US1024547A

US1024547A - Boyers

Info

Publication number: US1024547A
Authority: US
Publication date: 1912-04-30
Anticipated expiration: 1929-04-30

Description

C. A. BALL. STEAM HEATING SYSTEM. APPLICATION FILED NOV.-6, 1902.

Patented Apr. 30, 1912.

3 SHEETBSHEBT 1.

Patented Apr. 30, 1912.

3 SHEETSSHEBT 2.

C. A. BALL.

STEAM HEATING SYSTEM.

APPLICATION FILED NOV. 6, 1902.

Patented Apr. 30, 1912.

3 SHEETS-SHEET 3.

avweufoz Q Mim iii Witnesses UNITED STATES PATENT OFFICE.

CHARLES A. BALL, OF PHILADELPHIA, PENNSYLVANIA, ASSIG-NOR T0 WARREN WEBSTER 82; COMPANY, A CORPORATION OF NEW JERSEY.

STEAM-HEATING SYSTEM.

To all whom 'it may concern:

Be it known that I, CHARLES A. BALL, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia, State of Pennsylvania, have invented new and useful Improvements in Steam-Heating Systems, of which the following is a specification.

My invention relates to steam heating sys tems adapted to employ either live or exhaust steam as the heating medium, and has for its object to provide an improved means for removing the air and for returning the water of condensation from both the supply and return sides of the system to the boiler.

The invention is designed particularly for use in systems wherein the source of steam supply is remote from the radiators or coils to be heated, even at a distance of a mile or more, and is particularly adapted for use in heating a plurality of separate buildings lo cated at varying distances from the common source of steam supply.

In the accompanying drawings: Figure 1 is a side elevation, partly in section, illustrating my improved construction. Fig. 2 is a top plan "iew, also partly in section. of the same. Fig. 3 is a diagram illustrat ing the application of my invention to a series of independent sets of radiators in the same or separate buildings.

Similar numerals of reference denote corresponding parts in the several views.

In the said drawings the reference numeral 1 denotes the steam supply main for the system, the same being adapted to be connected to a boiler direct for receiving a supply of live steam, or to the exhaust side of power fixtures to receive a supply of exhaust steam, it being also understood that these connections may be such that live and exhaust steam may be employed alternately in the same system, according to the conditions prevailing. Tapped into the main 1, and extending downwardly therefrom, is a drip pipe 2 adapted to receive any water of condensation from said main.

The main 1 extends at the right to the heating radiators or coils of the system, the return from which is through pipe 3, which divides at 4 into a water return pipe 5 and a vacuum pipe (3, the latter being connected at the left with the usual vacuum pump now commonly employed in systems using exhaust steam for removing the air and water Specification of Letters Patent.

Application filed November 6, 1902.

Patented Apr. 30, 1912. Serial No. 130,831.

of condensation from the return side thereof. Located in said exhaust pipe 6 is a downwardly opening reducing valve 7, the same having a downward pressure exerted thereon by weight 8, and having its stem 9 connected to a diaphragm 10 in chamber 11, the underside of the latter being exposed to atmospheric pressure through apertures 12 and having its upper side in free communication with the exhaust pipe 6 on the radiator side of valve 7 through pipe 13, said reducing valve thus dividing the pipe 6 into two chambers, one containing a. vacuum of the degree maintained by the vacuum pump, and the other a vacuum regulated to suit the requirements of the radiators or coils at this point.

Located below the main 1 are two

chambers

14 and 15, divided by a partition 16, in which is located a connecting pipe 17 having a valve 18 therein for permitting a passage from chamber 14 to chamber 15, but for preventing a passage in the reverse di rection. The pipe 5 extends into an enlargement 19 containing a. rel'novable strainer or sieve 20 for catching any impurities in the condensation water, and said enlargement is tapped into chamber 14, as shown. A pipe 21 extending from the lower portion of chamber 15 is provided with an upwardly opening valve 22, and a cut-off valve and communicates with a force pump of any conventional type located in the boiler room for returning the 'ater to the boiler.

