Online Encyclopedia
Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.
HEATING
Online EncyclopediaEncyclopedia Home :: HAN-HEG
del.icio.us it!
|
HEATING . In temperate latitudes the See also:climate is generally such as to necessitate in dwellings during a See also:great portion of the See also:year a temperature warmer than that out of doors. The See also:object of the See also:art of heating is to secure this required warmth with the greatest See also:economy and efficiency. For reasons of See also:health it may be assumed that no See also:system of heating is advisable which does not provide for a See also:constant renewal of the See also:air in the locality warmed, and on this See also:account there is a difficulty in treating as See also:separate matters the subjects of heating and See also:ventilation, which in See also:practical schemes should be considered conjointly. (See VENTILATION). The object of all heating apparatus is the transference of See also:heat from the See also:fire to the various parts of the See also:building it is intended to warm, and this See also:transfer may be effected by See also:radiation, by See also:conduction or by convection. An open fire acts by radiation; it warms the air in a See also:room by first warming the walls, See also:floor, See also:ceiling and articles in the room, and these in turn warm the air. There-fore in a room with an open fire the air is, as a See also:rule, less heated than the walls. In many forms of fireplaces fresh air is brought in and passed around the back and sides of the See also:stove before being admitted into the room. A closed stove acts mainly by convection; though when heated to a high temperature it gives out radiant heat. Windows have a chilling effect on a room, and in calculations extra See also:allowance should be made for window areas. There are a number of methods available for See also:adoption in the heating of buildings, but it is a See also:matter of considerable difficulty to suit the method of warming to the class of building to be warmed. Heating may be effected by one of the following systems, or installations may be so arranged as to combine the advantages of more than one method: open fires, closed stoves, hot-air apparatus, hot See also:water circulating in pipes at See also:low or at high pressure, or See also:steam at high or low pressure. The open See also:grate still holds favour in See also:England, though in See also:America and on the See also:continent of See also:Europe it has been superseded by the closed stove. The old See also:form of open fire is certainly wasteful of See also:fuel, and the loss of heat up the See also:chimney and by conduction into the See also:brickwork backing of the stove is considerable. Great improvements, however, have been effected in the See also:design of open fireplaces, and many ingenious contrivances of this nature are now in the See also:market which combine efficiency of heating with economy of fuel. Unless suitable fresh air inlets are provided, this form of stove will cause the room to be draughty, the strong current of warm air up the flue See also:drawing See also:cold air in through the crevices in the doors and windows. The best form of open fireplace is the ventilating stove, in which fresh air is passed around the back and sides of the stove before being admitted through convenient openings into the room. This has immense advantages over the See also:ordinary type of fireplace. The illustrations show two forms of ventilating fireplace, one (fig. I) similar in See also:appearance to the ordinary domestic grate, the other (fig. 2) with descending See also:smoke flue suitable for hospitals and public rooms, where it might be fixed in the See also:middle of the apartment. The fixing o stoves of this See also:kind entails the laying of pipes or ducts from qua open to convey fresh air to the back of the stove. With closed stoves much less heat is wasted, and consequently less fuel is burned, than with open grates, but they often cause an unpleasant sensation of dryness in the air, and the products of See also:combustion also See also:escape to some extent, rendering this method of heating not only unpleasant but sometimes even dangerous. The method in Great See also:Britain is almost entirely confined to places of public See also:assembly, but in warn air America and on the continent of Europe it is much used for domestic heating. If the flue See also:pipe be carried up a considerable distance inside the apartment to be warmed before being turned into the See also:external air, practically the whole of the heat generated will be utilized. See also:Charcoal, See also:coke or See also:anthracite See also:coal are the fuels generally used in slow combustion heating stoves. See also:Gas fires, as a substitute for the open coal fire, have many points in their favour, for they