US2004226A - Steam heating system - Google Patents

Description

June 11, 1935.

J. B. STICKLE STEAM HEATiNG SYSTEM Filed July 13, 19 29 3 Sheets-Sheet 1 INVENTOR. Jory/v.8. 577cm:

ATTORNEY;

June 11,- 1935.

J. B. ST ICKLE STEAM HEATING SYSTEM s Sheets-Sheet 2 Filed July 13, 1929 B I335 I33 I/ [Ill/V l/IVI I ill INVENTOR. Jam .3. ,5 77cm E.

' ATTORNEYJ.

June 11, 1935. J s c STEAM HEATING SYSTEM 3 Sheets-Sheet 3 Filed July 13, 1929 INVENTOR. J'amv .5: 577cm E.

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I ATTORNEYJI I Patented June 11, 1935 UNIT-Ensures PAiTENTWOFFICE STEAM HEATING SYSTEM John B. Stickle, India1iapolis,Ind. Application July 13, 1929, Serial No. 378,128

5 Claims. (01. 237-9) steam heating has been'by direct control of the steam pressure or heating pressure"; in the pipe lines supplying steam to the radiating surfaces. This steam pressure is usually maintained above atmospheric pressure. By reducing heating pressure considerably below atmospheric pressure when heating requirements are not severe, o important savings in steam consumption may be made since the temperature of steam decreases rapidly with a decrease in absolute pressure and since the radiation from the heating surface is directly proportional to the temperature differ- 5 ence between the steam therein andthe room to be heated. For example, ifthe heating system of a building is designed, as is usually the case, to heat the building to 70- degrees ,Fahrenheit indoor temperature with five pounds per square inch ,of steam pressure above atmospheric pressure, 228 degrees Fahrenheit steam temperature and zero degrees Fahrenheit outdoor temperature, the-standard radiation computations show that the building will be heated to the same .in-

door temperature with a stream pressure. of twelve inches of vacuum, steam temperature 187 degrees Fahrenheit and an outdoor temperature of 18 degrees Fahrenheit. Therefore, when the outdoor temperature rises from zero degrees to 18 degrees Fahrenheit, the steam pressure may be reduced from five pounds above atmospheric to' twelve inches vacuum below atmospheric and the steam temperature correspondingly reduced from 228 degrees Fahrenheit to 187 degrees Fahrenheit. Under these conditions, a saving of 26% in steam consumption may be made with no decrease in heating comfort. When the outdoor temperature rises higher than 18 degrees Fahren- .heit, increased economies may be made by reducb9 ing the heating pressure to still lower absolute values.

In thesingle pipe heating systems in common use, the steam is supplied to the heating elements and the condensate returned therefrom through'a single pipe. Asingle steam trap is supply source;

used to remove the condensate from the pipe line supplying a plurality of heating elements.

The principal feature of this invention resides in the provision of'a single pipe steam heating system wherein the pressure of the steam in the heating elements may be carried either above or below atmospheric pressure as desired irrespective of .the pressure in the boiler or other steam Another feature of the invention resides in the provision of control means for varying the steam pressure or vacuum in the heating elements auto- Another feature of the "invention resides in the.

control of the heating pressure for different parts of the building in response to the direction and velocity of the wind. a

In the case of buildings exposed to high winds, a given indoor temperature will require greater heating pressure when a high wind is blowing than will be required on 'a still day, -In the case oflarge buildings particularly, a. higher heating pressure will be required on the'windward side of the building than is required on the leeward side. By means of certain features of the invention hereinafter described, the heating pressure for the whole building may be automatically increased when the wind velocity is above a prede termined point. By means of other features, the heating pressure on the windward side aloneof a building may be similarly automatically increased, depending upon the direction of the wind.

Another feature of the invention resides in the provision of a'time element by means of which not cause variation in tive form of connection for the pressure regulat- 1 ing valve used. Fig. 3 is an electrical wiring diagram for a, variation of apparatus which may be paratus of Fig. 4. Fig. 6 is a diagrammatic rep- 55 ing apparatus used when heating of the various parts of a building is to be differentially varied.

In the form of apparatus illustrated in Fig. 1, a steam pipe I0 furnishes steam to a pressure regulating valve II and thence to a pipe line I2 supplying a plurality of heating elements I3. The pipe line I2 is also used to return condensate from the heating elements by gravity and is connected by pipe I I to a suitable steam trap I5. A pipe line I6 carries condensate from the steam trap I5 tc a vacuum pump I'I driven by an electric motor I8. Each of the heating elements I3 is fitted with a thermostatic air valve I 9 of a common commercial type. A pipe line 20 connects each of said air valves with the pipe line I6.

