JPH07239153A - Underground embedment type hot water storage type electric water heater - Google Patents

Abstract

PURPOSE:To obtain an underground embedment type hot water storage type electric water heater enabling checkup and repair of a heater, an electrification control device, etc., without drawing up a hot water storage tank from an underground pit. CONSTITUTION:A heater insertion port 1c is formed in a hot water storage tank 1 so that it opens toward an opening of an underground pit P. A heater 2 is inserted into the hot water storage tank 1 from the heater insertion port 1c and disposed in an upper area inside the hot water storage tank l. A circulation passage 3 making an area above the heater 2 inside the hot water storage tank 1 communicate with a lower area inside the tank 1 is provided. A circulating pump 4 circulating water in the hot water storage tank 1 through the circulation passage 3 is disposed at a position in proximity to the opening of the underground pit P. Moreover, an electrification control device 7 executing a control of the heater 2 and the circulating pump 4 is disposed in the upper part of the hot water storage tank 1. A drain pipe L5 is connected to the circulation passage 3 through the intermediary of a three-way valve 5. The three-way valve 5 is provided at a position at which the water in the hot water storage tank 1 can be discharged outside through the drain pipe L5 by operating the circulating pump 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground underground hot water storage type electric water heater.

[0002]

2. Description of the Related Art As disclosed in Japanese Utility Model Laid-Open No. 57-179039, there is known an underground underground hot water storage type electric water heater in which a hot water storage tank equipped with a heater is arranged in an underground pit. If the hot water storage tank is placed in the underground pit, a space equivalent to the size of the hot water storage tank can be secured on the ground, and the hot water storage tank can be placed without damaging the appearance. In addition, the underground hot water storage type electric water heater has the advantages that the heat retention in the hot water storage tank is improved, and that no metal fittings or special construction for preventing the hot water storage tank from tipping over in an earthquake are required.

[0003]

In a general hot water storage type electric water heater, a heater is arranged in the lower portion of the hot water storage tank to boil hot water from the lower region of the hot water storage tank. By doing so, hot water convection occurs in the hot water storage tank, so that the hot water in the hot water storage tank can be naturally boiled. However, if the hot water storage tank is placed in the underground pit, there is a problem that the heater and the energization control device for the heater located at the bottom of the hot water storage tank cannot be inspected or replaced unless the tank is pulled up for inspection or repair. It was

An object of the present invention is to provide an underground buried hot water storage type electric water heater which can inspect and repair necessary electric parts such as a heater without pulling up the hot water storage tank from the underground pit.

Another object of the present invention is to provide an underground underground hot water storage type electric water heater capable of inspecting and repairing an energization control device for controlling energization of a heater or the like without opening a heavy opening closing cover. is there.

Another object of the present invention is to provide an underground underground hot water storage type electric water heater which can easily discharge water from the hot water storage tank.

It is still another object of the present invention to provide an underground underground hot water storage type electric water heater capable of preventing idle operation of the circulation pump.

[0008]

The present invention is directed to an underground buried hot water storage type electric water heater in which a hot water storage tank having a heater therein is disposed in an underground pit. In the present invention, the heater is inserted into the hot water storage tank from the heater insertion port provided in the hot water storage tank and is arranged in the upper area of the hot water storage tank, and the area above the heater in the hot water storage tank and the lower area of the hot water storage tank are arranged. A circulation path communicating with and is provided. Then, a circulation pump for circulating the water in the hot water storage tank through this circulation path is arranged at a position close to the opening of the underground pit,
The heater insertion port is formed in the hot water storage tank so as to open toward the opening of the underground pit, and the heater and the energization control device for the circulation pump are arranged above the hot water storage tank. Heater
It is preferably fixed to a lid member that closes the heater insertion port.

It is preferable that a handhole is formed at a position corresponding to the energization control device of the opening closing lid for closing the opening of the underground pit, and the handhole closing lid for closing the handhole is attached to the opening closing lid. In this way, it is possible to access the energization control device, which is frequently inspected and repaired, without opening the heavy opening block lid, and
The workability of repair is improved.

Further, it is preferable that a drain pipe is connected to the circulation path through a three-way valve, and the three-way valve is provided at a position where the water in the hot water storage tank can be discharged to the outside through the drain pipe by operating the circulation pump. By doing so, the water in the hot water storage tank can be discharged from the drain pipe by switching the three-way valve, so that when the heater is replaced or the hot water storage tank is replaced, the water in the hot water storage tank is discharged using a separate discharge pump. No need.