are conducive to cleanliness, they need but little See also:attention, and the heat is easily controlled. a88 On the other See also:hand, they may give off unhealthy fires. fumes and produce unpleasant odours. They usually take the form of See also:cast See also:iron open stoves fitted with a number of See also:Bunsen burners which heat perforated lumps of See also:asbestos. The best form of stove is that with which perfect combustion is most nearly attained,. and to which a See also:pan of water is affixed to See also:supply a desirable humidity to the air, the gas having the effect of drying the See also:atmosphere. With another form of gas stove coke is used in See also:place of the perforated asbestos; the fire is started with the gas, which, when the coke is well alight, may be dispensed with, and the fire kept up with coke in the usual way. See also:Electrical heating appliances have only recently passed the experimental See also:stage; there is, however, undoubtedly a great future for electric heating, and the perfecting of the Blecl stove, together with the cheapening of the electric heatinlcag. current, may be expected to result in many of the other stoves and convectors being superseded. Hitherto the large See also:bill for electric See also:energy has debarred the See also:general use of electrical heating, in spite of its numerous advantages. See also:Oils are powerful fuels, but the high See also:price of refined See also:petroleum, the oil generally preferred, precludes its widespread use for many purposes for which it is suitable. In small stoves for warming and for cooking, petroleum presents some advantages over other fuels, in that there is no chimney to sweep, and if well managed no unpleasant fumes, and the stoves are easily portable. On the other hand, these stoves need a considerable amount of attention in filling, trimming and cleaning, and there is some See also:risk of See also:explosion and damage-by accidental leaking and smoking. Crude or unrefined petroleum needs a See also:special air-spray pressure burner for its use, and this suffers from the disadvantage of being noisy. Gas and oil radiators would be more properly termed `.` convectors," since they warm mainly by convected currents. They are similar in appearance to a hot-water or steam radiator, and, indeed, some are designed to be filled with water and used as such. They should always be fitted with a pan of water to supply the necessary humidity to the warmed air, and a flue to carry otl any disagreeable fumes. supply Smoke flue Cold ai Open fires. Closed stoves. on stoves. Heating by warmed air, one of the See also:oldest methods in use, generally See also:merge in a single return pipe which is connected to has been much improved by attention to the construction of the See also:lower See also:part of the See also:boiler. the apparatus, and if properly installed will give as The See also:rate of circulation in the ordinary low pressure hot-water w air. ar°' See also:good effects as it is possible to obtain. The system system may be considerably accelerated by means of steam is especially suitable for churches, assembly halls and injections. The water after being heated passes into a circulating large rooms. A stove of special design is placed in a chamber in the See also:basement or cellar, and cold fresh air is passed through it, and led by means of flues to the various apartments for See also:distribution by means of easily regulated inlet valves. To prevent the atmosphere from becoming unduly dry a pan of water is fitted to the stove; this serves to moisten the air before it passes into the distributing flues. If each distributing flue is connected by means of a mixing See also:valve with a cold-air flue, the warmth of the incoming air can be regulated to a nicety (see VENTILATION). There are many different systems of heating by hot water circulating in pipes. The oldest and best known is the " two See also:tow pipe " system, others being the " one pipe " or " See also:simple pressure See also:circuit," and the " drop " or " overhead." The high hot pressure system is of later invention, having been water. first put to practical use by A. M. See also:Perkins in 1845. All these methods warm chiefly by means of convected heat, the amount of true radiation from the pipes being small. The manner in which the circulation of hot water takes place in the tubes is as follows. Fire heats the water in a boiler from the See also:top of which a " flow " pipe communicates with the rooms to be warmed (fig. 3). As the water is heated it becomes lighter, rises to the top of the boiler, and passes along the flow cold See also:mat¢r pipe. It is followed by O o,f,,,,, ~ ~~ haaae Cisf¢re more and more hot water, Combined feed & ® and so travels along the flow ppans,on took I pipe, which is rising all the See also:time, to the farthest point of