Air Conditioner And The Refrigeration System History Essay

Why does your mouth water when you see an ice-cream? How can you shop and still be cool? Why are long drives not annoying? Why watching movies in multiplexes so comfortable? How can you beat the heat in summer? The answers to all these questions have one thing in common. Yes, you guessed it right. It is an AIR CONDITIONER AND THE REFRIGERATION SYSTEM. But was the invention made just to suffice the needs of comforts and luxury of human beings???

On a second thought, how to increase the shelf life of perishable products? How to deliver and store good food……..6000 miles from home? What facilitates production of life saving drugs? There are many such questions and the answer is yet the same, it is an air conditioner and the refrigeration system. These are machines which not only provide material comforts but also improve the quality of the living conditions of the people and the sources on which we are dependent.

The credit goes to Willis Haviland Carrier, the father of modern refrigeration and air conditioning system. But what idea sparked in Willis Carrier’s mind? What inspired him to make such a unique discovery? Was the invention just an accident or was it made in the process of solving certain mechanical problem? Let us recall the stages in his lifecycle which gave the world a celebrity whose discovery has been compared to other inventors like Thomas Alva Edison and the Wright Brothers. Each episode of his life and career presents the picture of ‘Carrier’ as a man rich personality, a genius and a leader.

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The FAMILY:

Duane Carrier and his wife Elizabeth Carrier became proud parents of a bonny baby boy, Willis Carrier on November 26, 1876 in Angola, New York. Duane Carrier initially began his career as a music teacher and taught music to Indians. He also ran a small grocery store and for some time worked as a postmaster. He finally settled himself as an ordinary farmer and along with Elizabeth lived a life of simplicity in their farmland in the western part of New York State. The birth of their only child brought lots of happiness and contentment in their lives. Elizabeth’s forefathers were natives of New England in the 17th Century and she was a ‘Quaker’ by birth who was the first in the family to marry outside her caste.

Duane Carrier would spend a lot of time on his farm and it was Elizabeth who would manage the household chores all by herself. As time flew by young Willis would happily play mechanics oriented games and enjoyed assembling and fixing them. Perhaps his inventive and mechanical skills were inherited from his mother as it was Elizabeth who fixed and repaired family clocks, sewing machines and other household machines. Little did Elizabeth know that her son would one day be an engineer and would create history in the world of mechanical engineering.

A LESSON for Life:

Young Willis was enrolled in Angola Academy, a one room school where he received his primary education. He was intelligent and studious but at the age of nine, he had trouble grasping the concept of fractions and it was his mother who found a very innovative way to overcome his fear of solving it. She instructed him to go to the cellar and bring up a pan of apples. She then asked him to cut the apples in halves, quarters and eights and add and subtract the parts. Carrier recalls the episode very fondly and said, “She opened up a new world to me and gave me a pattern for solving problems that I have followed ever since.” In one-half hour, he said, “she educated me. Fractions took a new meaning and I was very proud. No problems would be hard for me after that. I would simply break them into something simple and then would be easy to solve”. Elizabeth took keen interest in Willis academic pursuits and taught him fractions and other mathematical problems that captured his interest and eventually inspired him to become an Engineer.

Willis was a serious and a hardworking student who toiled in the day at his father’s farm and often burned the midnight oil solving math problems. One day during a snowstorm he was so engrossed working on the geometry problems outside his home that he forgot the weather around him. Such was his dedication.

At the age of eleven Willis lost his mother whom he considered as his mentor and his idol and he vowed to follow the path which she showed. Willis also attributed his talents in mathematics and mechanics to inheritance from his mother.

ROBUST ALL-ROUNDER:

Taking into consideration his intelligence, Willis was asked by his school authorities to teach other students before entering Central High School in Buffalo, New York where he completed his secondary education. He then won a state scholarship and got admission in Cornell University to study mechanical engineering.

Willis was 6 feet 6 inches tall, athletic and possessed a robust personality. He was an all-rounder as he actively participated in swimming, skating, boxing and other sports events organized by his college. He worked hard and earned his way through college on scholarships, teachings, doing other odd jobs like mowing lawns, distributing milk, and working as an agent for a boarding house and so on. He and some of his friends got together and began a laundry agency, a first of its kind in the United States.

The main motive behind all this was the need to be financially independent. He would often recall his mother’s advice “FIGURE OUT THINGS YOURSELF”

His handsome personality attracted Edith Claire Seymour, a Cornwell student and the two fell in love. After his graduation in Mechanical Engineering in 1901, they decided to unite forever and in the subsequent year they were happily married.

