WO1987005378A1

WO1987005378A1 - Central heating system composed of a plurality of water systems located in every living spaces of a building respectively

Info

Publication number: WO1987005378A1
Application number: PCT/KR1986/000007
Authority: WO
Inventors: Jung Woon Lim
Original assignee: Jung Woon Lim
Priority date: 1986-03-10
Filing date: 1986-03-10
Publication date: 1987-09-11

Abstract

A central heating system composed of a central steam source and a plurality of water systems located in every living spaces of a building or buildings respectively. The system has many water systems established in every living spaces respectively, each of which comprises at least one steam-to-water heat exchanger having a heat exchanger interior condition control means, at least one water circulating pump having at least one room temperature control means. A packaged unit is provided in accordance with the system for easy construction of the system comprising said steam-to-water heat exchanger and said water circulating pump.

Description

TITLE OF INVENTION

Central heating system composed of a plurality of water systems located in every living spaces of a building respectively.

TECHNICAL FIELD

This invention relates generally to ^~. central heating system, particulary to a central heating system composed of a plurality of water systems located in every living spaces respectively, and having respective heat exchangers which is a steam-to-water heat exchanger for heating the water of the water system by steam supplied from a central heat source.

BACKGROUND ART

In the art, many systems are known for heating build- ings in a manner of central heating. One of the most typical heating systems is the water heating system. In the water heating system, hot water is a medium for supply¬ ing heat from the heat source, for example .boilers or heat exchangers positioned in a central equipment room, to radiators or heat pannels positioned in every living spaces. Accordingly it is posible to not only vary the flow to the radiators or heat pannels but also vary the temperature of the medium itself. Therefore, during mild weather condition the water temperature is reduced to increase the control function preventing the normal tempe¬ rature overshooting in the area in which the temperature is controlling. While hot water installations have many advantages for single level dwellings and even dwellings with a relatively low head pressure having relatively small floor areas, they pose many problems when used in high level buildings as an extreme head pressure is placed on the base floor piping lines or equipments and/or the central boiler, and when used also in large scale buildings having large floor areas and havinga plurality of living spaces as it is very difficult to provide a balanced heating condition on each floor areas or on each living spaces in the buildings.

In practice, the use of hot water as medium of heat transfer is convenient for providing comportable heating condition on the living space. As a result, recent days most buildings employ the water heating systems, especially the central water heating system for heating their living spaces. However, the water heating system has been filled in the system pipings and system equipments with water as medium of heat, thus the water heating system pose the drawbacks that when used in high and large scale buildings, an extreme head pressure is placed on the Base floor pipings, ittings, equipments and/or boiler,and an extreme heating unbalance is also posed between the heating spaces or zones.

In the prior art, the solution of the heating unbalance of the central water heating system is that the water system comprise the two-pipe reverce return pipings, the thermo- control valves on every radiator branches. However when the solution is adapted to a large scale building or to a high level building, the water system has a need to employ a control system utilizing fine control equipments for balancing the heating conditions because the hot water flow control is more complex and very difficult as much as the number of branches of the water system pipings is increased and the height of the building is increased. By providing such control system in the water system, the system requres a continious water circulating. However, to provide such a control system in a building causes the increasement of building cost and a lot of water circulating energe loss, further more, the water systems have typically the pump stations or mechanical equipment room on the base floor for the circulating pumps though, in case of vertical zoning, the station is on a floor of the Building, thus the friction loss for circulating the heating water through the water loops is very big and the friction loss is increased as much as the Building Height and/or scale is increased. Accordingly, the water system requires a lot of water circulating power.

The more detailed descriptions for the water systems are seen from the ASHREA HAND BOOK system volume section 1, chapter 16 (low Temperature) and chapter 17 (Medium and High temperature) .

In case of very high buildings, some buildings employ the combined steam and water system with vertical zoning for heating the Building without excessive head pressure on the lower floors. Though in this practice, the excessive head pressure is avoided, the problem of the heating unbalance is not solved since the combined steam and water system is employing the water system as it is.

The combined steam and water system is described in the ASHREA HAND BOOK system volume section 1, chapter 13, in this chapter 13 the vertical zoning of the combined steam and water system also is described.

