Cooling passenger cars

I am currently about 3/4 of the way through my second reading of FDR's Funeral Train.  In this book they note that Pullman used blocks of ice in bunkers with fans blowing air over them to generate  air conditioning in the 1930's and '40's.  

I suspect this may be a bit earlier than the period you are interested in though.

Curt

Here's how the Santa Fe did it:  LINK

Rusty

The first systems used ice. It melted and created cold water, which was plumbed to radiators in the roof of the car. Fans were powered by belt-driven generators, with battery back-up, Ice was inexpensive in theory, but the cars needed lots of it to maintain a cooling effect. ISTR that a typical car used several hundred pounds, maybe closer to a thousand, per hour.

Next was steam-absorption systems; the steam came from the locomotive. These systems were heavy and bulky, and were replaced by an ingenious system invented by Mr. Carrier.  It used pony generators mounted under the cars to provide the electricity for the fans, and used a drive shaft connected via a gear-box to one of the axles of the car for the heavy HP demands of the compressors. The (governed) shaft turned the A-C compressor, under the car. When the train was stationary, shore power could be plugged in to keep the system cooling.

After steam, small gasoline-, Diesel-, or propane-run 4-cylinder engines beneath the cars were used. Cars with removable/replaceable propane tanks could be serviced easily at stations, and during stop-overs. The tanks could be removed before a train entered a city that prohibited them.

HEP is the latest method, for non-electrified roads, and I suppose you could call electrification sources "HEP" since the juice comes from the head-end electric locomotive. 

This is just a quick over-view from memory, and I'm sure that there are some experts here who will contradict me.  I was told to write a thesis for a college English class "on any subject that interests you" back in nineteen- (mumble) so I wrote about passenger trains. I got a good mark, as I recall, not just because the professor was a railroad enthusiast, a fact that I knew because he and I would chase trains late at night in Potsdam, NY. 

Thanks for the info guys.

Don't be too sure, Curt, in your suspicions.  I was around during several of Mr. Roosevelt's terms.  I can recall asking my mother if Democrats always nominated the incumbent and Republicans someone else.

Air conditioning with steam seems counter-intuitive, but it worked. I wonder how much of an extra load this placed on the motive power?

https://en.wikipedia.org/wiki/Steam_jet_cooling

Steam jet cooling uses a high-pressure jet of steam to cool water or other fluid media. Typical uses include industrial sites, where a suitable steam supply already exists for other purposes or, historically, for air conditioning on passenger trains which use steam for heating. Steam jet cooling experienced a wave of popularity during the early 1930s for air conditioning large buildings. Steam ejector refrigeration cycles were later supplanted by systems using mechanical compressors.^[1

Principle

Steam is passed through a vacuum ejector of high efficiency to exhaust a separate, closed vessel which forms part of a cooling water circuit. The partial vacuum in the vessel causes some of the water to evaporate, thus giving up heat through evaporative cooling. The chilled water is pumped through the circuit to air coolers, while the evaporated water from the ejector is recovered in separate condensers and returned to the cooling circuit.

Usage

The AT&SF railroad (Santa Fe) used this method, which they called "Steam Ejector Air Conditioning", on both heavyweight and lightweight passenger cars, built until the mid-1950s.

There are also refrigerators that work solely on compressed air: the gas expands through a nozzle and absorbs heat. I heard of these being tried out for refrigerators in locomotive cabs; they are simple but relatively inefficient and NOISY.

https://en.m.wikipedia.org/wiki/Vortex_tube#History

Ace posted:

Air conditioning with steam seems counter-intuitive, but it worked. I wonder how much of an extra load this placed on the motive power?

The only thing about steam ejector air conditioning is that Santa Fe passenger trains always had to have the train lined steam operating.  Thus, the 300 and 325 Class rednose F7's were A-B-B units instead of A-B-A.  (Santa Fe F3A and F7A passenger units had vertical water tanks at the rear of the engine room, and the F3B and F7B units had the steam generators.

I've read that the C&O George Washington was the first air conditioned train in service. Anyone know how that was accomplished?

Number 90 posted:

Ace posted:

Air conditioning with steam seems counter-intuitive, but it worked. I wonder how much of an extra load this placed on the motive power?

The only thing about steam ejector air conditioning is that Santa Fe passenger trains always had to have the train lined steam operating.  Thus, the 300 and 325 Class rednose F7's were A-B-B units instead of A-B-A.  (Santa Fe F3A and F7A passenger units had vertical water tanks at the rear of the engine room, and the F3B and F7B units had the steam generators.

Oh, dear, I have two F3A ATSF WB diesels on a passenger train.  My customers are roasting!

I think the GN had extra water tanks in the A's, and the steam generators in the B's!