Located in chamber 14 is a rod 21 mounted, but vertically mo able, in suitable guides 25, and carrying a float 2G vertically movable thereon. series of three adjustable stops 27 is also mounted on said rod 21, as shown, and lying between the upper two of these stops is the bifurcated end of an arm 28 eml'n'acing rod 24 and forming part of a bell-crank lever 29 extending through a bushing 30 to the exterior of chamber 14, and having its other arm 31 connected, by means of a rod 32, with the operating arm of a valve 34 located in a pipe 33 extending from the pipe 6, on the vacuum pump side of valve 7 therein, to chamber 15, as shown.

Located in chamber 15 is a vertical rod 36 also mounted and vertically movable in guides 37, similar to guides 25, said rod also carrying a vertically movable float 38, and having a series of three adjustable stops 39 thereon, between the two lower ones of which extends the bifurcated end of an arm 40 embracing rod 36 and forming part of a bell-crank lever 41 extending through a bushing 42 to the exterior of chamber 15, and having its other arm 43 connected, by means of a rod 44, with the operating arm 45 of a valve 46 located in a pipe 47 tapped into chamber 15 and connected with a pipe 48 running to the lower end of drip pipe 2. Between the drip pipe 2 and chamber 15 the pipe 48 is provided with a check valve 49 opening toward chamber 15 only, while said pipe 48 is extended beyond pipe 47 and opens to the atmosphere, a check valve 50 opening inwardly only, permitting ingress of air under conditions hereinafter described.

Extending from vacuum pipe 6, on the radiator side of Valve 7 therein, is a pipe 51 communicating freely with chamber 14, for a purpose hereinafter to be described; while extending from the side of drip pipe 2 also to said chamber 14 is a pipe 52, a suitable relief fitting 58 for the air and water of condensation from drip pipe 2 being interposed between pipe 52 and drip pipe 2, said relief fitting being preferably of the construction disclosed in Letters Patent No. 702,386, granted to me June 10, 1902.

In order that the system may be adapted to receive alternately live or exhaust steam, I also prefer to employ as the relief for the radiators or coils thereof fittings of the type shown in my above mentioned patent, each radiator or coil being provided on its return side with one of said fittings, the same being in turn connected to its branch of the common return pipe 3 of the system.

As shown in Fig. 1 of the drawings, the steam supply main 1, the vacuum and

water return pipes

6 and 21, and the return pipe 3 are all inclined upwardly from the point where the

chambers

14 and 15 are located, thereby indicating that said chambers are located at the lowermost point in the system, not only below all the radiators, but also below the steam supply and the vacuum and force pumps, such relative locations being essential to the effective operation of the system, as hereinafter described. It will also be carefully noted that there is a vacuum pump connected with pipe 6 and aforce pump connected with pipe 21, these two pumps being entirely separate and distinct.

From the above description the operation of my improved construction will be understood to be as follows: The system being put in operation and steam being admitted to main 1 will flow therethrough to the radiators, all water of condensation in said main gravitating naturally to drip pipe 2, which, as seen, is located at the lowest point in said main, said water building up in said drip pipe until relieved in one of two ways, as hereinafter described. The vacuum and force pumps, connected with