The FIRST STEP on his PATH:

Soon after completing his graduation, Willis was offered a job as an Engineer with the Buffalo Forge Company in Buffalo, New York. The Company was engaged in heating, drying and forced draft system. Willis was obsessed with mechanical engineering and accepted the job offer. He was determined to put mechanical engineering on a more rational basis than what was practiced at that time. In those days engineers did not really understand the way the machinery functioned and hence created huge and large factors of safety into their designs which led to inefficiencies.

Willis took this as a challenge and decided to probe further the functioning of the Company’s products. At the end of just 6 months he submitted a paper titled “Mechanical Draft” at the Company Annual General Meeting. His thesis was theoretical but on a very practical subject and although it was delivered by a newcomer, it impressed everybody. The Company realized that Willis possessed mechanical talents and needed a platform to explore it further. They decided to provide him all the necessary technical and theoretical support and also allowed him to pursue his interest during and after normal working hours. Willis established the world’s first Research and Development laboratory, in the HVAC (Heating, Ventilation, Air Conditioning) industry at the Buffalo Forge Company. He was just 25 years old.

During his course of research, Willis discovered that except for physical and thermal properties of steam and air, there was no other data available. He regularly carried tests and experiments in the lab and derived equations to complete the calculations.

FIRST BREAKTHROUGH:

Willis first major job as a young engineer was to develop an air conditioning system for Sackett Wilhelm Lithographing Company situated in Brooklyn, New York. The challenge faced by the Company’s engineers was not heat but the humidity. The then consulting Engineer Walter Timmis visited the Manhattan Office of J. Irvine Lyle, the head of the Buffalo Forge’s sales team in New York to take stock of the situation.

The paper in their printing plant would expand or contract depending on the amount of water absorbed from the air. It was one size on a hot humid day and different on a hot dry day. Printing in color faced the same problem as colors overlapped or failed to match those printed on the previous day.

The printers had a tough time as they often had to reprint jobs or reduce the speed of their presses to match the quality. Times had a rough idea about how to solve the problem but he needed help and guidance. He approached Lyle who was very impressed with the Cornwell Graduate-Willis Carrier of the Buffalo Forge Company. He directed Timmis to Willis Carrier and the first step in a long and prosperous collaboration began.

How did Willis Carrier overcome this genuine problem?? To our surprise the solution to resolve this problem gave birth to the concept of designing an air conditioned system.

The INFANT STAGES of Cooling:

Carrier readily accepted the challenge and immediately began working on the problem. He and Timmis joined together and conducted certain experiments and test with a rolled towel woven in a burlap and saturated with a solution of calcium chlorine brine. Though the apparatus succeeded in removing heat it added salt and odor to the air which was not acceptable in the printing procedure.

Carrier then tried his own experiment by replacing steam with cold water flowing through heating coils and balancing the temperature of the coil surface with the rate of air flow and so on. Carrier worked hard to resolve the issue and converted data obtained from tests and experiments into equations, tables and graphs. He successfully charted the flow rate and temperature of chilled water and the flow rate through the coil needed to cool and dehumidify each cube foot of air to a specified temperature and humidity.

The first set of coils was installed along with fans, ducts, heaters, perforated steam pipes for the humidification process. Cooling water was drawn from an artesian well. Artesian well is a well in which pressurized water naturally rises to the surface. It is then supplemented by an ammonia compressor to meet the demands of the first full summer of operation. The system of chilled coils was designed to maintain a constant level of humidity of 55% all year round and have a cooling effect of melting 108,000 pounds of ice per day.

Lyle was totally impressed by Carrier’s research. He immediately drafted a letter to Buffalo Forge Company stating that “The cooling coils which we sold this Company have given excellent results during the past summer”. Willis Carrier had demonstrated his intellectual capacity and creativity to assemble everything to create something entirely new. The drawings were officially printed on July 17, 1902 and modern air conditioning had taken birth.

From this rich experience, Willis Carrier coined the term- Air Conditioning System as:

“AIR CONDITIONING IS THE CONTROL OF THE HUMIDITY OF AIR BY EITHER INCREASING OR DECREASING ITS MOISTURE CONTENT. ADDED TO THE CONTROL OF HUMIDITY ARE THE CONTROL OF TEMPERATURE BY EITHER HEATING OR COOLING THE AIR, THE PURIFICATION OF THE AIR BY WASHING OR FILTERING THE AIR, AND THE CONTROL OF AIR MOTION AND VENTILATION”.

