All Aboard!
(Syracuse, N.Y., November 18, 2002) ¿ People all over the world travel both conveniently and comfortably everyday by train. Europe's TGV (Train Grande Vitesse) transports travelers long distances quickly. High-speed commuter trains are common in Japan, and along the "Northeast corridor" of the U.S., quickly transporting people between Boston, New York, Philadelphia and Washington, D.C.
But passengers haven't always been able to enjoy the comfortable train ride of today. In the early days, trains had little ventilation and were powered by steam and coal, which created a lot of heat. Many attempts were made to make train travel more bearable, but most failed. Back in 1884 the Baltimore & Ohio (B&O) Railroad tried to cool a passenger car by passing air over a huge icebox built at the head end. It didn't work.
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There were several aborted attempts to provide cool comfort to rail passengers. The problem was that the air conditioning systems of the day were too large to be installed on rail cars. So much of the focus was on pre-cooling the cars while they idled in the station. This was time consuming, costly and ineffective. For example, in 1907, while designing a system to cool freight cars for the Sante Fe railroad, Willis Carrier proposed a mechanical room below the station platform in which air would be cooled for delivery to the cars while they stood in the station. The system was never installed.
The 1920s advent of the centrifugal chiller, which reduced the size of the air conditioning unit, led to a solution for trains. In 1929, B&O asked Carrier to design an air conditioning system for a passenger car, to be tested in the railroad yards in Baltimore. Approaching the seemingly complex problem with the same dogged determination and drive to break things down to their simplest terms, Carrier laid out the first on-board system and installed it in B&O Coach #5275.
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In 1930, after running tests on coach # 5275, B&O ordered an air conditioning system for "The Martha Washington," its diner car on "The Columbian," which operated between Washington, DC and New York. To test it, the car was heated to 93 degrees F, then the heat turned off and the air conditioning system turned on. In 20 minutes, the temperature of the car was a comfortable 73 degrees. Carrier was on track!
They took the train ¿ and The Martha Washington -- that summer to Minneapolis for a special meeting of the American Society of Heating & Ventilating Engineers. Later they took it to Atlantic City, N.J., to a meeting of the American Railway Association. Some 3,000 railroad engineers observed that while temperatures soared to 96 degrees in adjacent cars, it was a cool 73 in the dining car.
It wasn't long before the Sante Fe, the Missouri, and the Kansas & Texas Railroads all ordered systems.
Not one to rest on his laurels, Carrier purchased an old coach for $400 and brought it to the plant in Newark. His engineers built a shed over it and installed equipment to replicate summertime conditions. They created temperatures up to 106 degrees and even created a wind tunnel to simulate the effect of a moving train. They put 100W light bulbs in each seat to simulate the amount of heat given off by a passenger.
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By 1931, Carrier had developed a more efficient means of cooling a railroad car, using a 5-ton steam ejector refrigerating machine. And the orders poured in. The result was not only a new market for air conditioning, but also an expansion of old markets, because the cool railroad cars found their way into every town and village across America, exposing air conditioning to the masses while impressing businessmen who traveled by rail.
In 1964 Carrier supplied air conditioning to the Chicago Transit Authority (CTA) for 180 cars to be used on the Lake and Douglas routes.
In 1969, Carrier made history once again with a project that set the benchmark for modern train travel. In that year, high-speed Metroliner railroad trains made their debut making round trips between New York City and Washington, D.C. These "trains of the future" were served by enough air conditioning to cool four average-sized homes!
Each car was equipped with a 12-ton capacity cooling system using major components supplied by Carrier's special products division. The only parts of the systems visible to passengers were center ceiling air diffusers, which were blended into the décor.
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The evaporator coil and fan sections were hidden above the ceilings. Electric resistance heater banks on overhead units were supplemented by convection heaters hidden inside each car's walls. The evaporator fans handled 600 cubic feet of fresh air per minute and 1,200 cubic feet of recirculated air per minute.
The motor compressor assembly, air-cooled condensing unit, motor starter and controls are concealed under each car. The controls maintained a constant temperature in the cars despite outdoor temperatures.
The Metroliners were the latest in high-speed railway cars, and each was self-propelled so that the length of a train may be varied with the expected passenger load for any given hour.
Needless to say, even more developments in passenger comfort have been made since 1969. As the train industry moves towards the future, new technology is being developed for HVAC systems in trains. "Green" air conditioning, similar to what is used in today¿s commercial aircraft, is the future of rail HVAC. It is already at work in places like Germany. In these systems, an air compressor heats and cools the air by blowing air through a turbine. Air is expanded and then decompressed, removing the heat from the air and returning cooler air to the car. This eliminates the need for refrigerant, pumps and discharge/suction lines.
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