JPH10205790A - Hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate a maintenance and cleaning of a hot water supply system, reduce a space occupied by the system and enable an installation of the system underground or at a lower floor, wherein hot water in an atmospheric pressure open type temperature elevation hot water storage tank is pressurized and supplied to a hot water spout while a heating control is carried out on the temperature of hot water which flow in a supply pipe and a hot water return pipe. SOLUTION: Hot water heated by an atmospheric pressure open type temperature elevation hot water storage tank 70 flows in a pipe 4 and is pressurized by a pressurizing pump 3. The pressurized hot water has its pressure reduced to a given pressure by a pressure reducing valve 16 and is supplied to a water supply pipe 41. The hot water supplied to the water supply pipe 41 reaches a hot water return pump 43 by way of hot water spouts 42a-42d. The hot water return pump 43 circulates the return hot water by making the return hot water pass through a heat exchanger 5 by way of a return hot water pipe 44. During this circulation, the return water is heated by the heat exchanger 5. Controllers 27, 28 control the return pump 43 and the circulation pump 7 and controls the hot water supply at an approximately constant temperature. This temperature is almost equal to the temperature of the hot water supplied and stored in the atmospheric pressure open type temperature elevation hot water storage tank 70.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention belongs to the technical field of a hot water supply system. More specifically, the present invention relates to a technical field of a central management type hot water supply system using an atmospheric pressure open type hot water storage tank.

[0002]

2. Description of the Related Art Conventionally, a hot water supply system has a scale,
Various types of systems have been proposed depending on the application. As a large-scale hot water supply system used in a building, for example, a large heater such as a hot water boiler or a hot water storage tank is installed in a machine room of a building, and when a hot water tap of an appliance is opened, hot water of a uniform temperature is immediately discharged. In order to reduce the heat loss in the piping, a hot water supply pipe and a return water pipe are provided, and the hot water from the hot water storage tank is supplied at the water supply pressure and forcedly circulated using a circulation pump. It has been used for some time. In addition, various types of hot water supply systems have been proposed. Hereinafter, a conventional hot water supply system which is considered to be closest to the present invention will be described.

FIG. 3 shows an example of such a conventional hot water supply system (hereinafter, referred to as conventional system 1). In FIG. 3, the hot water boiler 31 is, for example, a pressureless open boiler or a vacuum heater. The water in the hot water boiler 31 is heated by a heating source 32 such as a burner, and the heated high-temperature hot water passes through a hot water pipe 33, passes through a heating coil 30 provided in a hot water storage tank 34, and is circulated by a circulation pump 35 and hot water. It returns to the hot water boiler 31 via the pipe 36. The hot water storage tank 34 is a closed type tank, and a hot water supply port 37 is provided at the head, and a hot water supply port 38 and a water supply port 39 are provided at a lower portion. Further, a safety valve 40 is provided at an appropriate position of the hot water storage tank 34.

Hot water flowing out of a hot water supply port 37 flows through a hot water supply pipe 41 to which hot water taps 42 a to 42 d such as a shower head and a curan are connected.
4, the water returns to the hot water storage tank 34 from the hot water return port 38. The hot water supply pipe 41 is provided with an expansion tank 46.
This absorbs pressure fluctuations when the pressure rises or falls due to a change in the water temperature in the hot water supply pipe, and prevents the pressure above the allowable value from acting on the pipe.

[0005] The water supply pipe 47 is connected to a tap (not shown) or the like, and is supplied from the water supply port 39 when the amount of hot water in the hot water tank decreases. A temperature detector 49 is provided near the water supply port of the hot water storage tank 34, and its output is connected to an input terminal of the controller 48. Controller 48
Are connected to the output terminal burner 32 and the circulation pump 35. The controller 48 controls the circulation pump 35 and the flow control valve 52 based on the hot water supply temperature detected by the temperature detector 49. The burner 32 is controlled based on the boiler water temperature.

