SOME EXPERIMENTS IN HEATING BY GAS. 



BY CHARLES 



THE October number, 1890, 

 of The American Garden, a 

 description was given of a 

 tubular boiler, used to heat a 

 small greenhouse. The boiler 

 was of sheet metal, 27 inches long and 

 6 inches in diameter, with four i-inch 

 flues. A diagram of the boiler may 

 be found on page 612, Vol. XI. 



In order to make further experi- 

 ments in heating, this same boiler was 

 again used this last season with com- 

 mon street (water) gas, and the re- 

 sults of these experiments are here presented to 

 The American Garden readers in the hope that 

 they may prove of interest to both greenhouse 

 owners and housekeepers. The object of the ex- 

 periments was to ascertain how far gas fuel could 

 be used to heat two rooms in a dwelling house. 

 One of these rooms is a kitchen, in which gas is 

 used for cooking, and the other room is a chamber. 

 Both rooms are on the northeast corner of the 

 house, the building being a well built wooden 

 house, but standing on top of a high hill, fully ex- 

 posed to the east wind blowing directly over Long 

 Island Sound ; the water being less than a mile 

 distant. As gas is used for cooking, the kitchen is 

 apt to be cold at night and when the stove is not in 

 use. The chamber, immediately over the kitchen 

 was kept warm by a small parlor stove. The ob- 

 ject sought was to warm both rooms by means of a 

 gas flame in the cellar. 



The matter was laid before an expert m heating 

 by hot water, and two radiators were selected, one 

 of three sections for the kitchen, and one of four 

 sections for the chamber. The upper room con- 

 tains 8go cubic feet of air space and has one win- 

 dow facing east, giving 15 square feet of glass sur- 

 face. The two outside or exposed walls gave 147 

 square feet of wall surface ; the other walls did 

 not count, as the next rooms were warmed by the 

 furnace in the cellar, and did not extract heat from 

 the room. The kitchen contained 1224 cubic feet, 

 had 25 feet of glass surface and 200 feet of out- 

 side wall. These points have to be considered, be- 

 cause, in estimating the radiating surface needed 

 to warm a room by hot water, it is, first of all, ne- 

 cessary to find out how fast the heat in the room 



BARNARD. 



escapes through the outside walls and the windows. 



It is precisely the same in a greenhouse at night, 

 and on cloudy days. The glass and all the walls 

 radiate heat, so that, practically, a greenhouse, and 

 in a less degree every building, is itself a radiator 

 giving off heat to the outer air. A stove, furnace, 

 boiler or other appliances within a greenhouse or 

 other building simply acts to supply the continual 

 loss by radiation. This loss through glass and 

 through wooden, stone or brick walls is reckoned 

 in heat units ; so many heat units per hour per 

 square foot of surface, according to the difference 

 between outside and inside temperatures. 



The two radiators were placed one above the 

 other in the two rooms and connected by wrought- 

 iron pipes, and the boiler was placed in the cellar 

 below. The pipes from the boiler are one-inch 

 pipes. This was a defect. It would have been bet- 

 ter to use li -inch pipe. From these pipes upward 

 to the first radiator i]--inch pipe was used, and above 

 this radiator |-inch pipe. This tended to divide the 

 volume of water in the right proportions for the two 

 radiators. To provide for the expansion of the water 

 an "elbow " was tapped into the upper end of the 

 of the radiator, and this being'open (upward) gave 

 an opening to the air. To ascertain the position of 

 the water, two air cocks were put in the radiator ; 

 one in the elbow and the other 6 inches lower in the 

 end of the radiator. When in position the appara- 

 tus was filled with water, through the elbow, till the 

 lower air-cock showed water. The entire system 

 was thus filled, with an air space or expansion 

 chamber in the top of the upper radiator. It was 

 thought this would all be needed, but in practice 

 only about three inches of space at the top of the 

 radiator was required. 



To understand the exact proportions of the 

 plant, it may be mentioned that the boiler had 

 about 5 square feet of heating surface and held 2i 

 gallons of water. The lower radiator held 2.8 gal- 

 lons of water and gave 21 square feet of radiating 

 surface. The upper radiator had a capacity of 3.5 

 gallons, and gave 28 square feet of radiating sur- 

 face. The flow and return pipes in the kitchen also 

 held water and gave about 5 square feet of surface. 

 The totals were about g gallons of water and 54 

 square feet of available heating surface in the two 

 rooms. 



