I know that EMD “F” units were extended 4 feet to accommodate a steam generator for passenger service. Here are my questions:
Was steam piped back from the locomotive to heat the cars? And if so, wouldn’t the steam cool in a longer consist?
In the steam era how were passenger cars heated?
the goat 
I believe I can help answer the first question. The steam was piped back, and yes, cars further back were, well, brrrrrr!!! For this reason the Boston & Maine Railroad limited the amount of passenger cars an F7 could haul to 7 or so (I don’t remember the number very clearly, this is from the book High Green and the Bark Peelers), even though the locomotive could haul more based on tonnage. Any more than that figure, and an extra unit was tacked on.
…My memory tells me it was steam. Depending how it was regulated…{controlled}, they were either pretty warm to not warm or sometimes pretty comfortable. That’s my memory of a bit of travel in that era…Don’t know how the steam was controlled to regulate the “right” heat in the car.
The PRR cars I rode according to the engineers I spoke to used steam pumped into
radiators that were mounted on the bottom of each side of the cars
It was steam, right up to the Amtrak era – and even somewhat into, as it took awhile for cars to be converted to electric (head end power) heat. Depending on the train, and the equipment, and the maintenance of the equipment, steam heat could be very good or very bad, and it didn’t necessarily get worse the farther back you went. Without getting into a dissertation on how steam heat works, suffice it to say that if the steam generator or the engine had enough capacity, the heat came from ‘radiators’ in each car (there were a variety of different schemes, depending on the kind of car), and each car’s temperature was independently controlled in the car. Maintenance was a big issue – not only was there the problem of steam leaks (particularly where the hoses coupled) but there were the traps and valves on each car which had to work properly.
The steam generators on diesels were, fundamentally, boilers not unlike the ones in a steam heated house of the era. They worked pretty well, most of the time… but they could, and sometimes did, have firing problems which could result in plentiful black smoke or even explosions in the fire box – which rarely damaged anything beyond the boiler, but could really shake up the engineer and fireman!
Interestingly, on some services steam was also used to cool the cars – which also worked well, although it seems weird to use steam (hot) to produce cooling!
…Using steam to “cool” cars is not much more unusual than using natural gas to “cool” via the mechanism in certain refrigerators. Such coolers were produced and in use in homes back in the 30’s. Believe they featured practically no moving parts. Trying to remember the manufacturers name…Was it Servel…
…Trying to remember the heating system in PRR cars…Believe the steam piping was at the corner of the floor and the side wall…enclosed in a lovered incasement of sort. Radiating heat out from it.
Servel it was indeed and similar units are in some RVs today. But I don’t know how they worked.
Prior to VIA, and for their first decade, CN would have a steam generator car on the end of most of their mid-winter trains over ten cars. Riding an eleven car VIA “Cavalier” Montreal-Toronto, was like being in a sauna, thanks to having two sources of steam for heat! WHEW!
Yes to the first part and a qualified yes to the second part. The problem was as much steam leaks as it was steam cooling. The drop in steam temperature and pressure wasn’t as bad as it might seem since the steam pressure was dropped to slightly over atmospheric before it went into the heating coils.
John H. White, Jr’s The American Railroad Passenger Car does a good job of explaining how the steam heat system came to be and what it replaced. It is a good all-around source on passenger car design, construction and auxiliaries from 1830 to about 1970.
Instead of a steam generator, the steam came directly from the locomotive boiler, one of the distinguishing characteristics of a passenger locomotove was a steam connection (some frieght engines were so equiped to allow use on passenger trains). The steam generators on diesel locomotives were added for backwards comatibility.
The earliest diesel trains often used heat from the engine for train heat - but experience dictated that a steam generator be added. The Butte, Anaconda and Pacific used electric heating after the line was electrified in 1913.
Hey, and let’s not forget this important detail with steam heated trains: the trailing steam pipe valve on the trailing car always was cracked open just a wee bit. By doing so, this allows of continuous flow of fresh steam from the locomotive to the last car and all of the equipment in between, and it also serves as the point where any condensation could be discharged.
In addition to passenger coaches, diners, sleepers, lounge, and observation cars, the head end equipment such as baggage, mail storage, and Railway Post Office cars also had steam pipes and radiators. Certain piggyback flats and Flexi-Van flats built for passenger service had well insulated pass-through steam pipes as well.