the circuit, by which time it has in all See also:probability cooled considerably. From this point the " re- $ ~"~ R' turn " pipe drops, usually at 1e mlrr¢fnni the same rate as the flow pipe rises; and in due course the water reaches its starting point, the boiler, and is again heated and again cir- /~~ern, y f culated through the system. The connexion of the return pipe is made with the lower part of the boiler. Branches R 1/~ a may be made from the See also:main pipes by means of smaller pipes arranged in the same manner as the mains, the 'Mau, retcr,- P Pe Boiler See also:branch flow pipe being See also:con- R. denotes radator See also:rap t° empty system nected with the main flow v. regulating value TN pipe and returning into the main return. To obtain a larger heating See also:surface than a pipe affords, radiators are connected with the pipes where desired, and the water passing through them warms the sur- rounding air. The " one pipe " system (fig. 4) acts on precisely the same principle, but in place of two pipes being placed in adjacent positions one large main makes a See also:complete circuit of the See also:area to be warmed, starting from and returning to the boiler, and from this main flow and return branches are taken and connected with radiators and other heating appliances. In the " drop " or " overhead " system (fig. 5) a rising main is taken directly from the boiler to the topmost floor of the building, and from this branches are dropped to the lower floors, and connected by means of smaller branches to radiators or coils. The See also:vertical branches descend to the basement and Stopcock Bross *R. tank into which steam is introduced; this, mixing with the hot water, gives it additional See also:motive See also:power, resulting in a faster circulation. This steam condensing adds to the water in the pipe and naturally causes an overflow, which is led back to the boiler and re-used. In districts where the water is hard, this arrangement considerably lengthens the See also:life of the boiler, as the same water is used over and over again, and no fresh See also:deposit of See also:fur occurs. Owing to the very rapid See also:movement and the consequent increased rate of transmission of heat, the pipes and radiators may be reduced in See also:size, in many circumstances a very desirable thing to achieve. With this system the temperature eh floor v. v. R. R. 11111111 v. v. -See also:Im Alternative method with separate return pipe v. v. R. R. R. denotes radiator V. „ regulating value Boiler Tap to,, empty + system R. R. R. p. a can be quickly raised and easily controlled. If the See also:weather is mild, a moderate heat may be obtained by using the apparatus as an ordinary hot water system, and shutting off the steam injectors. The cold-water supply and expansion tank (fig. 3) are often combined in one tank placed at a point above the level of circulation. The tank should be of a size to hold not less than a twentieth part of the See also:total amount of water held in the system. The automatic inlet of cold water to the hot water system from the main See also:house tank or other source is controlled by a See also:ball valve, which is so fixed as to allow the water to rise no more than an See also:inch above the bottom of the tank, thus leavin^ the See also:remainder of the space clear for expansion. An overflow is provided, discharging into the open air to allow the water to escape should the ball valve become defective. The " Perkins " or " small See also:bore high pressure " system (fig. 6) has many advantages, for it is safe, the boiler is small High and is easily managed, the temperature is well under pressure See also:control and may be regulated to suit the changing hot weather, and the small pipes See also:present a neat appearance water. in a room. The whole system is constructed of wrought iron pipe of small See also:diameter, strong enough to resist a testing pressure of 2000 to 2500 lb per,sq. in. The boiler consists of similar pipe coiled up to form a fire-See also:box, inside which the See also:furnace is lighted. The coil is encased with firebricks and brickwork, and the smoke from the fire is carried TCold eater off by a flue in the ordinary euP ls5 o way. The flow pipe of similar :See also:rank of orate. See also:section (usually having an ;treated by *oil See also:internal diameter of about i in., the See also:metal being nearly 4 in. thick) continues from the top of the coil, and after travel-See also:ling See also:round the various apartments returns to, and is connected with, the lowest part of the boiler coil. The See also:joints take a special form to enable them to withstand the great See also:strain to which they are subjected (fig. 7). One end of a pipe is finished See also:flat, the end of the other pipe being brought to a conical edge. On one end also a right-handed, and