Further, a water flow sensor for detecting the presence or absence of water flow is arranged in the flow path from the lower region of the hot water storage tank of the circulation path to the circulation pump, and when the water in the hot water storage tank is discharged, the water flow sensor detects It is preferable to configure the energization control device so as to stop the circulation pump when it detects that there is no such.
In this way, the idle operation of the circulation pump can be prevented, and the burnout of the circulation pump can be prevented.

[0012]

When the heater insertion port provided in the hot water storage tank is provided so as to open toward the opening of the underground pit as in the present invention, the heater can be taken in and out of the hot water storage tank without pulling up the hot water storage tank from the underground pit. The heater can be easily inspected and repaired. If the circulation pump is located near the opening of the underground pit and the energization control device is located above the hot water storage tank, the circulation pump and the energization control device can be inspected and repaired without pulling up the hot water storage tank from the underground pit. There are advantages. Even if the heater is arranged in the upper region of the hot water storage tank, the water in the hot water storage tank is circulated through the circulation path, so that the hot water in the hot water storage tank can be entirely boiled.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a state in which an underground buried hot water storage type electric water heater according to an embodiment of the present invention is arranged in an underground pit. In the figure, 1 is a hot water storage tank, 2 is a heater, 3 is a circulation path, 4 is a circulation pump,
Reference numeral 5 is a three-way valve, 6 is a water flow sensor, 7 is an energization control device, 8 is a remote controller, 9 is a hot water supply passage, 10 is a heat insulating material made of glass wool or the like, and 11 is It is an opening closing lid. The hot water storage tank 1 has a heat insulating material 10 together with members attached to the hot water storage tank 1 such as the circulation path 3.
It is placed in the underground pit P in a state of being wrapped in. Of course, the heat insulating material 10 may be surrounded by an outer case. The underground pit P is constructed by burying a concrete cylindrical body with an open upper part in the ground. Of course, the underground pit P may be directly formed in the ground with concrete.

A water supply valve V is provided at the water supply port 1a of the hot water storage tank 1.
1, the water whose pressure is suppressed via the pressure reducing valve V2 and the check valve RV is supplied through the pipe line L1. And hot water storage tank 1
The hot water supply port 1b is connected to a pipe line L6 forming the hot water supply passage 9. In the upper part of the hot water storage tank 1, a cylindrical heater insertion opening 1c is formed so as to open toward the opening of the underground pit P. One end of the heater 2 arranged in the upper region of the hot water storage tank 1 is fixed to the lid member 2a that closes the opening end of the heater insertion opening 1c. Lid member 2a
The heater 2 fixed to has a portion extending toward the inside of the hot water storage tank 1 and a portion extending horizontally from this portion. The lid member 2a to which the heater 2 is attached is provided with an overheat prevention sensor 2b including a temperature sensor such as a thermistor. This overheat prevention sensor 2
b is provided to prevent boiling of the hot water when the hot water temperature exceeds a preset temperature. The output of the overheat prevention sensor 2b is sent to the energization control device 7, which will be described later, and the energization of the energization control device 7 is controlled.

A circulation passage outlet 1d for feeding hot water to the circulation passage 3 is provided in the lower portion of the wall of the hot water storage tank 1, and the circulation passage 3 is provided above the heater 2 on the wall of the hot water storage tank 1.
A circulation path inlet 1e for introducing hot water returning from the inside is provided. A first temperature sensor S1 for measuring the hot water temperature is attached at a position slightly above the heater 2 on the wall of the hot water storage tank 1, and the hot water temperature is measured at a position below the side wall of the hot water storage tank 1. The second temperature sensor S2 is attached. A thermistor or the like can be used as the first and second temperature sensors S1 and S2.

The circulation path 3 is composed of pipe lines L2 to L2 connected in series.
It is composed of L4. One end of the pipe L2 communicates with the circulation outlet 1d of the hot water storage tank 1, and the other end is connected to the pipe L3 via the circulation pump 4 at a position close to the opening of the underground pit P. Has been done. A water flow sensor 6 for detecting the presence / absence of a water flow flowing in the pipeline L2 is arranged in the pipeline L2. The circulation line 4 is the circulation pump 4
Is connected to one end of each of the pipeline L4 and the drain pipeline (drain pipe) L5 via the three-way valve 5. On both sides of the circulation pump 4, valves V3 and V4 which are closed when replacing or inspecting the pump are arranged.