Typically, the water systems require much power to circulate the heating water for transmitting Heat to individual Heating spaces because of the long length of the water travelling. Thus the operating cost of water system is very high over the steam heating system, the water heating system is typically combined with ther o- control system using thermostatic control valves, which adjust the water flow rate introducing to the radiators comprising convectors, unit-heaters, coil-pipes or Heating pannels, which are typically placed in the heating spaces. Therefor, tne therrc-control system which requires a continiQus pump operating causes the operating cost rising. In fact the thermc—control system utilizing the ther o- static valves is available during the pump operation time. This is a considerable drawback when used in a intervally operating water heating system.

Accordingly, what is needed in this time is a novel central heating system in which the heating condition is very comportable and the Heat consumptions of each living spaces are can be controlled freely and simplly by the occupants of each living spaces without increasing the system establishing cost of the building over the prior art systems, and with reducing the operating cost.

Thus, it is an primery object of the present invention to provide a novel central heating system having the high heat efficiency, a reduced volume needed to the system establishment, and a capability to reduce the total build¬ ing cost both of the heating system and building.

It is another object of the present invention to provide a central heating system having a capability of storing heat in every individual living spaces in a simple manner, wherein the individually stored heat can be consumed for corresponding living spaces.

Still another object of the present invention is to provide a central heating system, wherein the hot water flow of the water system comprised in the system can be controlled freely by accupants of the corresponding living spaces in the building upon the temperature of the corresponding living spaces.

Still another object of the present invention is to provide a central heating system wherein the head pressure developed en the water pipes is very lew, and thus the material of wate pipes can be consist of plastics or synthetic resins regardless of the building height.

Still another object of the present invention is to provide a central heating system, wherein the steam supplied from a steam source can be utilized for other purposes such as domestic water heating, cooking or laundrying.

Still another object of the present invention is to provide a central heating system wherein the heat energy supplied to each of individual living spaces can be measured exactly and controlled upon the heat reguirement of the corresponding living spaces.

Still another object of the present invention is to provide a central heating system, wherein the most main apparatuses, pipings and the control devices of the.system can be installed on the every individual living spaces, and thus the minimum pipings and apparatuses of the system is placed in the service area, accordingly, the ownership for the system can be developed over prior central water heating system in case of apartments buildings.

Still another object of the present invention is to provide a central heating system, wherein very little power is devoted to circulating the heating medium, thus the operating cost is reduced, and servicing the system is very simple,

still another object of the present invention is to provide a central heating system wherein the thermostatic controls of the every living spaces are urged to be practiced in a automatic manner by local control. Further object of the present invention is a central heating system wherein a packaged unit can be utilized comprising the steam-to-water heat exchanges and the water circulation pumps for effective establish¬ ing and effective maintaining, in which the water circula¬ tion pumps should be controlled by a thermostat placed on return piping lines of the individually established water system, or a thermostat placed a appreciate position in the corresponding living spaces.

DISCLOSURE OF INVENTION

In accordance with the present invention a novel central Heating system is provided comprising - at least one central steam source

- a plurality of water systems established in every living spaces respectively

- said water system each comprising at least one steam-to-water heat exchanger, at least one water circula- ting pump, at least one steam supply or^"condensate discharge control means, at least one water circulating pump control means, and at least one radiator means

- said central steam source supplying steam to every heat exchanger being comprised in each of said water systems, said heat exchanger heating the water contained in said water system by said steam supply, said water circulating pump forcing the water of said water system to move from said heat exchanger interior through water supply pipings to said radiator means and from said radiator means through water return pipings to said heat exchanger again, said water circulating pump control means controlling the operation of said water circulating pump by at least one thermostat responding to the tempe¬ rature of the corresponding living space and/or the circulating water, said steam supply or condensate discharge control means controlling the interior condition of said steam-to-water heat exchanger, the steam in said system flowing from said central steam source to each of said steam-to-water heat exchangers, then being mixed with the water of said water systems, and a part of said mixed water being discharged from said water system to a condensate return pipe and returning to said central steam source.