pipes

6 and 21, respectively, are started simultaneously with the admission of steam to main 1. It will be seen, however, that at this time the valve 7 in pipe 6 is wide open, due to the fact that the pressures on both sides of diaphragm 10 are equal, while the weight 8, being the only operating medium on valve 7, has forced it downwardly and thus open. Assuming that the system will operate perfectly under a vacuum of 10 inches, the vacuum pump is preferably run constantly at a speed to create a much greater vacuum, say, 20 inches, which, by regulating weight 8, can be reduced through valve 7 to remain constant at 10 inches on the radiator side of said valve, it being readily understood that as soon as the vacuum begins to be felt in pipe 6 it will communicate with the upper side of diaphragm 10 through pipe 13, and thus tend to close valve 7, the pressure on the underside of said diaphragm remaining constant at atmospheric pressure. This con stant- Vacuum of 10 inches will thus be communicated to all the radiators or coils of the system through pipe 3 and the usual branch pipes, and will thus rapidly remove the air therefrom to permit the circulation of exhaust steam through main 1, or, when live steam is employed, will aid in its rapid movement to the radiators. Now, by means of pipe 51, the vacuum in pipe 6 is also constantly exerted in chamber 14, the result being that as the pressure or vacuum in pipes and 6 is equal, the combined water of condensation and air returning down pipe 3 will separate at 4, the water flowing by gravity through enlargement 1t) into chamber 14, while the air will pass along pipe 6 to the vacuum pump, where it will be dis charged to the atmosphere. It will thus be seen that the vacuum pump performs no function Whatever in returning the water of condensation, the flow of the latter to chamber 14 being entirely by gravity. The water flowing into chamber 14 builds up therein, but is prevented from flowing therefrom into chamber 15 because the constant vacuum of 10 inches maintained in chamber 14 will be greater than the suction created in chamber 15 by the action of the constantly running force pump connected with pipe 21. When, however, the water has built up in chamber 14 sufficient to raise float 26, the latter, contacting with intermediate stop 27, will raise rod 24 and with it arm 28 of bell-crank lever 29, thus opening valve 34, through parts 31. 32 and 33, and thus exerting the full vacuum of 20 inches, constantly existing in pipe 6 to the left of valve 7, upon chamber 15. This difference between 20 inches vacuum in

chamber

15 and 10 inches vacuum in chamber 14 will cause an instant discharge of the water in chamber 14 through valve 18 into chamber 15, which will continue until float 26, by contacting with the lowermost of the stops 27 on rod 24, forces said rod downward, and, through uppermost stop 27, returns arm 28 to its initial position, thus closing valve 34 and shutting off the vacuum from chamber 15. Now, although the force pump connected with pipe 21 is running constantly, so long as chamber 15 is closed to atmospheric or other pressure, the only result will be a limited building up of a leg of water in pipe 21, which is prevented from possible back flow by valve 22. But when water has discharged into chamber 15 sufiiciently to raise the float 33 to the position shown in Fig. 1, the same, by contacting with uppermost stop 39 on rod 36, will have raised said rod, as shown, which will, through lowermost stop 39, raise arm 40 of bell-crank lever 41, and thus, through parts 43, 44 and 45, open valve 46, and thus establish communication between pipe 43 and chamber 15. Now, if live steam is being employed in main 1, the pressure thereof on valve 49 will raise the latter, and an immediate discharge of the water of condensation in drip pipe 2 will take place through

pipes

48 and 47 into chamber 15, the same being followed by the live steam, which will afford the necessary pressure in chamber 15 to permit the force pump connected to pipe 21 to remove the water in said chamber and return it to the boiler or feed water heater. said action continuing until float 33 falls in contact with intermediate stop 39 and forces down rod 36 and arm 40, thus again closing valve 46. The steam contained in chamber 15 will now condense and will thus assist in creating a vacuum therein, thus rendering the next intermittent action of chamber 15 more rapid when valve 34 is again opened. \Vhen, however, exhaust steam is being employed in main 1, the necessary pressure in chamber 15, when valve 46 is opened, will be supplied by atmospheric air entering pipe 43 through valve 50, thus rendering the chamber 17 operative under either condition of steam supply to main 1. It will be under stood that should the water of condensation in drip pipe 2 build up therein against valve 49, when it reaches the level of valve 52 it will automatically discharge through pipe 52 into chamber 14, the constant vacuum of 10 inches therein causing said valve to function as will those on the radiators of the system.