[0006] A temperature detector 51 for detecting the temperature of the hot water.
Is provided downstream of the hot water pump 43, and the output of the temperature detector 51 is connected to the input terminal of the controller 50. The output end of the controller 50 is connected to the hot water pump 43. The controller 50 activates the hot water pump 43 when the temperature of the hot water in the hot water pipe 44 drops, and maintains the hot water temperature in the hot water supply pipe 41 and the hot water pipe 44 constant.

The conventional system 1 operates as follows with the above configuration. That is, the hot water tank 34 is filled with hot water in a pressurized state by the pressure of the water supply pipe 47. The water in the hot water storage tank is heated by hot water from a hot water boiler
The heated hot water is supplied from the hot water supply port 37 to the hot water tap 42 through the hot water supply pipe 41. Hot water tap 4
When the hot water is used in 2 and the hot water in the hot water tank decreases, the water supply pipe 4
Water is supplied from 7, and a predetermined amount of hot water is stored.

The temperature of the hot water is detected by a temperature detector 49, and the controller 48 outputs an ON signal to the circulation pump 35 to circulate the hot water to heat the hot water in the hot water storage tank to a predetermined temperature. Hot water in the hot water boiler 31 is maintained at a high temperature by igniting the burner 32 by on / off control or schedule control. In addition, when the temperature of the hot water in the hot water pipe falls due to long-time non-use, the temperature is detected by the temperature detector 51, and the controller 50 outputs an ON signal to the hot water pump 43 to send the hot water pipe 41 and the hot water pipe. Circulate 44 hot water. As a result, the hot water in the hot water supply pipe 41 and the hot water return pipe 44 is
4 is equal to the temperature of the hot water. As a result, the hot water supply temperature is maintained at the predetermined temperature.

FIG. 4 shows another hot water supply system (hereinafter referred to as conventional system 2), which is almost the same as conventional system 1.
The main difference is that a steam boiler 60 is used instead of a hot water boiler. Hereinafter, the different points will be described. The same parts are denoted by the same reference numerals and the description is omitted. The high-temperature steam heated by the steam boiler 60 flows through the pipe 61 to the heating coil 62, where water droplets condensed by the trap 63 are separated, and the condensed water returns from the pipe 64 to the steam boiler 60. The controller 65 controls the flow control valve 67 based on the temperature of the temperature detector 49. The burner 32 is controlled by the internal pressure of the steam boiler.

The hot water supply pipe 41 is provided with an open type expansion tank 66, which functions in the same manner as the closed type expansion tank 46 in the conventional system 1. Therefore,
A closed expansion tank may be used instead of the open expansion tank. The conventional system 2 is configured as described above, and its operation is the same as that of the conventional system 1, and the description is omitted.

FIG. 5 shows an example of a conventional hot water supply system using an atmospheric pressure open type hot water storage tank (hereinafter referred to as conventional system 3). The same components as those of the conventional systems 1 and 2 are denoted by the same reference numerals, and detailed description is omitted. In FIG. 5, the atmospheric pressure open-type warmed hot water storage tank 70 is installed at the LL level above all the hot water taps 42a to 42d, for example, on the upper floor of a building. A hot water supply pipe 71 is connected to the atmospheric pressure open type hot water storage tank 70, and hot water flowing through the hot water supply pipe 71 is connected to each of hot water taps 42 a to 42 d. It returns to the atmospheric pressure open-type warmed hot water storage tank 70 through 73.

The hot water in the atmospheric pressure open type hot water storage tank 70 is heated by a heating source 74 such as an electric heater or a combustion burner.
The water level of the hot water in the hot water storage tank 70 is detected by the level detector 75, and the water level signal is sent to the controller 76. The controller 76 sends a control signal to the flow control valve 77 disposed in the water supply pipe 82 based on the water level signal, and controls the amount of water supplied so as to keep the level of the hot water constant. Boiler 70
The temperature of the hot water inside is detected by a temperature detector 78, and a temperature signal is sent to a controller 79. The controller 79 controls the heating means 74 based on the temperature signal to maintain the hot water temperature constant. Hot water temperature detector 80 arranged in hot water pipe 73 detects hot water temperature in hot water pipe 73 and sends a temperature signal to controller 81. Controller 81 controls the operation of hot water pump 72 based on this temperature signal.