The present invention provides also the packaged unit for using in said central heating system composed of a plurality of water systems located in every living spaces of a building respectively, said packaged unit comprising

- at least one steam-to-water heat exchanger for heating the water contained in said water systems by steam supplied from a central steam source,

- at least one heating water circulating pump for forcing the water of said water system to move from said heat exchanger through a water supply pipings to said radiator means and from said radiator means through water return pipings to said heat exchanger,

- at least one heat exchanger water level control means for controlling the heat exchanger interior condensate water level by a control means responding to said condensate water level or to the return water temperature in said water system

- at least one water circulating pump controll mean for controlling said water circulating pump operation by sensing the air temperature in said living space or the circulating water temperature in said water system

- a piping arrangement so arranged that the steam supplied to said heat exchanger is mixed with the circulating water within said water system during or after neat transmission, and a part of said mixed circulating water over-flow to said condensate return pipings. Another characteristics and adventages of the system according to present invention will become apparent from the detailed description which follows with reference to the appended drawings, provided purely by way of non- limiting example.

BRIEF DESCRIPTION OF DRAWINGS.

Figure 1 is a schematic diagram illustrating the central Heating system according to present invention, in which a plarality of water systems composing a part of present invention is described in each of separations or living spaces in a building.

Figure 2 is a schematic diagram illustrating the typical embodiment of the water system being located or established in the living spaces, in accordance with present invention.

Figure 3 is another embodiment of the water system according to present invention.

Figure 4 is a schematic diagram of the embodiment of the packaged unit, which will be cambined with the water system.

Figure 5 is another drawing of an embodiment similar to the figure 4.

Figure 6 is a schematic drawing of an other embodiment of the packaged unit which is similar to the embodiment of figure 4.

BEST MODE FOR CARRYING OUT THE INVENTION

With referance to the figure 1 the present central heating system according present invention comprises many water systems 200 in a building, which is established in every living spaces 100 respectively in the building. The system also comprises a steam boiler (10) , by which the steam is supplied through steam supply line 11, 12, 13, (or pipes) to each of the water system which is designated generally as 200 in figure 1. each of the water systems 200 comprises essencially a steam-to-water heat exchanger or exchangers 20, a water circulation pump or pumps 38, and radiators 27 or heat pannels 27. The system comprise a steam supply main line 11 with the steam supply risers 12, and a condensate return main line 16 with the condensate return risers 15. The steam supply line 11 is extending from the steam boiler 10 to the heat exchanger steam in-let 13 of every water systems 200. The condensate return line 16 is extending from an over-flow-water lines 14 through the condensate water flow meter 42 to condensate water storge tank 19 and the condensated water or the over¬ flowed water from the water system flow and return to the condensate water storge tank 19 in gravity, that is, the structure and design of the steam supply and condensate return piping is composed in accordance with the conventional opens sytem.

The water system combined with present invention is described detailly in figure 2 and 3. With referance to figure 3, the water system comprises a steam-to-water heat exchanger 20, a water circulating pump 30, a domestic hot water storge tank 32 with a heating, water circulating pump 31, a condensate water or over-flowed water flow meter 42 mounted on the condensate or over-flowed water return line 14, a circulating water supply or distribution Header 25 distributing the hot water to each of the radiators 27, a circulating water return or recieving Header 29 recieving the cooled water from each of the radiators 27, and five radiator 27. The water system 200 also comprises a steam trap 38 mounted on the pipe line 22 toward the heat exchanger water in-let. The circulation pump 30 is mounted on the water line 22 extending from the circulating water distribution header 29 to the heat exchanger water in-let. The system also comprises an adjusting valve 38 which is mounted on the line extending between the pipe line 22 connecting the circulation pump dischange to heat exchanger water- in-let and the pipe line 24 connecting the heat exchanger water out-let to the circulating water distribution header 25.

The water pipe lines are forming a plurality of water loops running from the discharge of the circula¬ tion water pump 30 through in turn, the heat exchanger water in-let, the circulating water distribution header 25, each of radiators 27, the circulating water receiving header 4, and to the water circulation pump suction 30.