The regulating valve II is of the diaphragm type wherein a stem 2! is operated to open and close the valve in response to the movements of a diaphragm contained in the housing 22. The housing 22 is divided by the diaphragm intotwo chambers, the chamber above the diaphragm being connected to the pipe line I6 by a pipe line 23 and the chamber beneath the diaphragm being connected to the pipe line I2 by a pipe line.

24. A lever 25 is pivotally mounted at 26 upon a portion of the valve body and is pivotally connected to the stem 2I. Counterweights 21 are attached at the outer end of the lever 25. By this means the stem 2| is lifted to close the valve when the pressure in pipe line I2 exceeds the pressure in pipe line I6 by a suificient amount to lift the counterweights 21. If the difierence in pressure between-pipe lines I2 and I6 is not sufficient to lift the weights 2! the valve I I will be opened allowing steam to pass into pipe line I2 thereby raising the pressure therein to a point high enough to close the valve.

By this means a constant pressure diiiierential is maintained between the pipe line I2 and the vacuum line I6. This pressure differential may be varied as desired by varying the weights 21. The maintenance of a given pressure or vacuum in the pipe line I6 by means of the pump I! will automatically maintain a fixed pressure or vacuum in the pipe line I2 independent of the steam supply pressure in pipe III.

in pipe line I2 and since the pressure in the heating elements or heating pressure is equal to the,

pressure or lower vacuum than the pipe lines I6 and 20, the condensate drains freely from the heating elements and there is proper air elimination from the heating elements, even though a vacuum is maintained therein.

Ordinarily, a pressure difference of approximately one pound per square inch or two inches of mercury is suilicient between pipe lines I2 and I6 for good drainage and air elimination. The regulating valve II is, therefore, ordinarily set to maintain this pressure difference and the vacuum pump is operated to give the proper pressure in pipe line I6 to maintain the desired heating pressure in pipe line I2.

By increasing the vacuum in pipe line I6 a vacuum may be produced resentation of the principal parts of the heat- For automatic control of the vacuum pump motor thermostatic elements 28 and 29 and a regulator 82 are provided. The regulator 82 consists of a housing 83 divided into upper and lower chambers by means of a' diaphragm contained therein. The lower chamber is connected to the pipe line I6, and the upper chamber is open to the atmosphere. The diaphragm is connected to a stem 84 adapted to operate a lever 85 of an electric switch box 86. A lever 81 is pivoted to a member 88 supported by the housing 83 and is pivotally connected to the stem 84. A counterweight 89 is carried on one end of the lever 81.

The thermostatic elements 28 and 29 are herein shown respectively inside and outside the building wall 30. These elements are connected by means of wires 3| with the motor controller 32 and the two elements are connected in series. The outdoor element 29 may be adjusted to close its circuit when the outdoor temperature is above 18 degrees Fahrenheit or any other predetermined temperature. The inside thermostat may beadjusted to close its circuit when the indoor temperature is above a second predetermined temperature,usually about '70 degrees Fahrenheit. The switch box 86 is connected by wires 90 to the wires 3| and is, therefore, in parallel with the two thermostatic elements. The motor controller 32 is of a. standard type adapted to run the motor at a predertermined speed so long as both the thermostatic elements are in the closed circuit condition or when the circuit is closed in the switch .box 86. When the circuit in the switch box 86 is opened and one or both of the thermostatic elements is in-the open circuit condition, the motor will be stopped.

As an example of the operation of the system so far described, let it be assumed that the radiation surfaces are designed to heat a building properly to '70 degrees inside with zero degrees Fahrenheit outside temperature with a heating pressiire of five pounds per square inch above atmospheric pressure, corresponding to a steam temperature of 228 degrees Fahrenheit. It has beenfound by calculation and by experience that when outside temperature is 18 degrees Fahrenheit, a. heating system so designed will heat the building with no loss of heating comfort with a heating pressure of twelve inches of vacuum, corresponding to a steam temperature of 187 degrees Fahrenheit. In that case, the weights 89 will be adjusted so that the regulator 82 operates to close the circuit in switch box 86 when a pressure of four pounds above atmospheric is reached in pipe line I6. The starting of the motor causes the withdrawal of condensate and air from the pipes I6 and 20 until the pressure reduces below the said four pounds. The reduction of pressure results in the movement of the regulator 82 to open a circuit in switch box 86 thereby stopping the motor. This intermittent operation of the motor results in the maintenance of a substantially constant pressure of four pounds above-air mospheric in the pipe I6. If the weights 2! are adjusted for a one pound pressure diiference, a

fourteen inches of mercury in thefpipe lines I6 and 20 when operated continuously- This auto-' matically reduces the heating pressure to twelve 'inches of vacuum.