The conventional system 3 is configured as described above, and operates as follows. That is, the hot water heated to a constant temperature by the heating source 74 descends in the hot water supply pipe 71 by gravity and flows out of the hot water taps 42a to 42d. When all the hot-water taps are closed, they stay in the hot-water supply pipe. In this case, the temperature of the hot water drops due to natural heat radiation, and the controller 81 operates the hot water return pump 72 to circulate the hot water in the pipeline. Further, the temperature and the water level of the hot water in the atmospheric pressure open type hot water storage tank 70 are kept constant by the controllers 79 and 76.

[0014]

As described above, in the hot water supply system using the closed type hot water storage tank as in the conventional systems 1 and 2, the structure of the boiler itself becomes complicated, and maintenance and internal operations are not performed. There is a problem that cleaning is difficult, and in some cases, special education and qualifications are required for the boiler driver, and there is also a problem in securing personnel. In addition, maintenance and cleaning of hot water tank are difficult,
This was a problem because it needed to be inspected as a pressure vessel. Furthermore, since both the boiler and the hot water tank are installed, there are problems in terms of space and installation cost.

In a conventional hot water supply system using an open-air temperature rising hot water storage tank such as the conventional system 3, since a downward hot water supply system is adopted, it is necessary to install a hot water storage tank on an upper floor. In addition, there is a problem that the weight of the open-air temperature rising hot water storage tank during operation becomes heavy to store hot water, and the structure of the building must be strengthened, which increases construction costs. In particular, there was a major issue in increasing the earthquake resistance against earthquakes.

SUMMARY OF THE INVENTION The present invention has been made under the above background, and has as its object to provide a hot water supply system which is easy to maintain and clean, has a small space requirement, and can be installed in an underground or lower floor. And

[0017]

Means for Solving the Problems In order to solve the above-mentioned problems, the hot water supply system of the present invention comprises the following means. That is, the hot water supply system according to claim 1 includes a circulating hot water passage connected to a hot water tap provided at an appropriate place in the building;
A pressurizing supply means for providing a branch pipe in the hot water supply pipe of the circulation hot water path, and for pressurizing and supplying hot water from an atmospheric pressure open type hot water storage tank;
A hot water pump is provided in the hot water pipe of the circulation hot water path, and a heating control means for heating hot water of the hot water pipe to control hot water supply temperature. In the hot water supply system according to this mode, hot water in an atmospheric pressure open-type warmed hot water storage tank is pressurized by pressurizing supply means to forcibly supply hot water to a hot water tap connected to a hot water supply pipe. Further, the temperature of the hot water in the hot water supply pipe and the hot water return pipe is controlled by heating control means.

Further, in the system according to the second aspect, the heating control means in the first aspect circulates the hot water from the atmospheric pressure open type warmed hot water storage tank to the primary side of the heat exchanger and to the secondary side. The method is characterized in that the return of hot water is circulated and the flow of hot water on the primary side is controlled to control the hot water supply temperature at an appropriate temperature. The hot water supply system of this section utilizes the hot water in the open-air heating type hot water storage tank to heat the hot water in the hot water supply pipe and the hot water return pipe.

According to a third aspect of the present invention, as a control by the heating control means according to the first or second aspect, the temperature of the secondary outlet of the heat exchanger is detected, and based on the detected temperature,
It is characterized in that the flow rate of the hot water on the primary side is controlled.

