One advantage possessed by steam cooking is that the kitchen does not become over heated, as the boiler, if desired, can be placed in a basement or elsewhere, provided it is convenient for stoking; and there is, of course, economy of space.
Steam can be economically used for every description of cooking purpose, and for heating water, by placing a coil of steam pipe in the water that is to be heated.
78. Steam Boiler.
Fig. 78 represents a steam boiler which requires to be fixed in brickwork. They are also made cylindrical (vertical) in shape with the furnace within them, and so require no setting, except connection with the chimney. A description of a steam boiler will be found under “motors,” the boiler and fittings in each case being nearly identical, except that a pressure-gauge is not always used with a boiler for cooking purposes, and a different means is provided for water supply generally, as illustrated. The reference letters indicate:—a, inlet valve, regulated by stone float c and balance-weight h; b, cold supply-pipe from main; d, safety-valve; e, water gauge; f, steam delivery pipe; g, manlids.
In many instances, especially when the boiler is in a kitchen range, a steam chest is used. This is a square wrought-iron box, of nearly the same capacity as the boiler, and situated somewhere near but in a more conveniently accessible position.
All the fittings are attached to this chest, which is connected to the boiler by 2 pipes one above and one below water level (2 pipes being necessary to equalise the pressure). The chest is of service when the boiler is not easily accessible, as the fittings should always be situated where they can have regular attention, cleaning, &c., and it is very necessary to see that the water inlet valve and safety valve are in proper working order.
Sometimes in small steam boilers in kitchen ranges the inlet valve is dispensed with, and an ordinary cast-iron supply cistern is used, with a ball valve in the usual way; but the cistern must have a lid that can be secured, and the pipe between the cistern and boiler must have a deep syphon to prevent the water being blown back by the steam. This system, however, cannot be recommended, as it is not reliable. When this system is adopted it is generally where the boiler is also used for hot-water supply, and only when comparatively no pressure of steam is required for 1-3 small kettles. See also p. [1004].
Gas.—Gas cooking stoves are now growing in favour, as being very convenient and cleanly, instantaneously lighted and extinguished, and producing no smoke, soot, or ashes. They are portable, and the cost of fixing is generally small; but, as with all gas contrivances, they can only be adopted where gas is to be obtained. The makers claim economy over coal-burning ranges, greater simplicity in working and cleaning, less attention, unvarying heat, &c. There are, however, drawbacks in not having means of working a high-pressure boiler for bath supply, &c. (this, however, is now being overcome), and there are sometimes complaints of waste of gas, as servants cannot always be relied upon to turn off or lower the gas at intervals when it is not required.
Gas ranges have now attained a high degree of perfection, and the results are very satisfactory. There is no obnoxious taste commonly associated with meat cooked by this means, and it has been proved that no difference can be discerned even by the most fastidious between joints cooked in gas and coal-burning ranges. Gas ranges are made in numberless sizes and shapes to meet every requirement, from the small “Workman’s Friend,” which is large enough to cook a steak and boil a quart of water, to those that are used in large institutions, hospitals, &c., to cook for hundreds daily.