Air conditioning

“ A specialized engineering field has recently developed, technically known as air conditioning, or the artificial regulation of atmospheric moisture. The application of this new art to many varied industries has been demonstrated to be of greatest economic importance. ”

“ To ensure that installed air conditioning and heating systems operate at maximum rated efficiency levels, the Secretary shall, not later than 180 days after the date of enactment of this subsection, carry out a program to educate homeowners and small business owners concerning the energy savings from properly conducted maintenance of air conditioning, heating, and ventilating systems. ”

“ Look inside a VDT and you’ll very likely find an orange glow in the neck of the tube. The heat there may be no more than a light bulb’s, but on a hot day, with more than one machine in the same room, you’ll want your air conditioning to be up to the job. ”

“ STANDARDS FOR SINGLE PACKAGE VERTICAL AIR CONDITIONERS AND HEAT PUMPS. (a) Definitions— Section 340 of the Energy Policy and Conservation Act (42 U.S.C. 6311) is amended by adding at the end the following: ' (22) SINGLE PACKAGE VERTICAL AIR CONDITIONER- The term 'single package vertical air conditioner' means air-cooled commercial package air conditioning and heating equipment that— ' (A) is factory-assembled as a single package that— ' (i) has major components that are arranged vertically; ' (ii) is an encased combination of cooling and optional heating components ”

“ It is now being more generally recognised in this country that the ventilation and the heating of a building should be kept separate and distinct, and that the fresh air warming arrangements should be independent of those employed for heating. ”

“ I had hoped to have time to discuss the subject of heating more fully in connection with ventilation, but cannot; but I will state, in the simplest manner, a few of the leading points first.
You must have fresh air all the time. In summer you can get it by opening the doors and windows. In winter it must be warmed before entering the room. It must not enter the room cold and flow across the floor to the other side before it reaches the heating apparatus. ”

“ The leading idea should be to give the most advantageous direction to the natural currents of air. Systematic supply of fresh air, combined in some form with the heating apparatus, is appropriate in many cases, particularly as it permits some control over the purity, temperature and humidity of the air entering the building.
Mechanical or forced ventilation finds application where the number of people, excess of heat, or other conditions creating unwholesome atmosphere, can not be overcome by any other method. ”

“ From the earliest times in the latitudes of northern Europe and North America, some form of heating in cold weather has been a necessity for all buildings, whether caves or palaces, but even as late as the latter part of the nineteenth century such a thing as a uniform temperature in heated rooms in severe weather was never expected, while ventilation was invariably secured only by such means as would be accomplished by the circulation of air through doors and other openings. ”

“ If we can give to our houses an average temperature of 55° with local exceptions somewhat in excess of this average, we make them, and particularly the lofty slip of building forming the common London street-house, into a warm air-shaft, having an upward draught. If we can properly arrange and control the entrances and exits of the necessary air, and secure that the supply be ample and the conditions of its motion innocuous, we have solved the problem of practical ventilation. ”

“ The velocity of the incoming air is between 1 and 2 ft. per second. The driving fan in the basement sends air into the building at the rate of 1059 cub. ft. per head per hour by means of electricity. The temperature in different parts of the house can be observed in a central control office, and here also are the levers which control the valves regulating the air supply, both hot and cold. During a performance the superintendent of heating and ventilation is on duty in this office and secures to each part of the building its proper supply of fresh air at a proper temperature. ”

“ The systems which may be employed for mechanical ventilation are numerous and varied, but they all embody the use of fans of one kind or another for forcing the air into the rooms, or exhausting it, or both, with proper provision for heating the incoming air in cold weather, and some one of the three heating systems is frequently, if not generally, employed in connection with a system of mechanical ventilation. ”

“ The higher temperature in an occupied building—particularly in cold weather, when doors and windows are kept closed to exclude draughts—combined with the ascensional movement of the heated air arising from the lungs and body, are also utilised as powerful and never-failing auxiliaries in changing the air and inducing an inward and upward current, even when there is absolutely no perceptible movement of the air outside. ”

“ In the days of our forefathers, when houses were built with large rooms and great, high-ceiling halls, and when people spent a large part of their time in the open, air, there was in reality but little need of artificial ventilation ”

“ In such cases, and especially where a large amount of ventilation is desired, it is necessary to see that the quantity , as obtained above, is equal to the amount of air required for ventilation. It will be found sufficient in all ordinary cases to change the air four times per hour, which is generally satisfactory for private houses; but where much entertaining is to be allowed for, six times per hour is better. ”

“ This means quick and positive venting for steam, vapor, or hot water installations and provides rapid circulation, causes radiator to heat up more rapidly.
Air Vent (Steam heating)
The air vent on each main, allows the air to escape so that the heat arrives more rapidly to radiator. This of course, saves fuel.
Heat Controls
To take the heating of your home out of the area of dreams and out of the expensive realm of “feeling,” some sort of heat regulating device is recommended. It is foolish to say “Do you think it is warm enough?” to a group in the room. For no two will think alike! ”

“ Now, to apply these principles to every-day life, to the heating and ventilation of our houses, taking the open fire first, we find that it acts like the sun, heating exclusively by direct radiation. The rays of heat fall upon the sides of the room, the floor and ceiling, and the solid substances in the room, which thus become partially heated, and in their turn become secondary radiators. This radiant heat from the fire does not heat the air in the room at all, but the air becomes partially warmed by coming in immediate contact with the sides of the room, the furniture, &c. ”