The system according to the fourth aspect is the system according to the first aspect.
The system according to claim 3, wherein the pressurizing and supplying means includes a hot water supply pump, a check valve, and a pressure reducing valve. The hot water supply system of this section pressurizes hot water from an atmospheric pressure open type hot water storage tank with a hot water supply pump, supplies hot water to the hot water supply pipe from the branch point of the branch pipe, and supplies hot water to the hot water supply pipe even when the operation of the hot water supply pump is stopped. To prevent backflow.

According to a fifth aspect of the present invention, there is provided a hot water supply system, wherein the pressurizing / supplying means according to the first to fourth aspects includes a pressure detecting means for detecting a secondary pressure, and controls the hot water supply pump based on the detected pressure signal. It is characterized by being controlled. In the hot water supply system of this section, hot water supplied to the hot water supply pipe is controlled to a predetermined pressure.

A hot water supply system according to a sixth aspect of the present invention further includes a water level in the open-to-atmosphere type hot water storage tank and a water intake level of each pump based on the detected water level. When the water level falls below a certain level so as not to fall below a predetermined value, the pump is stopped, the pump is prevented from running idle, and a system for protecting the pump is provided. The hot water supply system of this section further includes a pump protection system.

A hot water supply system according to a seventh aspect of the present invention is the hot water supply system according to the first to sixth aspects, further comprising detecting a temperature in the open-air type warmed hot water storage tank and, when the temperature becomes abnormally high, from a heating source. The system is provided with a system for stopping the heating of the hot water tank, stopping the pump taking water from the hot water tank, and protecting the hot water tank, the pump and the piping.

[0024]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of an embodiment of the present invention. FIG. 2 is a detailed view in which main parts of the present embodiment are enlarged for explanation. Hereinafter, the same components as those already described in the description of the conventional system are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIGS. 1 and 2, an atmospheric pressure open-type warmed hot water storage tank 70 is placed on a gantry 2 on the floor of a basement or on the ground. The upper side of the open-pressure warmed hot water storage tank 70 is covered with a cover (not shown). A heating source 74 such as an electric heater is provided in the atmospheric pressure open type hot water storage tank 70, a water supply pipe 82 is connected, and a pipe 4 is connected to the pressurizing pump unit 3. .

To the primary side heating pipe 5a of the heat exchanger 5, pipes 6, 6 for circulating and flowing high-temperature hot water from an atmospheric pressure open type hot water storage tank 70 are connected. A circulation pump 7 is provided on the pipe 6 to circulate the hot water in the pipe 6. The output of the water level detector 75 is connected to the input terminal of the controller 8, and the output terminal of the controller 8 is connected to the flow control valve 77 in order to control the water level of the open-pressure warmed hot water storage tank 70 to be constant. , Controlling the flow rate.

The water level detector 75 is composed of an electrode rod, a float switch or the like. In addition to performing control to keep the water level constant, the controller 8 also performs alarm control when the water level becomes abnormally low due to occurrence of some abnormality. That is, when an abnormal water level is detected by the water level detector 75, the controller 8 alerts the operator of the abnormal water level. When an abnormally low water level is detected, the pump is stopped to prevent idling.

Further, a hot water temperature detector 9 for detecting the temperature of the hot water stored in the open-air temperature rising hot water storage tank 70 and a thermostat 10 for detecting an abnormal rise in the temperature of the hot water are provided. These outputs are connected to input terminals of the controller 11, and output terminals of the controller 11 are connected to control terminals of the electric heater 74. In addition to controlling the hot water storage temperature to be constant, the controller 11 is programmed to completely turn off the electric heater 74 when the thermostat 10 detects an abnormal temperature. If it is completely turned off, an abnormal temperature alarm will be issued. Even if the temperature of the hot water drops, the electric heater 74 is kept off.