on the other a See also:left-handed, See also:screw-See also:thread is turned. A coupling See also:collar, tapped in the same manner, is screwed on, and causes the conical edge to impress itself tightly on the flat end, giving a See also:sound and lasting See also:joint. The system is hermetically sealed after being pumped full of water, an expansion chamber in the shape of a pipe of larger dimensions being provided at the top of the system above the highest point of circulation. Upon the application of heat to the fire-box coil the water naturally expands and forces its way up into the expansion chamber; but there it encounters the pressure of the confined air, and ebullition is consequently prevented. Thus at no time can steam form in the system. This system is trustworthy and safe in working. The smallness of the pipes renders it liable to damage by See also:frost, but this See also:accident may be prevented by always keeping in frosty weather a small fire in the furnace. If this course is inconvenient, some liquid of low freezing-point, such as glycerine, may be mixed with the water. For large public buildings, factories, &c., heating by steam is generally adopted on account of the rapidity with which heat is available, and the great distance from the boiler at steam which warming is effected. In the See also:case of factories heating. the exhaust steam from the engines used for See also:driving the working machinery is made use of and forms the most economical method of heating possible. There are several different systems of heating by steam—low pressure, high pressure and minus pressure. In the low pressure two pipe system the flow pipe is carried to a sufficient height directly above the boiler to allow of its See also:gradual fall to a little beyond the most distant point at which connexion is to be made with the return pipe, which thence slopes towards the boiler. Branches are taken off the flow pipe, and after circulating through coils or radiators are connected with the return pipe. In a well-proportioned system the pressure need not exceed 2 or 3 lb per sq. in. for excellent results to be obtained. The one-pipe system is similar in principle, the pipe rising to its greatest height above the boiler and being then carried around as a single pipe falling all the while. It resembles in many points the one-pipe low pressure hot-water system. Radiators are fed directly from the main. Where, as in factories or workshops, there are already installed engines working at a high steam pressure, say i2o to i8o lb per sq. in., a portion of the steam generated in the boilers may be utilized for heating by the aid of a reducing valve. The steam is passed through the valve and emerges at the pressure required generally from 3 lb upwards. It is then used for one of the systems described above. High-pressure steam-heating, compared with the heating by low pressure, is little used. The principles are the same as those applied to low-pressure See also:work, but all fittings and appliances must, of course, be made to stand the higher strain to which they are subjected. The " minus pressure " steam system, sometimes termed " atmospheric " or " vacuum,” is of more See also:recent introduction than those just described. It is certainly the most scientific method of steam-heating, and heat can be made to travel a greater distance by its aid than by any other means. The heat of the pipes is great, but can be easily regulated. The system is economical in fuel, but needs skilled attendance to keep the appliances and fittings in See also:order. The steam is introduced into the pipes at about the pressure of the atmosphere, and is sucked through the system by means of a vacuum See also:pump, which at the same operation frees the pipes from air and from condensation water. This pumping See also:action results in an extremely rapid circulation of the heating See also:agent, enabling See also:long distances to be traversed without much loss of heat. Compared with heating by hot water, steam-heating requires less piping, which, further, may be of much smaller diameter to attain a similar result, because of the higher temperature of the heat yielding surface. A See also:drawback to the use of steam is the fact that the high temperature of the pipes and radiators attracts and spreads a great See also:deal of dust. There is also a risk that woodwork near the pipes may warp and split. The apparatus
needs constant attention, since neglect in stoking would result
in stopping the See also:generation of steam, and the whole system
would almost immediately cool. To regulate the heat it is
necessary either to instal a number of small radiators or to
See also:divide the radiators into sections, each section controlled by
distinct valves; steam may then be admitted to all the section
of the radiator or to any less number of sections as desired.