A variation of the control is illustrated in Fig.

2 wherein the pipe line 24 connects pipeline I2 with the lower chamber of the housing 22 as before but the upper chamber of the housing is left open to the atmosphere by an opening I23. A lever I25 pivoted to the stem 2I and to thevalve body at I26 extends in both directions and is adapted to receive weights I 21 at either end. By

' placing the weights as illustrated in Fig. 2 a constant pressure below atmospheric pressure is maintained in pipe I2 independently of the steam supply pressure. By placing the weights I21 on the opposite end of the lever I25 a fixed pressure above atmospheric pressure may be maintained.- In this case, the motor will be run at a constant speed to give as high vacuum as necessary for proper drainage with the highest expected vacuum in pipe line I2. The variations in the heating pressure or vacuum are then obtained en-' tirely by manipulation of the counterweights I21. With the apparatus just described, only one change of pressure is possible. Further increase of 'efficiency is obtained when pressure is changed by several steps. This is possiblewhen the motor I8 is controlled by a' plurality of thermostats as illustrated in Fig. 3. In this figure, thermostats 34, 35, and 36 may be adjusted to close their electrical circuits at successively increasing temperatures, for example at 10 degrees, 30 degrees and degrees respectively. The electric circuits from these thermostats control a plurality of normally" open relays 31 which are arranged .to short circuit resistors 38 in the circuit of the with weather conditions, an arrangement of parts is used, such as shown diagrammatically. in Figures 4, 5 and 6. In Fig. 6, heating elements 2I3 are divided into four groups indicated respec tively by the letters N, E, W and S. These groups may be considered as supplying the heating re-' quirements for the north, east. west and south sides of the building respectively. Each group of heating elements is supplied with steam by a steam pipe Bill which also acts as condensate return pipe in the manner described. Each of the pipes M2 is connected to a steam main 2I0 by 'means of a regulating valve 2 and suitable branch pipes 2 Ilia. Each of the heating elements is fitted with a thermostatic air vent 2I9 and the air vents. of each group of radiators are connected to an air removal pipe 220. The pipes 220 are all connected to a common air and condensate line 286 which is in turn connected to a pump 2I1 driven by a motor 2i8. A steam trap 2I5 is connected by means oi a pipe 2M to each of the pipes 12 92 and serves to remove the condensate from the said pipes. Each of the traps'2 I5 is connected to the pipe "Mt. i

, Each of the regulating valves 2II isof the diaphragm type wherein astem MI is operated to in the corresponding pipe line 2I2.

2 I 6 by pipe lines 223 and the chamber beneath the diaphragm for each valve being connected to the corresponding pipe line 2I2 by a pipe line 224.

A lever 225 is pivotally mounted at 226 upon a portion of each of the valve bodies and is pivotally connected to the correspondingstem 22I. Counterweights 221 are attached to each of the levers 225. By this means, each of the stems-HI is lifted to close its valve when the pressure in the corresponding pipe line 2I2 exceeds the pressure in pipe line 2I6 by a suflicient amount to lift the counterweights 221.

Each of the valves 2 has associated therewith a solenoid carried on a portion 24! of .the housing 222 and numbered respectively 15, 16, 11 and 18 for the east, west, south'and north groups of heating elements respectively. A plunger 242 for each solenoid is supported on a spring 2&3 suspended from the end of the corresponding lever 225. When the solenoids are deenergized, the

springsand plungers hang as dead weights on the solenoid is not energized, this pressure difierence depends only upon the weight of the solenoid plunger, the spring and the counterweight 221. When one of the solenoids is energized, however, a greater pressure difference will be maintained Thus the energizing of one of the solenoids 15, 16, 11 or 18 serves to increase the heating pressure in the portion of the building controlled thereby.

The pressure in the pipeline 2IB is controlled by 'controlling the operation of the motor 2I6.

" This may be done in the manner previously described for the apparatus shown in Figure 1 or by the use 'of a variable speed motor control as shown in Figure-3.

