrigerant in 1. E. P. A., disparaging the approach as . Notice frost formation. In the refrigeration cycle, heat is transported from a colder location to a hotter area. As heat would naturally flow in the opposite direction, work is required to achieve this. A refrigerator is an example of such a system, as it transports the heat out of the interior and into its environment. The refrigerant is used as the medium which absorbs and removes heat from the space to be cooled and subsequently rejects that heat elsewhere. Circulating refrigerant vapor enters the compressor, where its pressure and temperature are increased. The hot, compressed refrigerant vapor is now at a temperature and pressure at which it can be condensed and is routed through a condenser. Here it is cooled by air flowing across the condenser coils and condensed into a liquid. Thus, the circulating refrigerant removes heat from the system and the heat is carried away by the air. The removal of this heat can be greatly augmented by pouring water over the condenser coils, making it much cooler when it hits the expansion valve. The condensed, pressurized, and still usually somewhat hot liquid refrigerant is next routed through an expansion valve (often nothing more than a pinhole in the system's copper tubing) where it undergoes an abrupt reduction in pressure. That pressure reduction results in flash evaporation of a part of the liquid refrigerant, greatly lowering its temperature. The cold refrigerant is then routed through the evaporator. A fan blows the interior warm air (which is to be cooled) across the evaporator, causing the liquid part of the cold refrigerant mixture to evaporate as well, further lowering the temperature. The warm air is therefore cooled and is pumped by an exhaust fan/ blower into the room. To complete the refrigeration cycle, the refrigerant vapor is routed back into the compressor. In order for the process to have any efficiency, the cooling/ evaporative portion of the system must be separated by some kind of physical barrier from the heating/ condensing portion, and each portion must have its own fan to circulate its own . Modern air conditioning systems are not designed to draw air into the room from the outside, they only recirculate the increasingly cool air on the inside. Because this inside air always has some amount of moisture suspended in it, the cooling portion of the process always causes ambient warm water vapor to condense on the cooling coils and to drip from them down onto a catch tray at the bottom of the unit from which it must then be routed outside, usually through a drain hole. As this moisture has no dissolved minerals in it, it never causes mineral buildup on the coils, though if the unit is set at its strongest cooling setting and happens to have inadequate circulation of air through the coils and also experiences a failure of the thermistor which senses the ambient temperature in the room, the coil's fins can develop a layer of ice which will then grow and eventually block the circulation of air on the cool side of the unit altogether in a positive feedback loop that will cause the formation of an ice block inside the unit: only minuscule amounts of cool air will then manage to come from the exhaust vent until this ice is removed or is allowed to melt. This will happen even if the ambient humidity level is low: once ice begins to form on the evaporative fins, it will reduce circulation efficiency and cause the development of more ice, etc. A clean and strong circulatory fan can help prevent this, as will raising the target cool temperature of the unit's thermostat to a point that the compressor is allowed to turn off occasionally.
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