In Fig. 3, I have shown my invention when extending over great areas applied to independent sets of radiators or coils in the same or in separate buildings. In Fig. 3, A, B and C represent different buildings, or A and B may be considered as different parts of the same building. K are the radiators, J are the steam supply pipes and 3 are the return pipes. The radiators are provided as usual with automatic valves at their connection with the returns to prevent free passage of steam, while allowing the air and water to pass through the re turns. D is the boiler or other source of steam supply such as the exhaust of an engine; E is the vacuum pump; F is the force or boiler feed pump; H is the vacuum return pipe for air, and G is the pipe for returning the water of condensation. Where A and B are in the same building, the source of steam supply may be equally distant from both and their heating equipments. In Fig. 3, the extent of vacuum in the several buildings or parts of the buildings may be the same or diti'erent according to predetermined adjustment but in all cases the steam is caused to circulate under a degree of vacuum in the return pipe which is less than the initial degree of vacuum in the pipe H created by the vacuum pump E or other device.

This system is intended more particularly to be employed where the building or build ings to be heated are located at a distance from the source of steam supply, even as much as a mile or more apart, for it will be apparent that by maintaining a constant and excessive vacuum in pipe 6 on the boiler side of valve 7 and by regulating said valve to reduce to suit the conditions of the building to be heated, a vacuum may be maintained on the radiator side that will obtain a maximum of elficiency, and will op erate not only to assist the circulation of live steam in main 1 and through the radiators, but also to draw exhaust steam therethrough, a result not heretofore accom plished in this manner. It will also be understood that a plurality of separate buildings more or less remote from each other and from the boilers, power fixtures and vacuum and suction pumps may be heated simultaneously by providing one of my improved apparatus for each building, there being a common steam supply main, vacuum return pipe and water return pipe connected to all of said apparatus, each apparatus being constructed and having its valve 7 regulated to suit the conditions of its building. In usin therefore, in the claims appended hereto the terms in proximity to and remote from I wish to be understood to refer to a system wherein the source of steam supply is located at a considerable distance from the radiators or coils, in contradistinction to a system wherein the source of steam supply is located in the basement of the building containing the coils or radiators, which in the present use of the term would constitute a source of steam supply in proximity to the radiators or coils.

By having the pipe 6 porcelain or tin lined from the boiler room to the valves 7 I reduce the friction therein to a minimum, and, in the case of each building to be treated, practically bring the vacuum pump to its valve 7 and provide accurate means for regulating the vacuum to the conditions required at any point, Whether more or less remote.

It will be observed that the water of condensation first passing down pipe 5 into chamber 14 is retained for a time in the latter. thus losing some of its heat units therein by radiation, and said water is again retained for a time in chamber 15, thus losing more of its heat units therein. Finally, the intermittent action of the force pump on the water in chamber 15 causes the water to build up in a leg in the pipe 21 on its way back to the boiler and to have periods of quiescence in said pipe 21 while the chamber 15 is filling up, thus causing a further loss of heat units to the water, the result being that the 'ater will reach the source of steam supply in a comparatively cool condition, thus rendering unnecessary the employment of a jet condenser with the same, such as is usually found necessary to en'iploy, especially where a vacuum pump is employed. If found to be too cool, the water before being returned to the boiler may be passed through the usual feed water heater.