“ Ventilation can render air even better than the outdoor variety by purifying it of dust and by supplying it with the right amount of moisture and motion.
For the ordinary home the great air conditioners and ozonators, which are installed in institutions and factories, are unnecessary, so we will not consider them. The best, simplest and least expensive ventilating system for the home is the system regulated by fans and blowers, and to this method we will introduce ourselves. ”

“ Ventilation and Heating.—The subject of the heating of our rooms and houses is very closely allied to that of ventilation, not only because both are a special necessity at the same time of the year, but also because we cannot heat a room without at the same time having to ventilate it by providing an egress for the products of combustion and introducing fresh air to replace the vitiated. ”

“ In a house thus warmed and free from draughts or blasts of cold air, ventilation becomes the simplest of problems. Nothing more is required than to provide an inlet and outlet in suitable places, and of suitable dimensions, when the difference between the specific gravity of the cold air without and warm air within does all the rest. Nothing is easier to arrange than to cause all the entering air to be warmed on its way by the hall stove, and to regulate the supply which each apartment shall receive from this general or main stream by adjusting its own upper outlet. ”

“ As the impelling force of the air current will be the difference between the weight of the cool column of air in the downcast shaft and roads and the warm column in the upcast, the available force of natural ventilation and cooling will increase just as demanded, i.e., it will increase with the depth of the workings and the heat of the rocks. ”

“ To secure ventilation in a hot climate with low buildings extending over a large area, and therefore incapable of being connected with any general system of ventilation, it was considered that forcing in fresh air by a small mechanical apparatus attached to each building would be the only effective means. ”

“ It combines the three great essentials necessary for comfort and health—warmth, partially by direct radiation, fresh air and moisture. But neither the open fire nor the stove, as desirable as they may be in many small rooms, are suitable for large rooms, especially where many persons are assembled. Heating principally by circulating warmed air, or in combination with direct radiation from exposed pipes filled with steam or hot water, is in such cases more convenient. ”

“ The latest evidence submitted at the Royal Institute of British Architects and at the International Congress of Hygiene, Budapest, has conclusively demonstrated that heated air employed for the double purpose of ventilation and warming is not only unhealthy, but fails as an efficient heating medium. ”

“ Stations located in small villages or in the open land will show a greater number of recorded cold waves than those located in large cities, where the heat stored up by pavements and brick buildings during sunshine each day, and where the heat from thousands of chimneys, and maybe millions of human beings, holds the minimum temperature of night much above that of the free air in the open country. ”

“ Most elaborate and ingen{145}ious systems of ventilation have been devised and put into our larger houses, and public buildings like libraries, court-houses, capitols, and schools. Some of them drive the air into each room by means of a powerful steam, or electric, fan in the basement; others suck the used-up air out of the upper part of each room, thus creating an area of low pressure, to fill which the fresh air rushes in through air-tubes or around doors and windows. They have elaborate methods of warming, filtering, and washing the air they distribute. Some work fairly well, some don't ”

“ Manifestly the better and tighter the building the more need there is for special means of ventilation.
In the days when open fireplaces were almost the only means of heating houses they were of great value in aiding ventilation. Nowadays our stoves, radiators and furnaces do not help us in this matter, and we must take additional pains to see that ventilation is provided 383in some other way. Of course the simplest and most perfect method is to permit the free passage of the wind through open doors and windows. Every room should have its air thus completely renewed at least once a day. ”

“ Furthermore, experience shows that in order to ensure reliability it is necessary to have a separate flue for almost every room and to locate the radiators, directly beneath the vertical flue, so that in buildings of any size, especially those more than one or two stories in height, the arrangement of radiators in the basement becomes difficult, and the system of air flues, which are necessarily large, is complex and expensive in space and also in construction. ”

“ It is probable that the ordinary means of ventilation—whether by furnace or fan—may be aided by a change in the force or agency employed for the purposes of haulage and other independent work. As an instance of my meaning, I may mention that the93 apparatus which I have introduced in South Wales, and which, by means of compressed air used as a motive power instead of steam, draws trams and pumps water with complete success, is found to generate ice in an atmosphere which is naturally hot and oppressive. ”

“ For reasons of health it may be assumed that no system of heating is advisable which does not provide for a constant renewal of the air in the locality warmed, and on this account there is a difficulty in treating as separate matters the subjects of heating and ventilation, which in practical schemes should be considered conjointly. ”

“ An important consideration in all cases of hot-air heating is that the air be taken from the outside through a conduit instead of using the air from the cellar, as is too frequently done. In some cities and suburban towns, pure air is brought into the cellar through a conduit where it passes through a box in which it is heated by steam pipes, the steam being brought from a central plant which supplies several hundred houses. The air when heated passes through flues to the several rooms of the dwelling, and is turned on and off by registers in the usual way. ”

“ Priestley and Dalton have long ago shown the co-existence of these two-fold crossing currents of air, even through the substance of stone-ware tubes. True economy of heat, and salubrity, alike require vivid combustion of the fuel, with a somewhat brisk draught inside of the chimney, and a corresponding abstraction of air from the apartment. Wholesome continuous ventilation, under the ordinary circumstances of dwelling houses, cannot be secured in any other way. ”

“ The hot water in the radiators cools and, in cooling, gives up its heat to the rooms and thus warms them.
In hot-water heating systems, fresh air is not brought to the rooms, for the radiators are closed pipes containing hot water. It is largely for this reason that thoughtful people are careful to raise windows at intervals. Some systems of hot-water heating secure ventilation by confining the radiators to the basement, to which cold air from outside is constantly admitted in such a way that it circulates over the radiators and becomes strongly heated. ”