With referance to figure 2 and 3, the steam supply line 13 is connected to the steam in-let of the heat exchanger 20 and the condensate water line is extending from a pipe line 22 extending between the water circula- ting pump out-let and the heat exchanger water in-let. Mounted on the pipe line extending from heat exchanger steam out-let to the pipe line 8 is a steam trap 38. The steam trap 38 prevents the steam from flowing out of the heat exchanger condensate out-let to the heat exchanger water in-let, while the steam trap 38 permits the conden- sated water in the heat exchanger to flow-out to the heat exchanger water in-let, thus the steam supplied from the central steam boiler 10 to each of heat exchangers 20 located in every living spaces 100 of the building flows into the heat exchanger inner space through the heat exchanger steam in-let, then the steam is cooled by the water coil 23 extending from the water in-let to water out-let in the inner space of the heat exchanger 20. As a result of this, the steam changes it's phase to liquid. The phase changed water from steam to water is flowing with steam to the steam trap through the Heat exchanger condensate water out-let. The steam trap separates condensate water from steam and allow the condensate water to flow to the heat exchanger water in-let, while prevent the steam from flowing to the Heat exchanger water in-let. The condensated water which passed the steam trap 38 is introduced to and flows along the water loops of the water systems.

As illustrated in figure 2 and 3, the circulating loop of the water systems is opened only toward the steam supply line or steam trap discharge and the condensate return line 14. Accordingly,the introduction of condensate water to the water system causes the circulating water over-flowing through the condensate water return line 14. The check valve 55 mounted between the introduction point of the condensate water to the water system and the over¬ flowing point of the circulating water to condensate return line 14 prevents the condensate water from flowing directly to the condensate return line 14.

The pump 30 is a line type pump and has relatively small size and capacity, which is for example, a line pump having power less than 1/10 house power. The pump 30 may be a line pump having a power less than 1/30 house power. The operation of the pump 30 is practiced by a room thermo-stat. The wiring between the thermo-stats and the circulation pump is so arranged that when the thermo-stat located in a room sense a higher tenperature than the higher pre-set temperature of the thermo-stat, the water circulating pump 30 is off and when the thermo-stat located in said room senses a lower temperature 4 than the lower pre-set temperature of the thermo-stat, the water circulating pump 30 is on.

As a result of the arrangement described above,the steam supplied from the central boiler 10 can flow to heat exchanger only when the water circulating pump 30 is operating, and the condensate water can flow out from the water system after passing through at least one of the water loop of the water system. In present invention the water circulating pump 30 is operated by the thermo- control means such as room thermo-stat which is located on a room or separations, which the corresponding circulating pump is covering.

Referring to figure 1 again the system of figure 1 comprises many examples of present invention showing the combination of the heat exchanger and the water circulat¬ ing pumps or the combination of the heat exchanger and the domastic hot water storge tank, or the combination of the water circulation pumps and the radiator or pannel coil. The figure 1 also explains that the water system are established covering one or two stairs, and that the water systems are covering an area which is a living space and is responsable to maintain by an occupant.

The flow adjusting valves 37 adjusts the heat water temperature flowing through the radiator 27 in the manner of by-passing the water flow between the heat exchanger water in-let and heat exchanger water out-let. This provides comportable heating condition in the subjected rooms. The water flow meter 42 positioned on the condensate water return line 14 meters the volume rate of the over¬ flowing water from the water system. The over-flowing water weight is equal to the weight of the supplied steam to the water system, thus the volume rate metering of the over-flowing water has the same effect of the metering the calories of the introducing steam to the heat exchanger 20 because the steam pressure on the introducing point to heat exchanger is almost equal to each other and the temperature of the returning condensate water to the central boiler is very low which reduce extermely the heat loss developed during the condensate water returning. The over-flowed water volume is typically proportional to the heat consumption of the water system of every living space.

More ever, the system has an out-standing advantage that all the devices except rediator comprising heat exchanger, circulation pump and steam trap can be integrated in a package, and the packaged unit has very small size, for example a size 0.4 x θ.8 x 0.25 in metrics. hus the packaged unit can be mounted an any suitable ^'space, such as on a well of a kitchen or on a wall of a bath room or in the sealing of a office room.

The example of packaged unit emboding the integration is illustrated in figure 4, 5 and 6.