The pressure pump unit 3 includes the pressure pump 1
3, a check valve 14 and a pressure sensor (may be a pressure switch) 15. The pressurizing pump 13 pressurizes hot water supplied from the atmospheric pressure open-type warmed hot water storage tank 70 and supplies the hot water to the pipe 23. The pressure sensor 15 detects the internal pressure of the piping of the pressure pump 13, inputs a detected pressure signal to the controller 18, and the controller 18 controls the pressure pump 13 so that the discharge pressure is substantially constant. This control may be on / off control or other control. Check valve 14
Prevents the backflow of hot water supply from the pipe 23. Pressurizing pump 1
3 stops, the output pressure of the pump 13 also decreases,
The check valve 14 prevents backflow.

A pressure reducing valve 16 is provided in a pipe 23 downstream of the pressure pump unit 3, and the output side of the pressure reducing valve 16 is connected to the hot water supply pipe 4.
1 connected. The pressure of hot water supply from the pressurizing pump unit 3 varies depending on whether the pressurizing pump is operating or stopped.
The pressure fluctuates. The pressure reducing valve 16 eliminates this pressure fluctuation and supplies hot water at a constant pressure to the hot water supply pipe 41. That is, if there is a pressure fluctuation on the hot water supply side, when a mixing tap is used, the balance between the pressure of the hot water tap and the pressure of the water tap will be disrupted, and the temperature of the mixed hot water will fluctuate, which is undesirable. ing.

Downstream of the pressure pump unit 3, the pressure reducing valve 1
A branch pipe 19 is provided in a pipe 23 upstream of the pipe 6, and a safety valve 20 is provided in the branch pipe 19. An escape port side of the safety valve 20 is connected to an appropriate position above an atmospheric pressure open type temperature-raising hot water storage tank 70 by a pipe 21. Therefore, when the output pressure of the pressurizing pump unit 3 becomes abnormally high, the safety valve operates to release the high-pressure hot water to the atmospheric pressure open type warmed hot water storage tank and reduce the pressure. It prevents the pressure from rising to dangerous levels. Note that a relief valve may be used instead of the safety valve 20.

The secondary side 5b of the heat exchanger 5 is
The hot water flowing from the hot water supply pipe 44 flows out of the hot water supply pipe 41 after being heated by the heat exchanger 5. Hot water temperature detectors 24 and 25 for detecting the hot water temperature are provided at the inlet and outlet on the secondary side of the heat exchanger 5. The output of the hot water temperature detector 24 is connected to the input terminal of the controller 27, and the output terminal of the controller 27
3 is connected to the control end. When the temperature of the hot water in the hot water pipe 44 decreases, the controller 27 operates the hot water pump 43 to circulate the hot water in the hot water pipe 44 and the hot water supply pipe 41 and to circulate the heat in the heat exchanger 5. Heat the circulating water.

On the other hand, the output of the hot water temperature detector 28 is connected to the input terminal of the controller 28, and the output terminal of the controller 28 is connected to the control terminal of the circulation pump 7. When the secondary outlet temperature of the heat exchanger 5 is low, the controller 28 operates the circulation pump 7 to increase the temperature of the hot hot water flowing through the heating pipe 5a. Further, a closed type expansion tank 46 is provided in the hot water supply pipe 41 or the hot water return pipe 44 to suppress a rise in pressure in the pipes 41 and 44 due to a temperature change of the hot water supply to an allowable value or less. Note that an open expansion tank may be provided above the pipe 41 instead of the closed expansion tank.

This embodiment is configured as described above, and operates as follows. That is, the hot water heated in the atmospheric pressure open type hot water storage tank 70 flows through the pipe 4, is pressurized by the pressurizing pump unit 3, is reduced to a predetermined pressure by the pressure reducing valve 16, and is supplied to the hot water supply pipe 41. . Hot water supply pipe 41
Is supplied to the hot water return pump 43 via hot water taps 42a to 42d. Hot water return pump 43 passes hot water through heat exchanger 5 and circulates in the direction of the arrow in FIG. During this circulation, the hot water is heated by the heat exchanger 5. Controller 2
7 and 28 control the hot water pump 43 and the circulation pump 7 to control the hot water supply to a substantially constant temperature. This temperature is substantially equal to the temperature of the hot water in the atmospheric pressure open type hot water storage tank 70.