In a hot-water system the heat is given off at a lower temperature
and is consequently more agreeable than that yielded by a
steam-heating apparatus. The joint most commonly used for
hot-water pipes is termed the " See also:rust " joint, which is cheap to
make, but unfortunately is inefficient. The materials required
are iron borings, sal-ammoniac and See also:sulphur; these are mixed
together, moistened with water, and rammed into the socket,
which is previously See also:half filled with See also:yarn, well caulked. The
materials mixed with the iron borings cause them to rust into a
solid See also:mass, and in doing so a slight expansion takes place. On
i3
C. denotes radiating coil
V. „ regulating wits
this account it is necessary to exercise some skill in forming the joint, or the socket of the pipe will be split; See also:numbers of pipes are undoubtedly spoilt in this way. Suitable proportions of materials to form a rust joint are 90 parts by See also:weight of iron borings well mixed with 2 parts of See also:flowers of sulphur, and r part of powdered sal-ammoniac. Another joint, less rigid but sound and durable, is made with yarn aid See also: The amount of expansion increases as the temperature is raised; at 340° F. it is 22 in. in See also:loo ft. With wrought iron pipes bends may be arranged, as shown in fig. 8, to take up this expansion. With cast iron pipe this cannot be done, and no length of piping over 40 ft. should be without a proper expansion joint. The pipes are best supported on rollers which allow of movement without straining the joints. There are several joints in general use for the best class of work which are formed with the aid of See also:india-See also:rubber rings or collars, any expansion being divided amongst the whole number of joints. In the rubber See also:ring joint an india-rubber ring is used; slightly less in diameter than the pipe. The rubber is circular in section, and about z in. thick, and is stretched on the extreme end of a pipe which is then forced into the next socket. This joint is durable, secure and easily made; it allows for expansion and by its use the risk of pipe sockets being cracked is avoided. It is much used for greenhouse heating See also:works. See also:Richardson's patent joint (fig. 9) is a good form of this class of joint. The pipes have specially shaped ends between which a rubber collar is placed, the joint being held together by clips. The result is very satisfactory and will stand heavy water pressure. Messenger's joint (fig. 10) is designed to allow more freedom of expansion and at the same time to withstand considerable pressure; one loose cast iron collar is used, and another is formed as a socket on the end of the pipe itself. One end of each pipe is See also:plain, so that it may be cut to any desired length; ©, pipes with shaped ends obviously must be obtained in the exact lengths required. See also: Direct radiators are a development of the See also:early coil of pipe; they are made in various types and designs and are usually of cast iron. Ventilating radiators are similar, but have an inlet arrangement at the See also:base to allow external air to pass over the heating surface before passing out through the perforations. Radiators should not be fixed directly on to the main heating pipe, but always on branches of smaller diameter leading from the flow pipe to one end of the radiator and back to the main return pipe from the other end; they may then be easily controlled by a valve placed on the branch from the flow pipe. To each radiator should be fitted an air tap, which when opened will permit the escape of any air that has accumulated in the coil; otherwise See also:free circulation is impossible, and the full benefit of the heat is not obtained. A plentiful supply of hot water is a See also:necessity in every house for domestic and hygienic purposes. In small houses all requirements may be satisfied with a boiler heated by the See also:kitchen fire. For large buildings where large quantities of hot water are used an See also:independent boiler of suitable size should be installed. Every See also:installation is made up of a boiler or other water heater, a tank or See also:cylinder to contain the water when heated, and a cistern of cold water, the supply from which to the system is regulated automatically by a ball valve. These containers, proportioned to the required supply of hot water, are connected with each other by means of pipes, a " flow " and a " return " connecting the boiler with the cylinder or tank (fig. 12). The flow pipe starts from the top of the boiler and is connected near the top of the cylinder, the return pipe joining the lower portions of the cylinder and boiler. The supply from the cold water cistern enters the bottom of the cylinder, and