The merit of the present invention lies in the fact that two or more independent groups of radiators, coils or heating apparatus of any form, whether under one roof or two or more roofs, whether relatively close together or far apart, may be employed to supply heat under different conditions or requirements and yet receive the initial energy, both thermal and kinetic, from one general source, thereby providing capacity for extended heating operations at a minimum cost. It frequently happens in large factories including a series of buildings that the several buildings require different conditions of heating and that some will have greater ditiiculty of circulation than others, and hence by my improved system the extent of vacuum in the return pipe which provides a dilterence in pressures between the supply and return sides may in each case be made to suit the requirements by merely adjusting the automatic valves 7 to dictate the degree of eon stant vacuum to be maintained in the respective returns. \Vhere this system is employed in large buildings, independent sets of radiators or coils may be supplied by independent sets of steam supply and return pipes, but all receiving their thermal and kinetic energy from a common source, and each set independently controlled by apparatus herebefore described to maintain predetermined degrees of vacuum in the respective returns to cause the steam to enter the radiators by reason of the ditt'erence in pressure between the supply and return pipes of each heating unit or of the supply and return pipes of each set of radiators or heating coils. By this means proper heating of enormous buildings may be accomplished with accurate and perfect regulation consistent with the requirements.

In this application, no claim is made to the method, as that is reserved for another pending application, Ser. No. 130,330 of November 6, 1902.

iVhile I have illustrated my invention, by way of example, with apparatus which I deem an excellent form of my invention for commercial use on an extensive scale, I do not restrict myself to the details, as these may be modified, Within the scope of the claims, Without departing from the spirit of the invention.

Having thus described my invention, what I claim new and desire to secure by Letters Patent is:

1. In a steam heating system, the combination of a plurality of ii'idependent heating units each consisting of a number of radiators, a steam supply main having branches for delivering steam to the respective heating units, a vacuum main extending from a source of Vacuum in excess of the requirements of part at least of the several heating units, a separate vacuum return pipe leading from each of the heating units and connecting with the vacuum main, independent automatic means for each of the heating units operating under the control of the vacuum in the respective return pipes for maintaining substantially constantpartial vacuums in said return pipes in accordance with the requirements of the respective heating units, and independent means for each of the heating units for removing the water of condensation from the return pipe thereof, said means consisting of a steam trap located at the lowest portion of the heating unit and having a float actuated valve controlling communication with the vacuum main.

2. In a steam heating system, a source of steam supply, a plurality of groups of radiators or coils located at different distances from said source of steam supply, a common supply main from said steam supply source to said groups of radiators or coils, a separate return pipe leading from each group of radiators or coils, a separate vacuum maintaining means connected to the return pipe of each group of radiators or coils at. a point adjacent to its said group of radiators or coils to remove the air and water therefrom and comprising in combination a high vacuum chamber, and a 10W vacuum chamber communicating with the return pipe for the group of radiators or coils, means for creating and maintaining a vacuum equal to or in excess of the requirements of the system and maintaining a low vacuum in the low vacuum chamber, and means for separately governing the communication between said chambers according to the requirements for transferring the water of condensation from the low vacuum chamber to the high vacuum chamber.

8. In a heating system, a source of steam supply, a plurality of independent groups or units of radiators or coils, a common supply main from said source of steam supply and having branch supply pipes for supplying steam respectively to the plurality of independent groups or units of radiators or coils, a common main in which is maintained a high vacuum in excess of the requirements of the heating units, return pipes separate from the branch supply pipes each leading from a different one of the plurality of independent groups or units of radiators or coils for receiving the water of condensation and air therefrom, intermittently operating steam traps respectively adjacent to the lower end of each one of the return pipes for receiving the water of condensation therefrom and intermittently discharging it from the heating system said steam traps having means under the control of the water therein for controlling a suction between the said steam traps and the common high vacuum main for causing the water of condensation to be intermittently removed from the traps, separate pipe connections respectively between the common high vacuum main and each of the plurality of independent groups or units of radiators or coils and communicating therewith through the respective return pipes above the level where the water of condensation collects in the steam traps, and an automatic controller in each of said pipe connections for separately and independently controlling the extent of the vacuum Within the respective return pipes and maintaining said vacuums substantially constant and at a relatively lower vacuum than in the high common vacuum main whereby each of the units may be operated under different degrees of vacuum while being dependent upon a common source of steam supply and of high vacuum.

