Steam generator (railroad)

A steam generator is a type of boiler used to produce steam for climate control and potable water heating in railroad passenger cars. The output of a railroad steam generator is low pressure, saturated steam that is passed through a system of pipes and conduits throughout the length of the train.

Steam generators were developed when diesel locomotives started to replace steam locomotives on passenger trains. In most cases, each passenger locomotive was fitted with a steam generator and a feedwater supply tank. The steam generator used some of the locomotive's diesel fuel supply for combustion. When a steam generator-equipped locomotive was not available for a run, a so-called "heating car" fitted with one or two steam generators was inserted between the last locomotive in the consist and the rest of the train.

Steam generators would also be fitted to individual cars to enable them to be heated independently of any locomotive supply.

In Ireland, Córas Iompair Éireann used "heating cars" as standard and CIÉ diesel locomotives were not fitted with steam generators.

During the early days of passenger railroading, cars were heated by a wood or coal fired stove—if any heat was provided at all. It was difficult to evenly heat the long, drafty cars. Passengers near the stove often found it uncomfortably hot, while those further away faced a cold ride. The stoves were also a safety hazard. Often cars were ignited by embers from the stove, especially in a wreck, when a dislodged stove would overturn, dumping burning coals into the car.

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Wikipedia