67. ADJUSTING THE DAMPERS.--To get the best results from a cook stove, and at the same time overcome the wasting of fuel, the ways in which to adjust the dampers should be fully known. If it is desired to heat the oven for baking, close dampers f and i and open dampers g and h. With the dampers so arranged, the heated air above the fire is forced around the oven and up the flue, as is clearly shown by the arrows in Fig. 3. A study of this diagram will readily show that the lower left-hand corner of the oven is its coolest part, since the heated air does not reach this place directly, and that the top center is the hottest part, because the hottest air passes directly over this portion of the oven and the heated air in the oven rises to it.
If it is desired to heat the surface of the stove, so that cooking may be done on top of it, close dampers f, h, and i and open damper g. With the dampers so arranged, the heated air does not pass around the oven, but is confined in the space above it and the firebox, as shown in Fig. 4. While the damper i in the flue is closed in order to confine the heated air as much as possible to the space under the top of the stove, it contains openings that allow just enough air to pass up the flue to maintain the draft necessary for combustion. When the dampers are arranged as mentioned, the hottest place on the surface of the stove is between the firebox and the stovepipe, and the coolest place is behind the damper h.
68. BANKING A COAL FIRE.--To economize in the use of fuel, as well as to save the labor involved in building a new fire, it is advisable to keep a fire burning low from one meal to another and from one day to the next. As the nature of hard coal is such that it will hold fire for a long time, this can be done by what is called banking the fire. To achieve this, after the fire has served to cook a meal, shake the ashes out of the grate so that the glowing coals are left. Then put fresh coal on this bed of coals, and, with the dampers arranged as for building a new fire, allow the coal to burn well for a short time. Finally, cover the fire with a layer of fine coal and adjust the dampers properly; that is, close dampers g and h and open dampers f and i. If the banking is carefully done the fire should last 8 or 10 hours without further attention. Care should be taken, however, to use sufficient coal in banking the fire, so that when it is to be used again the coal will not be completely burned, but enough burning coals will remain to ignite a fresh supply. When the fire is to be used again, rake it slightly, put a thin layer of coal over the top, and arrange the dampers as for starting a fire. As soon as this layer of coal has begun to burn, add more until the fire is in good condition.
GAS STOVES AND THEIR OPERATION
69. GAS RANGES.--A gas stove for cooking, or gas range, as it is frequently called, consists of an oven, a broiler, and several burners over which are plates to hold pans, pots, and kettles in which food is to be cooked. As is true of a coal range, a gas range also requires a flue to carry off the products of unburned gas. Gas stoves, or ranges, are of many makes, but in principle all of them are practically the same; in fact, the chief difference lies in the location or arrangement of the oven, broiler, and burners. In Fig. 5 is illustrated a simple type of gas range. The oven a of this stove is located above the top of the stove, instead of below it, as in some stoves. An oven so located is of advantage in that it saves stooping or bending over. The door of this oven contains a glass, which makes it possible to observe the food baking inside without opening the door and thereby losing heat. The broiler b, which may also be used as a toaster, is located directly beneath the oven, and to the right are the burners c for cooking. The gas for these parts is contained in the pipe d, which is connected to a pipe joined to the gas main in the street. To get heat for cooking it is simply necessary to turn on the stop-cocks and light the gas. The four burners are controlled by the stop-cocks e, and the oven and the broiler by the stop-cock f. The stove is also equipped with a simmering burner for the slow methods of cooking on top of the stove, gas to this burner being controlled by the stop-cock g. To catch anything that may be spilled in cooking, there is a removable metal or enamel sheet h. Such a sheet is a great advantage, as it aids considerably in keeping the stove clean.
70. Some gas stoves are provided with a pilot, which is a tiny flame of gas that is controlled by a button on the gas pipe to which the stop-cocks are attached. The pilot is kept lighted, and when it is desired to light a burner, pressing the button causes the flame to shoot near enough to each burner to ignite the gas. However, whether the burners are lighted in this way or by applying a lighted match, they should never be lighted until heat is required; likewise, in order to save gas, they should be turned off as soon as the cooking is completed.
To produce the best results, the flame given off by gas should be blue. A flame that is yellow and a burner that makes a noise when lighted, indicate that the gas flame has caught in the pipe, and to remedy this the gas must be turned out and relighted. When the gas flame coming from a new burner is yellow, it may be taken for granted that not enough air is being admitted to make the proper mixture. To permit of the proper mixture, each gas pipe extending from the stop-cock and terminating in the burner is provided with what is called a mixer. This device, as shown in Fig. 6, consists of several slots that may be opened or closed by turning part a, thus making it a simple matter to admit the right amount of air to produce the desired blue flame. If burners that have been in use for some time give off a yellow flame, it is probable that the trouble is caused by a deposit of soot or burned material. Such burners should be removed, boiled in a solution of washing soda or lye until the holes in the top are thoroughly cleaned, and then replaced and adjusted. As long as the flame remains yellow, the gas is not giving off as much heat as it should produce and is liable to smoke cooking utensils black. Therefore, to get the best results the burners should be thoroughly cleaned every now and then in the manner mentioned. Likewise, the pan beneath the burners, which may be removed, should be cleaned very frequently, and the entire stove should be wiped each time it is used, for the better such a stove is taken care of, the better will it continue to do its work.