Fig. 4 illustrates a form of electric apparatus responsive to the direction and velocity of wind and used to control the heating pressure for different parts of the building. A vertical shaft Ml is carried on a suitable step bearing =15 and a bearing 46 in the housing 41 and cover 68 respectively of a switch box. Said box may be located at a convenient position, preferably on the roof 49 of the building. A weather vane 50 is carried on the upper end of the shaft 44 and rotates the said-shaft in response to changes in wind direction. Carried on the said shaft within the switch box is an arm 5! of insulation material carryingspring contact members 52 adapted to engage contact members53, 55, 55, 58 and 51. The last-mentioned contact members are carried on an insulation piece 58 supported within the housing 41. The contact member 53 is circular in form and is always in contact with its corresponding member 52. Contacts 55, 55, 56 and 51 are arcuate in form as shown in Fig. 5 and are adapted to contact with their respective members 52 when the wind is from the east, west, north or Si in the housing 62 and the cover 63 respectively of "a second switch box also mounted in a convenient position on the roof of the building. Carried on the upper end of the shaft 59 is a wind gauge wheel 64 of the general type used by the United States Weather Bureau in measuring the velocity of the wind and adapted to rotate at a velocity proportional to said wind velocity. Carried on the shaft 59 within the housing is a usual type of fiy-ball governor indicated generally by the numeral 65. Pivotally mounted within the housing is a bell crank 66 carrying on one arm a contact member suitably'insulated therefrom and adapted to contact with a second contact'member 68 carried upon and suitably insulated from the housing 62. The opposite arm of the bell crank 66 is associated with the movable member 69 of the fly-ball governor 65 to close the contact be-- tween contact members 61 and 68 when the flyball governor has reached a predetermined speed. By adjustment of the actuating spring 10 of the fly-ball governor, this contact may be made to occur at any desired wind velocity.

The electrical wiring for this control apparatus is shown in Fig. 5 wherein a pair of lines H lead from a suitable source 'bf electric potential to the double pole knife switch I2. One pole of said switch is connected by line 13 to the contact member ,68. The contact member 61 is connected by line 14 to the contact member 53. Contact I members 52 are electrically connected to each other. Contact members 54, 55, 56 and 51 are connected respectively to solenoids I5, 16, 11 and 18. A common return line 18a leads-from the Y opposite terminal of each of these solenoids to the contact member 19 of a time relay switch. The opposite contactor 8B of the time relay switch is connected to the second pole of the knife switch 12. A solenoid 8| actuates the time relay switch and is connected by one terminal to the contact member El and by the opposite terminal. to the contact member 80 of the time relay switch. This switch is of a common form wherein contact is made between contact members 19 and =86 only after solenoid M has been continuously actuated for a predetermined length of time.

Bythe operation of'this circuit, the contact 67-68 is made only when the wind velocity has reached a point which will cause a difference in the heating required in diiferent parts of the building. The closing of the said contact'actuates solenoid 8i and, at a, predetermined time thereafter, the l9-80 contact is closed. The latter contact, therefore, is not closed until the predetermined wind velocity has been main tained for a predetermined length of time. Thus a sudden gust of wind will not actuate the ap-v paratus.

' The closing of contacts 61-48 makes a circuit through line H, contact 53, the contact members.

52 to one of the arcuate contacts, depending upon the direction of wind velocity. Each of the arcunorth wind, for example,"blowing. at a predetermined velocity for a predetermined length of time, will actuate solenoid I1 to raise the heating pressure on the north side of thebuilding. Similarly, a west wind will raise the heating pressure onthe west side of the building. By the overlapping of the arcuate contacts as shown in Fig. 5, a northwest wind will actuate both solenoids I6 and ill to raise the heating pressure on both the north and west sides of the building.

In the case of small buildings or wherever it is desired to increase the heating pressure in the whole building when a high wind is blowing, regardless of the'wind direction, the wind direction controller may be omitted and all of the solenoids may be operated directly from the wind velocity controller. .In this case only one regulating valve Ii would be required for the entire building but as many could be used as convenient. The wind control apparatus herein shown may also be used independently of the particular form of apparatus, herein described. For example, a common form of pressure-reducing valve or valves-may be used and controlled independently of the return line vacuum to increase the heating pressure as desired for variation in wind velocity and direction.' 1

It is to be appreciated that several variant forms of the standard apparatus such as steam traps i5, thermostatic valves I9, heating elements I3, etc. may be used without departing from the invention. As an example, a common form of U-bend water seal may be used in place of the steam .trap. In the following claims the term steam trap is intended to include such equivalent structures. In the claims the word pressure indicates pressures both above and below atmospheric pressure.

