CHAPTER XII 

 STEAM INSTALLATION* 



General Principles. In steam heating 

 there is no circulation in the same sense that 

 there is in hot water heating, but the steam 

 is conducted into the heating coils, where it 

 condenses. In condensing it gives up its 

 "latent" heat. The water of condensation, 

 which occupies only about 0.017 part of the 

 space occupied by the steam, finds its way 

 back to the boiler either by flowing back 

 through the supply pipes, or through return 

 pipes connected with the opposite ends of the 

 coils. The latter system is most commonly 

 used in greenhouse heating. 



In contrasting steam and hot-water heat- 

 ing it is well to keep in mind the fact that 

 only 180 B. T. U. are required to raise one 



*In order to avoid repetition steam heating is- discussed 

 largely in contrast to hot water heating, as described 

 in the preceding chapter. Both chapters .should be 

 read by one wishing to inform himself on steam 

 heating. 



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