thence travels by way of the re-turn pipe to the boiler, where it is heated, and back through the flow pipe to the cylinder, which is thus soon filled with hot water. A flow pipe which serves also for expansion is taken from the top of the cylinder to a point above the cold - water supply and turned down to prevent the See also:ingress of dirt. From this pipe at various points are taken the supply pipes to See also:baths, lavatories, sinks and other appliances. It will be observed that in fig. 12 the cylinder is placed in proximity to the boiler; this is the usual and most effective method, but it may be placed some distance away if desired. The tank system is of much earlier date than this cylinder system, and although the two resemble each other in many respects, the tank system is in practice the less effective. The tank is placed above the level of the topmost draw off, and often in a See also:cupboard which it will warm sufficiently to permit of its being used as a See also:linen airing closet. An expansion pipe is taken from the top of the tank to a point above the roof. All draw off services are taken off from the flow pipe which connectg. the boiler with the tank. This method differs from that adopted in the cylinder system, where all services are led from the top of the cylinder. A suitable proportion between the size of the tank or cylinder and that of the boiler is 8 or 10 to I. Water may also be heated by placing a coil of steam or high-pressure hot-water pipes in a water tank (fig. 6), the water heated in this way circulating in the manner already described. An alternative See also:plan is to pass the water through pipes placed in a steam See also:chest.
Cylinders, tanks and independent boilers should be encased in a non-conducting material such as silicate See also:cotton, thick See also:felt or asbestos See also:composition. The two first mentioned are affixed
for pipes. heated to this temperature about 12 in., an amount
Hot-water supply.
See also: The size of the boiler may be increased or diminished by the addition or subtraction of one or more sections; these, being simple in design, are easily fitted together, and should a section become defective it is a simple matter to insert a new one in its place. Should a defect occur with a wrought iron boiler it is usually necessary for the purpose of repair to disconnect and remove the whole apparatus, the heating system of which it forms a part being in the meantime useless. In a type built with vertical sections each See also:division is complete in itself, and is not directly connected with the next section, but communicates with flow and return drums. A defective section may thus be left in position and stopped off by means of plugs from the Fu ei"ay drums until it is convenient to See also:fit a new 14, one in its place. A boiler with horizontal sections is shown in fig. 15; it will be seen that each of the upper sections has a number of See also:cross waterways which form a See also:series of gratings over the fire-box and intercept most of the heat generated, effecting great economy of fuel. In the ordinary working of a hot-water apparatus the expansion pipe already referred to will prevent any overdue pressure occurring in the boiler; should, however, the pipes Safety valves. become blocked in any way while the apparatus is in use, or the water in them become frozen, the See also:lighting of the fire would cause the water to expand, and having no outlet it would in all probability burst the boiler. To prevent this a safety valve should be fitted on the top of the boiler, or be connected thereto with a large pipe so as to be visible. The valve may be of the dead weight (fig. 16), See also:lever weight, See also:spring (fig. 17) or See also:diaphragm variety. The three first named are largely used. In the diaphragm valve a thin piece of metal is fixed to an outlet from the boiler, and when a moderate pressure is exceeded this gives way, allowing the water and steam to escape. Fusible plugs are little used; they consist of 'pieces of softermetal inserted on the See also:side of the boiler, which melt should the heat of the water rise above a certain temperature. A " See also:Geyser " is a very convenient form of apparatus for heating a quantity of water in a See also:short time. A water pipe of See also:copper or wrought iron is passed through a cylinder in which Geysers. gas or oil heating burners are placed. The piping takes a winding or zigzag course, and by the time the outlet is reached, the water it contains has reached a high temperature. By this means a continuous stream of hot water is obtained, greater or smaller in proportion to the size and power of the apparatus. The improved types of gas geysers are provided with a single control to both gas and