4. In a steam heating system, the heaters, a steam supply pipe for delivering steam to the heaters, and a return pipe for the air and water from the heaters and in which a partial vacuum is maintained, in combination with a high vacuum main in which a vacuum in excess of the requirements of the return pipe is maintained, a pipe connection between the high vacuum main and the return pipe, an automatic controller in said pipe connection for controlling the extent of the vacuum within the return pipe and maintaining said vacuum substantially constant at a relatively lower vacuum than in .water of condensation the high vacuum main, a steam trap connected with the lower part of the return pipe for receiving the water of condensation therefrom and having a communication with the high vacuum main and also provided with means controlled by the level of the water in the trap to intermittently open and close the communication with the high vacuum main whereby the water of conden sation is intermittently withdrawn from the trap under the influence of the high vacuum.

5. In a steam heating system, a source of steam supply, a steam supply main, radi ators or coils connecting with the steam supply main, a water of condensation receiving device, a return pipe separate from the steam supply main extending from the radiators or coils and connecting with the receiving device, means for maintaining a partial vacuum in the return pipe, a steam pipe leading from the steam supply main to the water of condensation receiving device, means intermittently operated by the rise and lowering of the water level in said water of condensa tion receiving device to establish communication alternately between said device and the steam pipe and the means for maintaining the partial vacuum, means for closing communication between the return pipe and the steam pipe when said steam pipe is discharging into the Vater of condensation receiving device, and means for drawing the water from the water of condensation re ceiving device.

6. In a steam heating system, radiators or coils, combined with a steam supply main adapted to convey either live or exhaust steam, a return pipe, a vacuum main connected to the return pipe and having a differential of vacuum in its length, a chamber to receive the water of condensation from the return pipe and adapted to be intermittently connected with the vacuum main at its place of higher vacuum to draw the water into the chamber, a pipe communicating between the steam supply main and said chamber and also between the atmosphere and said chamber, a valve normally closing said pipe to said chamber, check valves respectively permitting flow from the steam supply main and from the atmosphere to said chamber but preventing back flow, means for maintaining suction on said chamber to convey the water therefrom, means operated by the rise of the water level in said chamber for opening the valve in the pipe communicating with the supply main and the atmosphere, whereby under a condition of live steam supply to the system said steam will be intermittently admitted to said chamber to provide the pressure therein to permit the withdrawal of the water therefrom and While under a condition of exhaust steam supply to the system atmospheric air will be admitted to the chamber to provide the pressure required therein, and means to prevent the steam or air admitted to the chamber passing into the return pipe.

7. In a steam heating system, a chamber located in the return side thereof to which the water of condensation runs by gravity, a second chamber communicating with said first chamber, a check valve for preventing back fiow between the said chambers, a pipe in which a partial vacuum is maintained, means operated by the variations in the water level in said first chamber for estab lishing intermittent communication between said second chamber and the pipe in which partial vacuum is maintained to cause the water to flow from said first chamber to said second chamber, means operated by the rise of the water level in said second chamber for admitting pressure therein, and a constantly operated suction pump sucking on said second chamber for intermittently drawing the water therefrom.

8. In a steam heating system, a return pipe, a. vacuum pipe connected therewith, means for producing a constant initial vacuum in said vacuum pipe in excess of the requirements of the system, a vacuum reducing valve for controllably rediucing said vacuum in the return pipe by regulating the con'imunication between it and the vacuum pipe, a closed chamber connected with the return pipe on the radiator side of the reducing valve to which the water of condensation flows by gravity, a second closed chamber in communication with the first chamber, a check valve in said communication for permitting the fiow of water from the first to the second chamber but for preventing back fiow, means operated by the rise of the water level in the first cham her to establish communication between the second chamber and the vacuum pipe on the vacuum creating side of the reducing valve whereby a differential in pressure will be exerted in said chambers to cause the water to flow from the first chamber into the second chamber, means operated by the rise of the water level in the second chamber for admitting steam pressure from the supply main to said chamber, a pump for withdrawing the water therefrom, and a source of steam supply.