On December 22, 1971, I caught the combined Super Chief / El Capitan at Barstow, Calif. for a ride to Chicago. The weather east of California got pretty cold in spots so the Santa Fe tacked-on a baggage car equipped with two Vapor brand steam generators to the rear of the train. I was riding in a bedroom of the last sleeper and was toasty warm throughout the trip.
The Servel refrigerators used an ammonia absorption cycle - the heat was used to separate the ammonia from the water. This cycle is very sensitive to the fridge being tilted and probably would not work well on a RR passenger car.
Steam cooling on passenger cars was doen by the steam ejector method - the steam was used to create a vacuum which then would cause the water to boil at low temperatures. The cooled water would then be circulated through a heat exchanger to cool the air. Problems with this system were a high use of steam (more than for heating) and the air couldn’t be cooled as much as with a freon cycle.
In Japan the transition was from steam to catenary, and the catenary motors did not have train heat boilers. The solution was to mount the boiler of an obsolete locomotive in something resembling a baggage car with a coal bunker at one end to provide steam.
The down side was, many of the lines where these things ran had tunnels - often long ones. With no exhaust to provide draft, the coalburners produced copious quantities of black smoke. They also smelled pretty terrible. I can imagine the reaction of someone who wants to ban smoking everywhere, if faced with one of these!
In spite of that, I’m still going to have to model one (or more) for use on my older passenger trains. After the equinox, it gets pretty cold in the Central Japan Alps.
Chuck (modeling Central Japan in September, 1964)
Pennsy GG1 electrics had an oil-fired steam generator just like a diesel locomotive.
Before steam heated passenger cars, cars were heated by coal stoves. If you were near the stove you were too hot and and if you were not, you froze. It is also my understanding that those stoves started lots of fires when wooden passenger cars derailed. Steam heat was a great step forward.
dd
Yep, very good! Amtrak slowly converted sets of Heritage Fleet cars to HEP ( Head End Power). The last trains long distance trains to be converted were on the east coast in 1981. Sad for me, slightly, because that’s when the last SDP40fs went “bye-bye” on the Silver Service trains. The F40 was virtually Amtrak’s mascot.
Amtrak’s Beech Grove shop crews did an excellent job and those HEP Heritage cars were such a joy to ride in. Upset me when Amtrak was forced to retire most of them because of the toilet isse.
The three biggest user of steam ejector AC were ATSF, NYC and Milw.
On of the worst US RR accidents of the 19th Century (maybe ever) was when a bridge on the LS&MS collapsed under a train in the winter and the coal stoves ignited the wooden cars. Doesn’t bear thinking about!
In NSW Australia we used what were known as Mclaren foot warmers which had a chemical inside which when taken out of boiling water or a stove would hold its heat for a number of hours. When the RUB/HUB air-conditioned cars were introduced in the 1940’s these used Head End Power from day one with power vans on each train which provided 415V 3-phase 50 hz (Australian Standard industrial frequency) to run both the Air Conditioning and the Buffet/Dining cars. It is not a wide known fact that the then NSWGR were one of the first users of industrial frequency head end power in the world. Thus reducing both capital and maintainence costs over the long term as standard industrial equipment was used. It was found in NSW that the other systems around at the time namely 32v/110v powered by either axle mounted generators/steam turbo generators were both inefficent and more costly to purchase /maintain compared to freon based systems running on industrial frequency with head end power.
Now to bring a US focus back to the post. Did the Fish belly Keystone Cars use Head End Power with off the shelf industrial equipment. As in White’s book he makes mention of power vans being used but I don’t know wether these used industrial voltage and frequency equipment. Which in the US would be 220V 3 phase 60hz
Not only did you have to have steam escaping from the rear of train also had to have valve cracked on head end of lead engine.
We used to figure 10 lbs steam pressure per car was about the proper amount on the Rock Island. Winter was the real challenge. As soon as the train got moving and snow started swirling under the cars it really cooled off the steam pipes. You’d be sitting at a station stop with 160 lbs of steam pressure on a 10 car train and would be lucky to have 60lbs when you reached 79mph.
A very interesting question, especially about cars that were heated by steam[au]