AN APPARATUS FOR TREATING AIR:

After the success of the plant, Willis did not rest and instead began to investigate further to improvise the methodology. One of the engineers from Buffalo Forge Company, I.H Hardeman was a textile engineer. He suggested Carrier that his spray conditioner would be of great use in the textile industry, where the control of humidity was more challenging than the spinning factories. Hardeman then sold one of Carrier’s spray conditioner to Chronicle Cotton Mills in Belmonte, South Carolina. But the heat load of the equipment was too much for the Carrier’s device to handle and the machine met with a failure Carrier was quick to note the problem of dehumidifying and the exact value of moisture content needed. He expressed it in his own words:

“NOW, IF I CAN SATURATE AIR AND CONTROL ITS TEMPERATURE AT SATURATION, I CAN GET AIR WITH ANY AMOUNT OF MOISTURE I WANT IN IT. I CAN DO IT, TOO, BY DRAWING THE AIR THROUGH A FINE SPRAY OF WATER TO CREATE ACTUAL FOG. BY CONTROLLING THE WATER TEMPERATURE I CAN CONTROL THE TEMPERATURE AND THE SATURATION. WHEN VERY MOIST AIR IS DESIRED, I WILL HEAT THE WATER. WHEN DRY AIR IS DESIRED, THAT IS, AIR WITH A SMALL AMOUNT OF MOISTURE, I WILL USE COLD WATER TO GET LOW TEMPERATURE SATURATION. THE COLD SPRAY WATER WILL ACTUALLY BE THE CONDENSING SURFACE.

Carrier came to this conclusion while waiting for a train on a fog shrouded railway platform. He noted that fog is nothing but water vapor that has condensed out of air. From his calculations he realized that the amount of water vapor, air can contain depends on its temperature. When there is a drop in air’s temperature, the level of water vapor in it also drops. So, if humid air is cooled by spraying cold water, the amount of water vapor it can contain also drops. Gradually, despite the extra water being sprayed through it, the amount of water vapor in the air becomes greater than the maximum level of the water vapor the air can contain. When this happens, water vapor becomes fog or morning dews and the temperature where this happens is called the “airs dew-point”

It took Carrier some time to put forth his theory into practice. It was only in the year 1904 the method was formally implemented in a spray washer to his satisfaction. He applied for a patent for the same and he received it by early January, 1906. He gave a unique name for the discovery, “An Apparatus for Treating Air.”

The apparatus for treating air was the first spray-type air conditioning equipment and although it was termed as a revolutionary discovery, there were many questions raised on its credibility. Carrier realized that it was necessary to educate the market. He published a catalogue named, “Buffalo Air Washer and Humidifier” and received good response. The sales of the equipment began rising and Carrier’s reputation in the market soared. The net worth of the Company rose considerably.

Carrier also discovered a new theory, “The Law of Constant Dew-Point Depression. According to the law, the relative humidity of air remains constant as long as the difference between the dry-bulb temperature and the dew-point temperature is constant. In the year 1907, he discovered a design of an automatic control system for which he filed patent claim. Henceforth he was recognized as the “inventor of Dew-Point Control”

Carrier’s personal life received a jolt when he lost his wife Edith in the year 1912. In the same year he married Jennie Martin.

With the onset of world war in the year 1914, the Buffalo Forge Company decided to stick to the process of manufacturing. But young Carrier wanted to expand his horizon and so he and seven of his colleagues pooled their savings of $32,600 and established CARRIER ENGINEERING CORPORATION in New York on June 25, 1915. The seven young engineers were Carrier, J.Irvine Lyle, Edward T. Murphy, L.Logan Lewis, Ernest T. Lyle, Frank Sanna, Alfred E. Stacey, Jr. and Edmund P. Heckel.

RATIONAL PSYCHROMETRIC FORMULAE:

Around the same period, Carrier devoted more time in research of various aspects of the psychometric of evaporation and cooling and the entire mechanics of an air conditioning system. He prepared a conclusive document, a first of its kind in the field of air conditioning, titled “RATIONAL PSYCHROMETRIC FORMULAE”. His theory was presented at the annual meeting of the American Society of Mechanical Engineers held on 3rd December, 1911. Carrier listed the following principles on which his theory of evaporative method was based on: firstly -When air is saturated, the temperature is reduced as the absolute humidity is increased and the decrease of heat is exactly equal to the simultaneous increase in latent heat due to evaporation.