9. In a steam heating system, a chamber located in the return side thereof to which the water of condensation flows by gravity. a second chamber communicating with said first chamber, a check valve for preventing back fiow between said chambers, a fioat in said first chamber operated by the rise and fall of the water level therein, a source of vacuum, means operated by the rise of said float for establishing communication between said second chamber and the source of I vacuum to cause the water to flow from said first to said second chamber, a float in said second chamber operated by the rise and fall of the water level therein, means operated by the rise of said float for admitting pressure therein, and means for maintaining a constantly operated suction in said second chamber for intermittently withdrawing the water therefrom under such pressure condition.

10. In a steam heating system, a steam supply main, a return pipe for the water of condensation and entrained air, a vacuum pipe connected with said return having means for producing a differential of vacuum in its length and adapted to withdraw the air from said return, a chamber located below said vacuum pipe and connected to the return for receiving the water therefrom by gravity, said chamber being in constant communication with the lesser vacuum in the vacuum pipe, a second chamber communicating with said first chamber for receiving the water therefrom, means for preventing back fiow of said water between said chambers, means operated by the rise of the water level in said first chamber for establishing communication between said second chamber and the vacuum pipe containing the greater vacuum, means operated by the rise of the water level in said second chamber for establishing communication with the steam supply main, and a constantly operated pump communicating with said second chamber for removing the water therefrom under such pressure condition.

11. In a steam heating system, radiators or coils, combined with a steam supply main adapted to convey either live or exhaust steam, a return, a vacuum main connected to the return and having a differential of vacuum in its length, a chamber connected to the return and adapted to be intermittently connected with the vacuum main at a place containing a higher vacuum than exists in the return to draw the water into the chamber from the return, a pipe communicating between the steam supply main and said chamber and also between the atmosphere and said chamber, a valve normally closing said pipe to said chamber, check valves respectively permitting flow from the steam supply main and from the atmosphere to said chamber but preventing back flow, means for constantly maintaining a suction in said chamber to convey the water therefrom, means operated by the rise of the water level in said chamber for opening the valve in the pipe for communicating with the supply main and the atmosphere, whereby under a condition of live steam supply to the system said steam will be intermittently admitted to said chamber to provide the pressure therein to permit the withdrawal of the water therefrom, while under a condition of exhaust steam supply to the system atmospheric air Will be admitted to the chamber to provide the pressure required therein, and means to prevent the steam or air admitted to the chamber passing into the return pipe.

12. In a steam heating system, a steam supply main adapted to convey either live or exhaust steam, a vacuum pipe connected to the return and having means for producing a differential of vacuum in its length, a chamber in the return adapted to be intermittently connected with the greater vacuum in the vacuum pipe to draw the water there into, a drip pipe located at the lowest point in the supply main to receive the water of condensation therefrom, a pipe communicating between said drip pipe and said chamber and also between the atmosphere and said chamber, a valve normally closing said pipe to said chamber, check valves permitting fioW from the supply main and the atmosphere to said chamber but preventing back flow, a constantly operated means communicating With said chamber to convey the Water therefrom, means operated by the rise of the Water level in said chamber for opening the valve in the pipe communicating with the drip pipe and the atmosphere, whereby under a condition of live steam supply to the system the Water of condensation in said drip pipe and the live steam will be admitted to said chamber to provide pressure therein requisite for the Withdrawal of the Water therefrom by the suction, While under a condition of exhaust steam supply to the system atmospheric air Will be admitted to supply said pressure, and means to prevent the steam or air admitted to the chamber passing into the return pipe.

In testimony whereof, I have hereunto set my hand in the presence of tWo subscribing witnesses.

CHARLES A. BALL.

\Vitnesses HARRY T. STODDART,

L. C. OTTO.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of IPatents, Washington, D. C.