This section is from the book "The Principles And Practice Of Modern House-Construction", by G. Lister Sutcliffe. Also available from Amazon: How Your House Works: A Visual Guide to Understanding & Maintaining Your Home.
That the gas-stove is now so largely and so successfully used, is probably due more to Mr. Fletcher of Warrington than to anyone else. He made the subject of heating by gas a special study, and perfected the use of the atmos-phtfifl burner for this particular purpose. It seems a very simple matter to remve the coal from an ordinary fire-grate, attach a small casting provided with a number of holes and an atmospheric burner, and fill the grate with asbestos balls. This, however, is probably the most extravagant method of using gas for heating purposes. The grate is not designed for the purpose, and is much too deep to give the best results; it will probably require the addition of firebrick inside at the back to diminish its area, and the register must be closed to a very considerable extent, or the chief part of the heat will be lost. If one of the ordinary fittings is used, such as that shown in Fig. 477, it will probably be found that, if the atmospheric burner BE turned down, the gas will produce an unpleasant humming noise; this can only be obviated by either turning the gas partially off at the meter, and so throttling and reducing the pressure, or by using a special valve near the meter, snob as Stott's Gas -regulator, set for the- pressure most suitable for the stove. No. atmospheric burner can be made absolutely silent, but if the stove is desired for use in the chamber of an invalid, special attention should be paid to the choice of the most silent burner possible.
Too much stress cannot be laid on the necessity for a flue. Wherever a gas-stove is used, the products of combustion must not be allowed to enter the room. A mere hole through the wall, with the Hue of the stove put through it. is worse than useless, as the draught in such a ease is always inwards.
For economy in the consumption of gas a special gas-stove must be used, and of these stoves there are a great number of patterns. If the greatest possible radiant heat be desired, with the appearance of an open fire, the iron fret front should be chosen; the flames of the burners play upon the thin iron, and speedily heat it to redness. The incandescent-bal] lire comes next in radiating power. If, however, it be desired to turn the gas low, then a fibrous asbestos front should be used, as with tintype the gas-supply may be lessened to a greater extent than with any other.
Fig. 478 represents a stove suitable for placing in front of an ordinary register stove: it has an iron fret front 16 inches wide, and would be suitable for a bedroom about 20 feet square. The same kind of grate can be used with the ball-fuel, or with the fibrous asbestos.
In order to get the greatest value from the heat generated by the gas, it is desirable to pass the products of combustion around the inside of the grate before allowing them to escape to the flue. Such an arrangement is shown in Fig. 479, which represents a gas-stove made by Messrs Fletcher, Russell, & Co., Ltd. It will be seen that the waste gases pass up and down inside special passages in the exterior casing before reaching the Hue; the casing of the stove therefore gives off a great deal of heat. Such a stove requires a good flue, and a ⅜-inch gas-pipe. It measures 31½ inches high, 24½ inches wide, and 7.½ inches from back to front, and is calculated to warm rooms up to 20 feet square.
Fig 477. - Burner for Ashestos -lump Fire in ordinary Fire grate.
Fig. 478 -View of Gas stove with Iron Fret Front.
Another form of stove by the same makers, of which a view and vertical section are given in Fig. 480, is known as Fletcher's Tubular Stove, and gives both light and heat. The cold-air inlet may, if desired, be connected to a pipe carried through the external wall, or the stove may simply be placed in the room; in the latter case a circulation of the air in the room will be set up, the colder air passing in at the bottom, rising through the tubes, and coming out through the grating at the top. The flue must be connected to the chimney-flue, and it may be well to point out that in every case the inlet to the chimney-flue must be stopped by a plate, except where the stove-pipe passes through, otherwise the proper draught will not be obtained. My experience is that, with stoves of this type, it is essential to place a vessel of water on or near them, in order to moisten the air, otherwise it becomes unpleasantly dry. This type of stove is also made with the openings for the air in the front, the tubes being placed horizontally over the burners from front to back of the stove; the fresh air can be drawn from outside if de-sired.