Secondly -As the moisture in the air is increased, the temperature is reduced simultaneously until the vapor pressure corresponds to the temperature, when no further metamorphosis is possible. This ultimate temperature is termed as the temperature of adiabatic saturation.

Thirdly – When an insulated body of water is permitted to evaporate freely in the air, it assumes the temperature of adiabatic saturation of the air and is unaffected by convection, i.e. the true wet-bulb temperature of air is identical with its temperature of adiabatic saturation.

From the above three principles, the fourth principle was determined:

And lastly The true wet-bulb temperature of the air depends on the total latent heat in the air and is independent of their relative proportions. The wet-bulb temperature is constant, provided the total heat of the air is constant.

Carrier’s paper was a landmark in the field of air conditioning and is also called “The Magna Carta of Psychometrics”. After it was published, the engineers agreed and accepted the theory of “control of air” as a part of their profession. Carrier’s chart was introduced in the engineering colleges and school textbooks as a part of their syllabus. His formula was translated in different languages worldwide and thus gave wide recognition to Carriers’ scientific invention.

CARRIER AS A WRITER:

Carrier believed in sharing knowledge and skill. He realized that the industry needed some sort of a guidebook from which engineers could derive data on air and the means to control it without referring to numerous books and catalogues. This concept of sharing knowledge was not very well accepted in the business circle. He began to write a catalogue on the subject which was published by the Buffalo Forge Company in the year 1914. He never stopped writing after the publication and would update his catalogue periodically.

BRAINCHILD BEHIND THE CETRIFUGAL MACHINE:

As time flew by, Carrier’s became more passionate about his work and discovered certain inadequacies in the refrigeration machinery then in use. He eventually introduced a new paper titled “DEVELOPMENT POSSIBILITIES OF IMPROVEMENT IN REFRIGERATION” which laid the foundations for a new type of machine. Carrier stated:

“The entire system of electric transmission has been developed from nothing to an enormous industry with relatively simple motors that are high-speed rotative equipment. The industry has gone from low-speed reciprocating steam engines to high-speed rotativeturbines. Pump machinery is rapidly changing from reciprocating types to high-speed rotativepumps for both liquids and gases. Modern power plants have installed high-speed direct-connected, centrifugal, boiler-feed pumps almost exclusively in replacing the old type of steam-driven reciprocating machines”.

Refrigeration, though classed among the older mechanical arts, has shown no such material progress. The same improvements that have taken place in electrical transmission and in steam machines and pumps must come in refrigerating machines”.

The paper was the origin of the concept of the centrifugal refrigeration machine. Its main characteristic was the direct drive suitable for high-speed operations and heat exchangers that were simple and effective both performance wise and cost wise.

The new machine introduced a new refrigerant- DIELENE, which was non-toxic and had features suitable for and advanced mechanical equipment along with many other new components. The machine was tested several times and gradually installed in Carrier’s factory in May 1922. The first centrifugal machine or the ‘chiller’ was actually sold in 1923 to a company named W.F. Schrafft and Sons Candy in Boston and was installed for the first time in Philadelphia to a candy manufacturer Stephen F. Whitman and Son. The chiller and was in use till 1951.

The sales of the machine increased considerably and no compromise was made in its quality. Carrier gave strict instructions to its workforce to test each machine thoroughly. In the process, defects were thoroughly investigated, amended and gradually upgraded. The centrifugal machine was a result of sheer hard work and research by Carrier and his team and the motive was to produce a perfect working commercial machine. Thus Carrier pioneered the first major mechanical refrigeration after David Boyle who had designed the original ammonia compressor way back in the year 1872

SUCCESS IN PHASES:

The carrier did not achieve success overnight. It was in phases and each phase was marked by a distinct development. In the year 1923, Carrier entered into partnership with three large fan manufacturers and formed the Aerofin Corporation. Aerofin was involved in the production of lightweight, brass and copper alternative to bulky cast-iron heat exchangers. In the subsequent year he installed three,195-ton centrifugal chillers at J.L. Hudson Company, Detroit’s largest departmental studio. The main motive behind the installation was to encourage shoppers to “shop and still be cool”.

Next, Carrier set his eyes on movie theatres. He installed the first air conditioner successfully at Sid Grauman’s Metropolitan Theatre in Los Angeles followed by The Palace Theatre in Dallas and Texan in Houston. All the three theatres had Carriers’ system including the Centrifugal Chillers. As expected, theatres became the place where people enjoyed watching movies with comfort cooling for the very first time.