The example of the packaged unit of figure 4 comprises a heat exchanger 20, a water circulating pump 30, a steam trap 38, and two water Header 29 each having six branches. All the element described above are contained in the encloser 60, and all the element except the pump motor 30,including connecting pipes are insulated with glass wools or rock wools 62 The flow of water or steam in the package is same to the description of the water system discribed above.

.Another example of the packaged unit according to present invention is illustrated in figure 5. The packaged unit of figure 5 comprises the same element except the heat exchanger andsteam trap with figure 4. In figure 5, the heat exchanger is displaced from a conventional water tube or coil type heat exchanger to a conventional direct contact heat exchanger, thus a solenoid valve 40 is mounted on the steam supply line, and the sensor 47 for controlling the solenoid valve is a temperature sensor so that the solenoid valve is open when the temperature in the Heat exchanger is lower than a predetermined temperature or setting temperature,thus the water tempera¬ ture in the Heat exchanger is maintained constantly. In this example, the sensor may be a float switch sensing the water level in the Heat exchanger.

The example of figure 6 is illustrating the use of the float valve instead of the solenoid combined with a float switch or a temperature sensor.

Though the examples of figure 4, 5 and 6 have some differences,particulary in structure, the principle of the steam and water flow is the same in that the steam supplied from the central boiler is mixed finally to the circulating water of the water system and is returned to the central steam boiler.

Additionally,it may be posible that the water system comprise a plarality of water circulating pumps (figure 2) However loop length of the water system may be less than 100m. As an alernative of the condensater water flow meter, it is posible that the water system comprises a steam flow meter 42, mounted on the steam supply pipe branch 13 to heat exchanger,provided that a steam presure regulating valve sould be provided on the steam supply pipe 13 before the steam flow meter.

INDUSTRUAL APPLICAPABILITY

As described above the water circulating loop length of the present system is very short over prior water systems or combined steam and water system. Accordingly, the power for water circulating may be very small, which is about 10-40% over the prior Art.

Further more, all the elements comprising the steam trap, the water circulation pump, the room thermo-stat the temperature senser, the float switch, and the float valve, can be available commercially and are all mass producted goods except the heat exchanger body, thus the products can be provided cheaply. Accordingly the system utilizing such products can be established in a low cost. According to the applicants estimate, the establishing cost of the system is considerably lowed over prior four-pipe water system, especially applied to a large scale building or an a.partment building

Further more, the head pressure developed an the water line of the water system is very low, thus it is posible that the synthetic resin or plastic materials can be utilized for the water piping material

Further more, the servicing of the system is very simple by displacing the elements since the parts of the system may be all mass producted, and the maintaince of the system also can be accomplished in a low cost. The system is running in a local control system, thus the system can provide the most optimum and the most economic heating condition.

Although the preferred and alternative embodiments have been described, it will be apparent to one skilled in the Art that changes can be made therein without departing from the scope of the invention.

Claims

CLAIM

1. In the central heating system supplying heat from a central heat source or sources to every living spaces of a building or buildings, the central heating system comprising

- at least one central steam source

- a plurality of water systems established in every living spaces respectively - said water system each comprising at least one steam-to-water heat exchanger, at least on water circula¬ ting pump, at least one steam supply or condensate discharge control means, at least one water circulating pump control means, and at least one radiator means - said central steam source supplying steam to every heat exchanger comprised in each of said water systems, said heat exchanger heating the water contained in said water system said water circulating pump forcing the water of said water system to move from said heat exchanger interior^*through water supply pipings to said radiator means and from said radiator means through water return pipings to said heat exchanger again, said water circulating pump control means controlling the operation of said water circulating pump by at least one thormostat responding to the tempera¬ ture of the corresponding living space and/or the circula¬ ting water, said steam supply or condensate discharge control means controlling the interior condition of said steam-to-water heat exchanger, the steam in said system flowing from said central steam source to each of said steam-to-water heat exchangers, then being mixed with the water of said water systems, and a part of said mixed water being discharged from said water system to a condensate return pipe and returning to said central steam source.

2. A central heating system according to claim 1, further comprising water flow meters mounted on every condensate water discharge pipings from the water systems.