The products of comlm-tion of gas consist of water. carbonic acid gases (dioxide and monoxide), sulphur dioxide, and other gases, depending upon the impurities in the gas. Stoves are made which are called "condensing stoves", and which depend upon the cooling action of certain surfaces; the vapour of water produced by the combustion is deposited in the form of drops upon these surfaces, and the water takes up the sulphur dioxide, forming sulphurous acid, and falls down into a special receptacle, which needs emptying frequently. The objectionable smell, usually emitted by a gas-stove unprovided with a flue, is done away with, but the invisible and injurious carbonic acid gases are unaffected and are therefore given off. For this reason, I consider that no gas-stove, whether of the condensing type or any other, should be used without a flue, if proper attention to health is given. The general public appear to believe that a "condensing stove" does away with all the products of combustion, but this is an entire delusion. It may, however, be considered that a condensing stove is of no greater detriment to the air of a room than the ordinary gas-burner, used without either special inlet-flue or outlet-Hue for the air. This is of course true, but it must be remembered that a stove may consume a far larger quantity of gas than a number of burners; it is also upon the floor, and the heated carbonic acid gas rises easily to the breathing level, whereas, in the case of gas for illuminating purposes, the foul gases are often carried off through the ventilating outlets, which may be near the ceiling
Fig . 479 - section of Gas-stove with Flue ,for U tilizing the waste Heat.
Fig. 480 - View and vertical section of Tubular Gas-stive.
Another form of condensing stove, known as Clark's "Syphon" Hygienic Condensing Gas-stove, is illustrated in Fig. 481. It consists of two Argand burners with the usual chimney tubes, and the particular type illustrated is stated to consume 16 feet of gas per hour, when turned full on, and to heat a room about 18 feet by 18 feet. Below the stove itself is the drip-tray, into which the water falls, as it is condensed. I cannot lay too much stress upon the fact that, although the greater part of the objectionable odour proceeding from the gas-stove without a flue is done away with, yet the large volume of carbonic acid gas is delivered into the room. This stove is intended to be used without a special flue, and some of the advantages claimed for it by the makers are that no flue is required, that no smoke, smell, or dirt, is produced. By the use of a water-vessel, the air can be rendered moist if desired. In passing. I may remark that it is especially desirable in a sick-room, where the patient is suffering from bronchitis, asthma, or other troubles of the respiratory organs, that the air should be moist, and it is usually better to make use of a wet blanket placed over a chair near the fire, than of a special kettle; the moisture will pass from the blanket readily in the form of vapour.
Fig. 481 - "Syphon" condensing Gas-stove.
Flat Stoves have also been specially designed for use under floor-gratings, and one <>f these is illustrated in Fig. 482. The same remark applies to such stoves as to those already described, that, unless the products of combustion are carried away by a special flue, they will be found very objectionable.
Fig. 482 - Flat Gas-stove for flxing under Floors.
Where gas cannot be had from a public supply, oil-stoves are often useful; but the price of oil has now risen so much higher than it was some years ago, that it will be found in most cases much more economical to use coal for permanent work, but where portability is an advantage, the oil-stove has many points in its favour. There are now several very satisfactory stoves upon the market, among which we may mention those known as Rippingille's. The type of burner has recently been improved, and now the flat wick is used instead of the circular. In Fig. 483 is shown a large type, known as the "Emperor". The oil-tank is of cast-iron in one piece, and is fitted with two 6-inch burners with patent extinguishers, in separate cylinders; the frames and radiators are of cast-iron, with large mica windows. The stoves are also made with very ornamental east iron cases. The same remarks apply to the use of oil-stoves as I have already made with regard to gas-stoves, except that the sulphurous acid fames are not present. but it is obvious that where so powerful a burner is used without a Hue. the amount of carbonic acid gas given off must he very considerable.
Fig. 483 - The "Emperor" Oil-stove.
A type of so-called condensing-stove is also made for burning oil. and, of course, the same method of adding moisture to the heated air can be adopted as was described in connection with the gas-stoves.