In the year 1925, Carrier installed an air condition in the engine room of a destroyer in the United States Navy. This was indeed a matter of pride for Carrier Corporation. Skyscrapers were next which caught Carriers’ attention. In the year 1926, T.W.Patterson Building in California became the first multi-story building to install the Carrier’s air conditioners. Within a few months Carrier installed air conditioners at the National Broadcasting Centre, a 16 floor Building in New York City. A 75 ton compact centrifugal machine brought comfort to the Paramount Industry allowing an exposed negative to be developed and projected in just 20 minutes from receipt. One success led to another and in the year 1928, The Frost National Bank in San Antonio became the first bank to install Carrier’s air conditioners.

As Carrier’s sales captured American Markets, his sales reached to new depths internationally. In the year 1928, Carrier Corporation was awarded contract to install two 76-ton centrifugal machine in the Morro Velho Gold Mine in Brazil to improve the working condition of the miners. To meet the ever increasing demand for his air conditioners, Carrier opened new offices in Sydney, Paris, Bombay, Johannesburg and Stuttgart gradually.

Carrier did not aim merely at capturing larger markets and public places for his installations. He was also providing ‘unit air conditioners’ to small retailers and departmental stores. He sold his first unit air conditioner to an egg storage Company in New York in the year 1928. In the same year he entered into a partnership deal with J. Irvine Lyle. After a few months, Carrier and Lyle felt the need to improve the safety standards of their employees working in their plant. Hence Carrier University was set up with six professors, twenty students and Carrier as the President. Within a year the Company initiated a Safety Organization with seven safety inspectors.

As business boomed, Carrier bought new property in New York and shifted his older Carrier plant to the new premises while the new Lyle plant became the base of unit products. A year later, the Company set up its third plant in Pennsylvania. This increased Company’s manufacturing capacity and in one of the meetings the Chief noted “From none in 1921 to over five acres in 1929”.

Thus within a very short span of time Carrier’s centrifugal refrigeration had brought the Carrier’s Company to movie theatres, Banks, shopping malls, offices, Mines, Broadcast Studios and Naval Ships.

In February 1929, Willis Carrier gave a speech to his work force in which he stated “Twenty five years ago ‘Air Conditioning’ was an unknown quantity either in theory or practice. In years to come the Chief forecast, “air conditioning and cooling for summer may become a necessity rather than a luxury, and we will look upon present times as marking the end of that ‘dark age’ in which there was but relatively little cooling for human comfort”.

THE GREAT DEPRESSION:

All was going well in term of sales and profits soared rapidly. But in October 1929, Black Thursday as it was named, witnessed the total collapse of the stock market and thus began the longest, deepest depression in world history. Carrier blessed with strong acumen forecasted that to stay in the market, the Company has to remain focused and innovative. Instead of worrying over the problem he decided to study the adverse situation carefully. The economy was undergoing tremendous change and Carrier observed that every manufacturer suffering loss began looking to air conditioning as a lucrative field. He once stated “One of the worst features about worrying is that it destroys our ability to concentrate. When we worry, our minds jump here and there and everywhere and we lose all our power of decision. However when we force ourselves to face the worst and accept it mentally, we then eliminate all these vague imagining and put ourselves in a position which we are able to concentrate on our problems”.

Carrier planned his marketing strategies well and eventually he decided to merge his Company with BRUNSWICK KROESCHELL Company manufacturing small commercial refrigerators and with THE YORK HEATING AND VENTILATING CORPORATION, producing unit heaters. Armed with both engineering and manufacturing expertise, the new Carrier Corporation introduced a new slogan, “WEATHERMAKERS TO THE WORLD”.

Soon after the merger, Carrier began working on the railroads. He understood that this segment had lot of potential to generate revenues and greater customer satisfaction as he noted “While theatres, departmental stores, restaurants have undoubtedly played an important part, it is believed that the greatest impetus to public acceptance came through the wholesale adoption of air conditioning by the railroads”. He began his research on a steam ejector that used water as the refrigerant. The first demonstration of cooling a railway passenger car was made in Baltimore in the year 1930. A radio commentator Lowell Thomas reported live, “A most imposing list of railroad executives journeyed over to New York, New Jersey, and there… they stepped into an old obsolete car. Outside it was warm as blazes. Inside the car the temperature was 74, cool and pleasant. And what made it cool? Why, steam! Yes-hot steam! Scalding hot steam! A new steam has been devised for cooling railroad trains”.

