| Show 0 5 ap i ld R roger 0 9 e r B edff W whitman h i t M a n 0 MAI im CA FOR ECONOMY COAL OR OIL A A QUESTION that continually arx comes up is on the relative economy of heating a house by coal or by oil there can be no general answer because of the many conditions that enter in for one thing a coal fire run by hand may not be efficient much good coal may go out with the ashes it i is s unusual to find a household heating plant stoked by hand in which as much as 60 per cent of the heat in coal is actually utilized an oil burner on the other hand when properly installed and adjusted runs with much higher efficiency and for this reason a comparison of operating costs might be unfair with a coal stoker a more accurate comparison can be made because of the higher efficiency that is possible with a machine over hand methods the running conditions of an oil burner are quite different from those of a coal fire A coal fire continually delivers heat and with no extreme difference in temperature between smoldering and burning with full draft an oil burner on the other hand is either delivering no heat beat at all or producing a temperature far higher than a coal fire running at full blast in a boiler designed for coal the movement of hot air and gases through its inside passages is comparatively ively slow there is ample time for heat to be absorbed by the metal with an oil burner attached to the same boiler the heated gases pass through at much higher speed a speed that may not allow sufficient time for the metal to pick up a large proportion of the heat much of the heat is wasted up the chimney some boilers designed for coal have long lone passages and are well suited to oil this is the case with so called 11 square boilers that are made up of vertical sections in round boilers the inside passages are shorter a and nd more direct they give good efficiency with coal but are not well adapted to oil moving at high speed the heated gases are in contact with the boiler surfaces for too brief a time for maximum heat beat to pass to the metal boilers with built in oil burners run with high efficiency that is less of the heat is wasted up the chimney than is the case when an oil burner is adapted to a boiler designed for coal boiler and burner being designed for each other a high percentage of heat is utilized in heating the house economy in burning oil thus depends on the conditions with a boiler designed for the quick absorption of heat the cost of oil may be low but whether or not it is less than the cost of operating the same boiler with coal will depend on the efficiency with which the coal is burned Q by roeer B whitman service |