3. A central heating system according to claim 1, further comprising steam flow meters mounted on every steam supply pipings to said water systems.

4. A central heating system according to claim 1, wherein each of said living spaces comprises at least one room of apartments, Hotels dormitories "or offices .

5. A central heating system according to claim 1, wherein said steam-to-water heat exchanger is a single- path tabular steam-to-water heat exchanger and said steam supply or condensate discharge control means is a steam trap.

6. A central heating system according to claim 1, wherein said steam-to-water heat exchanger is a direct contact heat exchanging type in which the steam contact directly with circulating water by which steam transmit heat to the water, and said steam supply or condensate discharge control mean is an automatic valve being operated by the buoyancy of a float combined with said valve and positioned in said heat exchanger interior.

7. A central heating system according to claim 1, wherein said steam-to-water heat exchanger is a direct contact heat exchanging type in which the steam contact with circulating water by which steam transmit heat to the water, and said steam supply or condensate discharge control mean is a water flow control valve positioned on said steam supply piping connected to said heat exchangers or positioned on said condensate discharge piping extending from said heat exchangers, said water flow control valve being actuated by sensing the water temperature or the water level in the heat exchanger, which is so arranged that when the water temperature or the water level in the heat exchanger is lower than a predetermined setting point the valve is open and when the water is in the other condition the valve is closed.

8. A central heating system according to claim 1, wherein said water circulating pump-control mean is a thermostat or thermostats arranged in series with said circulating pump, and positioned on an appricate place or places in said living spaces, so that when the temperature in said living space is lowed below a predeter¬ mined set-point, said water circulating pump is operating and when the temperature in said living sapce is rised above a higher predetermined set-point, said circulating pump stops it's operation.

9. A central heating system according to claim 8, wherein said water circulating pump control mean further comprises another thermostat which turn on the water circulating pump only when the water temperature in the exchanger is higher than a predetermined set-point and which thermostat is wired in series with said thermostat or thermostats.

10. A central heating system according to claim 1, wherein each of said water system further comprises a domestic hot water heating means including a water circulation loop communicating the domestic hot water storge tank with said heat exchanger.

11. A central heating system according to claim 1, wherein each of said water system further comprises a high temperature water storge tank, the lower positioned water in-let of which is communicating with said heat exchanger water out-let, and the upper positiond water out-let of which is communicating with a pipe line extending to said radiator means.

12. A packaged unit for using in a central heating system composed of a plurality of water systems located in every living spaces of a building respectively, said packaged unit comprising

- at least one heating water circulating pump for forcing the water of said water system to move from said heat exchanger through water supply pipings to said radiator means and from said radiator means through water return pipings to said heat exchanger,

- at least one heat exchanger water level control mean for controlling the heat exchanger interior conden¬ sate water level by a control means responding to said condensate water level or to the return water temperature in said water system

- at least one water circulating pump control mean for controlling said water circulating pump operation by sensing the air temperature in said living space or the water temperature in said wate system.

- a piping arrangement so arranged that the steam supplied to said heat exchanger is mixed with the circulating water within said water system during or after heat transmission, and a part of said mixed circulating water over-flow to said condensate return pipings.

13. A packaged unit according to claim 12, wherein said water circulating pump has a power less than 1/10HP.

14. A packaged unit according to claim 12, wherein said steam-to-water heat exchanger is a single-path tabular steam-to-water heat exchanger, and said heat exchangerwater level control mean is a steam trap.

15. A packaged unit according to claim 12, wherein said steam-to-water heat exchanger is a direct contact heat exchanger, and said heat exchanger water level control mean is an automatic valve being operated by the buoyancy of a float combined with said valve and positioned in said heat exchanged interior.

16. A packged unit according to claim 12, wherein said steam-to-water heat exchanger is a direct contact heat exchanger, and said heat exchanger water level control mean is a water flow control valve positioned on said steam supply piping to said Heat exchangers or positioned on said condensate discharge piping from said heat exchangers, said water flow control valve being actuated by sensing the water temperature or the water level in the heat exchanger, which is so arranged that when the water temperature or the water level in the heat exchanger is lower than a predetermined setting point, the valve is open and when the water is in the other condition the valve is closed.