This was Carrier, a genius. It was way back in 1903, he found that water could be used to dry air and nearly a generation later he realized that steam could be used to cool water.

A very interesting incident which showcases Carrier’s disciplinarian attitude was when he approached Cloud Wampler, a banker in Chicago who managed the building which housed one of Carrier’s offices. The Chief wanted a reduction in rent and one conversation let to another with Wampler later on joining Carrier as his financial advisor. In one of his cost cutting instructions, Carrier said “We will not do less research and development work. We will not discharge the people we have trained, and we will work for nothing if we have to”.

CARRIER-A TECHNICAL WIZARD:

Carrier did not become an expert on air conditioning system overnight. He would ponder over a technical problem for several years and would never abandon it. If he was unable to find any solution to a technical problem, he would postpone it but never gave up completely. If for some reason he found out that his discovery will not be met with commercial success, he would abandon it. He once quoted “I fish only for edible fish, and hunt for edible game- even in the laboratory.”

There is a very interesting incident which depicts the sharp intellectual mind of Willis. Once a chemist explained him the production of ‘Freon-12’ a colorless gas originally called ‘DICHLORODIFLUOROMETHANE’ and according to him there was no way to procure the gas except in the industrial process. Carrier was confident that this gas could prove to be an excellent refrigerant for the centrifugal compression. He began pestering the chemist for the formula and eventually succeeded. The data was written in pencil on worksheets and the chemist removed Photostat copies of the same and supplied it to Carrier along with a sample of the fluid. After a lot of research and tests, Carrier developed a new type of refrigerant known as Carrene-2 in the year 1930. This refrigerant was far more superior and efficient than the prior systems. The first Carrene-2 refrigerant was installed in the U.S. Court House in the New York City and ran successfully for 16 years without a single call for servicing. Whew! What an achievement…

In the year 1931, Carrier Corporation demonstrated their new invention by introducing the ‘Atmospheric Cabinet’, a room cooler with a fan, cooling coil and filter enclosed in a cabinet, and a refrigerating machine located outside the room.

Throughout the decade, Carrier Corporation’s business grew rapidly. They began to venture in other sectors as well like large luxury cruise liners, Queen Mary and Queen Elizabeth. They also entered in the medical sector by providing air conditioners to hospitals in Mexico City, Lenox Hill Hospital in New York and to hospitals in other countries like Cairo in Egypt. With business expanding despite the depression, the Company paid equal attention to its business policies and practices. By the end of June 1933, some 30 dealers purchased Carrier’s air conditioners worth $500,000.

On November 18 1937, a large crowd of more than 700 people gathered in the Hotel Syracuse ballroom to welcome the City’s newest and most successful industry. Post merger Carrier Corporation had emerged as one of the most prominent Company and it was possible due to the combined efforts of the management and 600 employees of Carrier Corporation.

INTRODUCING THE CONDUIT WEATHER MASTER:

Carrier added another feather to his hat when he invented the “Conduit Weather Master” better known as “Air Handling Unit (AHU)”. The invention was inspired by the problems posed by skyscrapers i.e. the height and the amount of rooms per floor which in turn affected the outside ventilation (OA).

A standard AHU (conditioning apparatus) is an important element of the air cycle. The basic components of the AHU includes fan motor, cooling coil and modulating face and bypass dampers, mixing boxes with the flow of air in and out of the air openings. This resulted in increased size of each AHU including the OA duct. Carrier’s aim was to save space by compact ducts and ithe introductionof the Conduit Weather Master was the answer to success.

The OA rooms are large and the room requires the removal of both sensible heat and latent heat. Latent and sensible heat, are types of energy released or absorbed in the atmosphere. Latent heat is related to changes in phase between solids, liquids and gases whereas sensible heat is related to the changes in temperature of a gas or object with no change in phase. Carrier decided to cool the entire OA flow and to bring it down to the dew-point and that too in the remote OA unit. The result was satisfying as the space required for the OA duct was significantly reduced. The high velocity (20 meters per seconds) Ducting used to carry the OA is the ‘Conduit’ in the Conduit Weather Master.

The Company installed its first weather master conduit in the Pentagon and subsequently at the Statler Hotel in Washington D.C. This was the last installation by the Company before U.S.A’s entry in the World War II in the year 1939. In the same year Lyle was elected as the President of the Carrier Corporation.

On being elected as