water supplies, with a small " See also:pilot " burner to ignite the gas. A flue should in all cases be provided to carry off the fumes of the fuel. In districts where the water is of a " hard nature," that is, contains bicarbonate of See also:lime in See also:solution, the interior of the boiler, cylinders, tanks and pipes of a hot water system will become incrusted with a deposit of lime which is gradually precipitated as the water is heated to boiling point. With " very hard " water this deposit may require removal every three months; in See also:London it is usual to clean out the boiler every six months and the cylinders and tanks at longer intervals. For this purpose manlids must be provided (See also:figs. 13 and 14), and pipes should be fitted with removable caps at the bends to allow for periodical cleaning. The lime deposit or " fur " is a poor conductor of heat, and it is therefore most detrimental to the efficiency of the system to allow the interior of the boiler or any other portion to become furred up. Further, if not removed, the fur will in a short time bring about a fracture in the boiler. The use of soft water entails a disadvantage of another See also:character—that of corroding iron and lead work, soft water ezereisiirg a very vigorous chemical action by means of bands or straps or stitched on; the asbestos is laid on in the form of a See also:plaster from 2 to 6 in. thick. Taps to baths and lavatories should be connected to the main services by a flow and return pipe so that hot water is constantly flowing past the tap, thus enabling hot water to be obtained immediately. Frequently a single pipe is led to the tap, but the water in this branch cools and must therefore be See also:drawn off before hot water can be obtained. Two classes of boilers are chiefly used in hot-water heating installations, viz. those heated by the fire of the kitchen range, Boilers. and those heated separately or independently. Of the first class there are two varieties in See also:common use— a form of " saddle " boiler (fig. 13) and the " See also:boot " boiler (fig. 14). Independent boilers are made in every conceivable size and form of construction, and many of incrustation. upon these metals. In districts supplied with soft water, copper should be employed to as large an extent as possible. The table given below will be useful in calculating the size of the radiating surface necessary to raise the temperature to the extent required when the external air is at freezing point (32° Fahr.): In closing this account of heating and the practical methods of application of heat, an example may be mentioned to show the great capabilities of a carefully planned system. steam at At the See also:city of See also:Lockport in New See also:York See also:state, America, Lockport, an interesting example of the direct application of steam-heating on a large See also:scale has been carried out under the direction of Mr Birdsill See also:Holly of that city. Houses within a See also:radius of 3 M. from the boiler house are supplied with superheated steam at a pressure of 35 lb to the in. The mains, the largest of which are 4 in. in diameter, and the smallest 2 in., are wrapped in asbestos, felt and other non-conducting materials, and are placed in wooden tubes laid under ground like water and gas pipes. The house branches pipes are 12 in. in diameter, and pipes are used inside the houses. The steam is employed for warming apartments by means of pipe radiators, for heating water by steam injections, and for all cooking purposes. The steam mains to the houses are laid by the supply See also:company; the internal pipes and fittings are paid for or rented by the occupier, costing for an installation from 30 for an ordinary eight-roomed house to £loo or more for larger buildings. With the success of this undertaking in view it is a matter of wonder that the example set in this instance has not been adopted to a much greater extent elsewhere. The See also:principal publications on heating are: See also:Hood, Practical See also:Treatise on Warming Buildings by Hot Water; See also:Baldwin, Hot Water Heating and Fittings; Baldwin, Steam Heating for Buildings; Billings, Ventilation and Heating; See also:Carpenter, Heating and Ventilating Buildings; Jones, Heating by Hot Water, Ventilation and Hot Water Supply; Dye, Hot Water Supply. U. Additional information and CommentsThere are no comments yet for this article.
» Add information or comments to this article.
Please link directly to this article:
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML. Site content, images, and layout Copyright © 2006 - Net Industries, worldwide. |
|
|
[back] HEATHFIELD, GEORGE AUGUSTUS ELIOTT, BARON (r717-179... |
[next] HEAVEN (0. Eng. hefen, heofon, heofone; this word a... |