When hot water is used from the hot water taps 42a to 42d, the pressure in the hot water supply pipe decreases, and as a result, the secondary (output) pressure of the pressure reducing valve 16 also decreases. When the primary pressure of the pressure reducing valve 16 decreases, this pressure decrease is detected by the pressure sensor 15, and the controller 18 turns on the pressurizing pump 13 to supply hot water from the atmospheric pressure open type temperature rising hot water storage tank. Therefore, when hot water is used, hot water is replenished from the atmospheric pressure open-type heated hot water storage tank 70 by the pressure pump unit 3.

When the hot water supply is used, the water level in the open-air heating type hot water storage tank 70 drops, and the decrease in the water level is detected by the water level detector 75.
7 is opened and the amount of hot water is replenished and maintained substantially constant. The temperature of the hot water in the atmospheric pressure open-type warmed hot water storage tank 70 decreases due to the water supply and natural heat radiation. This drop in temperature is detected by the hot water temperature detector 9, and the controller 11 turns on the heating source 74 based on this drop in temperature, and the temperature in the atmospheric pressure open type hot water storage tank is kept substantially constant.

As described above, the hot water supply system of this embodiment is normally well controlled. Also, when an abnormality occurs, for example, the amount of hot water used becomes abnormally large,
When the water supply to the atmospheric pressure open-type warmed hot water storage tank 70 is stopped, etc., and the water level drops abnormally, the controller 8 issues an alarm and stops the heating source 74, the pump 3 and the pump 7. I do. Further, when the temperature in the atmospheric pressure open-type warmed hot water storage tank 70 rises abnormally, the controller 11 issues an abnormality alarm and turns off the heating source 74 to prevent occurrence of a dangerous state. When the hot water supply pressure supplied to the hot water supply pipe 41 rises abnormally, the safety valve 20 is opened to prevent occurrence of a dangerous situation.

The embodiments and examples of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the examples, and changes in the design and the like may be made without departing from the gist of the present invention. Even if there is, it is included in the present invention. For example, the controller may be entirely controlled by one computer instead of being provided separately. Further, when a throttle valve is used instead of the pressure reducing valve 16, the performance is inferior to that of the above embodiment, but belongs to the scope of the present invention. Further, the control method is not limited to the above-described method, and another method may be adopted. Further, the atmospheric pressure open-type warmed hot water storage tank is not limited to being installed in a basement or on the ground, but may be installed on the second or third floor depending on other circumstances.

This embodiment has the following effects because it has the above-described configuration and operation. In other words, since the hot-water storage tank with open-air pressure is used and hot water is supplied by means of pressurized water supply, it can be installed in basements or outdoors. Installation is easy without the need for strengthening, and construction and installation costs are reduced. Since the open-pressure warmed hot water storage tank also serves as a hot water storage tank and a boiler, the entire apparatus becomes compact. Further, maintenance, cleaning and the like of the entire apparatus become relatively easy. Also,
The absence of legal regulations and this makes it easier to secure personnel without requiring special training and qualifications for operators.

Further, there is no high-pressure part in the whole apparatus, and handling is easy, and there is no need to inspect the pressure vessel. Water level control, temperature control, and pressure control are performed to prevent the occurrence of abnormal situations.In addition, when an abnormal situation occurs, a warning is issued, and control is performed to notify the operator and stop operation. Therefore, safe driving operation is possible.

[0041]

As described above, according to the structure of the present invention, the invention according to claim 1 uses an atmospheric pressure open type warmed hot water storage tank and supplies hot water by pressurized supply means. The restrictions on the installation location are loose. Therefore, there is an effect that it is easy to secure the installation place. In addition, if it is installed in a basement or outdoors, the structure of the building becomes simpler and measures against earthquakes become easier, so that there is an effect that the building construction cost and installation work cost are reduced. Since the open-pressure warmed hot water storage tank also serves as a hot water storage tank and a boiler, the whole apparatus is compact and maintenance and cleaning become easy.