The invention'claimed is:

1. A steam heating system including a steam supply main, a radiator, a secondary pipe line for supplying steam from said main to said radiator, a regulating valve interposed between said secondary pipe line and said steam supply main, a steam trap receiving condensate from said radiator, a vacuum pump, a condensate removal .pipe line connecting said steam trap and said quirements are relatively severe, and other means operating in response to decrease in heating requirements for controlling said pump to maintain a lower condensate removal pressure.

2. A steam heating system including asteam supply main, a radiator, a secondary steam pipe supplying steam from said main to said radiator, a regulating valve interposed between saidsteam supply main and said secondary steam pipe, an

air removal valve for removal of air from said radiator, a pump, an air removal pipe connecting said air removal valve and said pump, connections between said secondary steam pipe, said air removal pipe and said regulating valve for operating said valve to maintain a substantially constant pressure-difierence between said pipes,

a regulator associated with said air removal pipe to control the operation of said pump to maintain a substantially constant air removal pressure when heating requirements are relatively severe, T

and other means operating in response to a decrease in heating requirements for controlling said pump to maintain a lower air removal pressure and thereby to maintain a correspondingly lower pressure in said. steam pipe.

3. A steam heating system including a steam supply pipe, a radiator, secondary pipe line supplying steam from said steam main to said radiator, a pump, an air removal pipe line connecting said pump and radiator for removal of air therefrom, thermostatic apparatus located in a region whose temperature is indicative of the heating requirements of the system, means controlled by said thermostatic apparatus and operating said pump to increase the speed thereof and reduce the pressure in "said air removal 'line in response to an increase in temperature at said thermostatic apparatus and to decrease the speed of the pump and thereby increase the pressure in said air removal pipe in response to a decrease in temperature at said thermostatic apparatus, a regulating valve interposed between said supply main and said secondary pipe line, and a differential controller connected to said secondary pipe line and to said air removal pipe line and operating said valve to throttle steam flow to said secondary pipe line in response to a decrease in pressure in said air removal pipe and to increase said steam flow in response to an increase in pressure in said air removal pipe, said controller being biased to maintain a sufiicient pressure difference between said secondary pipe line and said air removal pipe line for adequate air removal.

4. A steam heating system including a steam supply main, a radiator, a secondary pipe line supplying steam from said steam main to said radiator, a condensate pipe receiving condensate drained from said radiator, a condensate removal pump connected to said condensate pipe,

thermostatic apparatus located in a region whose temperature is indicative of the heating requirements of the system, means controlled by said thermostatic apparatus and operating said pump to increase the speed thereof and reduce the pressure in said condensate removal line in response to an increase in temperature at said thermostatic apparatus and to decrease the speed of the pump and thereby increase the pressure in said condensate removal pipe, in response to a decrease in temperature at said thermostatic'apparatus, a regulating valve interposed between said supply main and said secondary pipe line, and a differential controller connected to said secondary pipe line and to said condensate pipe line and operating said valve to throttle steam 5 flow from said supply main to said secondary pipe line inresponse to a decrease in pressure in said condensate line and to increase said steam flow in response to an increase in pressure in said condensate line, said controller being biased to give a pressure difference between said sec- (ndary pipe line and said condensate removal pipe line sufliicient for adequate condensate removal. I 5. A single pipe steam heating apparatus ineluding a steam supply main, a plurality of pressure regulating valves, pipe lines supplying steam from said supply main to said regulating valves, a plurality of groups of radiators, a plurality of branch pipe lines each supplying steam from one of said regulating valves to one of said groups of radiators and each returning condensate from its associated radiators, a plurality-of steam traps each receiving condensate from one of said branch pipe lines, an air removal pipe line removing airfrom said radiators, a pump operating to remove air from said air removal pipe line and condensate from said steam traps, a plurality of regulators each operating one of said regulating valves to maintain a substantially constant pressure difference between said air removal pipe line and its associated branch pipe line, and each of said regulators being adjustable to give a predetermined pressure difference to each J group of heating elements independent of the others, a device responsive to wind direction and velocity for controlling said adjustment, and a timing element by means of which said adjustment control device is operable only when a predetermined wind velocity has been maintained 40. for a predetermined length of time.

JOHN B. STICKLE.

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