AC Units on ACL Heavyweight Pass. Cars : LUSENET : ACL and SAL Railroads Historical Society : One Thread

Does anyone have any information on the AC units applied to the ACL's heavyweight coaches and diners - particularly those with turtle back roofs. A review of diagrams for ACL conventional passenger equipment indicates that 6 to 8-ton AC units manufactored by the SCH&L Co. were used. The presence of these AC units were indicated by what appears to be a large flat "hatch" and vents of various sizes typically located at one end of the car. An overhead shot of car equipped with this type AC unit would be helpful as would any dimensions of the "hatch" and vents. Does anyone know of the existence of any former ACL coaches so equipped that could possibly be photographed/measured? Thanks in advance for any information.

-- Buddy Hill (, November 30, 2001


The drawing I have (on microfilm N-237) shows two roof hatches, one on top tof the other. The larger hatch is 4'-5 7/16" OAL along the centerline by 4'-8" OAL across the car. The hatch is curved to fit the Claristory roof contour. There is a 2-1/2" flange all around the hatch for bolting to the roof, The bolt holes are on 8-1/2" centers.The smaller hatch is a square 23-3/4" OAL. It also is curved to fit the roof contour. The drawing indicates it is for a steam injector type of AC. The car series is a coach 1060-1089. Let me know if you need any further info.

-- Ron Dettmer (, December 03, 2001.

The answer depends upon the time the cars were air conditioned and/or rebuilt. ACL in the pre-war period was proponent of steam ejector air conditioning. This type of AC did not require as large an electrical load as did an electro-mechanical unit since it used the energy contained in steam. The amount of steam used was equal to the amount of steam used for heating the cars in the winter and since most of the locomotives had a ready supply of steam, it was an economical choice. The units themselves were very large and required more space than did equivalent electro-mechanical units. A steam ejector AC car had large vents along the roof-this is usually a good identification method.

Post war, the ACL realized that with the coming of diesel locomotives, steam would not be as readily available as it was, and that steam ejector units did require more maintenance than did electro-mechanical units. So-all post war air conditioning was ellectro-mechanical and when AC rebuilt cars, such as the modernized A-15 cars or the rebuilds of the 1939 coaches, the cars were refitted with electro-mechanical units.

I have some photos of steam ejector units at home in a copy of the 1940 car builders cyclopedia. Let me know if you are interested.

-- Michael Savchak (, November 30, 2001.

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