According to the second and third aspects of the present invention, since the hot water of the boiler is used as the heat source of the heat exchanger, no separate heating source is required, and the equipment cost and the operating cost are low. This has the effect of making the device compact.

According to the fourth aspect of the present invention, a check valve is connected to prevent backflow even when the operation of the hot water supply pump is stopped, so that the pressure in the hot water supply pipe is reduced even when the hot water supply is not used for a long time. Since there is no hot water supply, there is an effect that the supply of hot water can be performed smoothly.

The invention according to claim 6 or 7 is provided with a protection system against occurrence of an abnormal situation, so that there is an effect that safe operation becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of the embodiment of FIG. 1;

FIG. 3 is a diagram showing an example of a conventional hot water supply system.

FIG. 4 is a diagram showing an example of another conventional hot water supply system.

FIG. 5 is a diagram showing an example of another conventional hot water supply system.

[Explanation of symbols]

 Reference Signs List 3 pressure pump unit (pressure supply means) 5 heat exchanger (heating control means) 7 circulation pump (heating control means) 8 water level controller 11 temperature controller 13 pressure pump (hot water supply pump) 14 check valve 15 pressure sensor 16 Pressure reducing valve 20 Pressure safety valve 27 Hot water supply pump controller 28 Circulation pump controller 41 Hot water supply pipe (circulation hot water path) 42a to 42d Hot water tap 43 Hot water supply pump 44 Hot water supply pipe (circulation hot water path) 46 Closed expansion tank 70 Atmospheric pressure open type lift Hot water storage tank 74 Electric heater (heating source) 75 Water level detector 77 Flow control valve

Claims (7)

[Claims] 1. A circulating hot water channel connected to a hot water tap provided at an appropriate place in a building, and a branch pipe provided in a hot water supply pipe of the circulating hot water channel, so as to allow a hot water storage tank to be opened from the atmospheric pressure type. The system includes pressure supply means for pressurizing and supplying hot water, a hot water pump provided in a hot water pipe of the circulation hot water path, and heating control means for heating hot water in the hot water pipe and controlling hot water temperature. A hot water supply system characterized by: 2. The heating control means circulates the hot water from the open-air pressurized hot water storage tank to the primary side of the heat exchanger, circulates the returning hot water to the secondary side, and controls the flow rate of the primary side hot water. The hot water supply system according to claim 1, wherein the hot water supply temperature is controlled so as to be maintained at a constant temperature. 3. The control of the heating control means includes detecting a secondary outlet temperature of the heat exchanger, controlling a primary hot water flow rate based on the detected temperature, and controlling the secondary temperature of the heat exchanger. 3. The hot water supply system according to claim 1, wherein the inlet temperature on the side is detected, and the return flow rate on the secondary side is controlled based on the detected temperature. 4. 4. The hot water supply system according to claim 1, wherein the pressurizing / supplying means includes a hot water supply pump, a check valve, and a pressure reducing valve. 5. The hot-water supply means includes a pressure detection means for detecting a downstream pressure of the hot water supply pump, and controls the hot water supply pump on and off based on the detected pressure signal. The hot water supply system according to claim 1. 6. The hot water supply system further detects a water level in the open-air warming hot water storage tank, and based on the detected water level, the water level falls below a certain level so as not to fall below the intake water level of each pump. The hot water supply system according to any one of claims 1 to 5, further comprising a system for stopping the pump in a case, preventing idling of the pump, and protecting the pump. 7. The hot water supply system further detects the temperature in the open-air warming hot water storage tank, and when the temperature becomes abnormally high, stops heating from a heating source and takes water from the hot water storage tank. 2. The system according to claim 1, further comprising a system for stopping the pump and protecting the hot water tank, the pump, and the piping.
The hot water supply system according to any one of Items 1 to 6.