The three-way valve 5 is driven by a drive source such as a motor so that the pipe line L3 can be switched so as to communicate with the pipe line L4 and the pipe line L5, respectively. It communicates with the pipeline L4. The other end of the pipe L4 communicates with the circulation passage inlet 1e of the hot water storage tank 1. The input terminal of the heater 2, the input terminal of the circulation pump 4, the driving means of the three-way valve 5, the output of the water flow sensor 6, and the outputs of the temperature sensors S1 and S2 are connected to the energization control device 7 arranged above the hot water storage tank 1. ing. This energization control device 7 responds to a command from the remote controller 8
It controls the energization of the heater 2 and the circulation pump 4.

The water supplied into the hot water storage tank 1 is boiled like the so-called constant temperature hot water supply type hot water storage type electric water heater.
First, the water supplied from the water supply port 1a is rapidly heated by the heater 2 arranged in the upper region of the hot water storage tank 1 to become hot water. Next, when the first temperature sensor S1 detects that the temperature of the heated hot water has reached 85 ° C., the circulation pump 4 is driven by the control of the energization control device 7, and the hot water flows in the direction indicated by the arrow h. The hot water in the hot water storage tank 1 is circulated. By this circulation, the hot water in the upper region of the hot water storage tank 1 and the water in the lower region or the low temperature hot water are mixed to lower the temperature of the hot water in the upper region. As a result, when the first temperature sensor S1 detects that the temperature of the hot water in the upper region of the hot water storage tank 1 has dropped to, for example, 75 ° C., the energization control device 7 stops the circulation pump 4. By repeatedly driving and stopping the circulation pump 4 as described above, the hot water in the entire hot water storage tank 1 can be boiled to a desired temperature. When the second temperature sensor S2 detects that the temperature of the hot water in the lower region of the hot water storage tank 1 has reached the boiling setting temperature, the energization control device 7 stops the energization of the heater 2 and the circulation pump 4 Also stops driving.

The hot water boiled as described above is sent to the hot water supply passage 9 only by water pressure. The hot water supply passage 9 is configured by connecting pipe lines L6 and L7 in series via a safety valve V5, and a curran 9a that forms a hot water supply port is connected to an end of the pipe line L7. Safety valve V5 is the hot water storage tank 1
This is a well-known valve that allows hot water to flow into the conduit L8 when the pressure of hot water flowing out of the hot water exceeds a certain value. Further, the pipeline L7 is connected to a pipeline L9 provided with a relief valve V6 above the safety valve V5. The relief valve V6 plays a role of flowing hot water into the pipe line L9 when the pressure of hot water sent from the hot water storage tank 1 exceeds a certain value, and a role of preventing negative pressure from being applied to the hot water storage tank 1. These pipelines L8 and L9 are arranged so as to flow the drainage to the common drainage pipeline L10 that causes the drainage channel M to drain the drainage together with the above-described drainage pipeline L5. In addition, a pipe line L11 for directly supplying water from the pipe line L1 to the karan 9a is also connected to the karan 9a.

The opening of the underground pit P in which the hot water storage tank 1 and the like are arranged is closed by an opening closing lid 11 formed by processing an iron plate. The opening closing lid 11 has a peripheral edge 11a as shown in FIG.
It is fixed to the underground pit P via the bolts 13 through 2. Further, in the opening closing lid 11, the pipe lines L5, L6, L1 are provided.
Holes 11b ... And hand holes 11c for penetrating 1 and L1 respectively are formed. At the penetrating portion where the conduit L5 penetrates the hole 11b, the conduit L5 penetrates the opening closing lid 11 via the rubber bush 14 (see FIG. 2). The conduits L6, L11, L1 also penetrate the opening closing lid 11 via the rubber bush 14 as in the conduit L5.

The handhole 11c is connected to the energization control device 7,
The opening closing lid 11 is formed at a position corresponding to the energization control device 7 so that the operator's hand can be put in, that is, accessible. A handhole closing lid 11d for closing the handhole 11c is attached to the opening closing lid 11. If the handhole closing lid 11d is opened, inspection and repair of the energization control device 7 can be easily performed.
For fixing the handhole closing lid 11d, bolting or screwing can be used.

Further, after the opening closing lid 11 is removed, the heat insulating material 1 on the heater insertion port 1c and the circulation pump 4 is removed.
If 1 is removed, the heater 2 and the circulation pump 4 can be easily accessed, and the heater 2 and the circulation pump 4 can be inspected and repaired without pulling up the hot water storage tank 1 from the underground pit P.

Although not shown, the pipe lines L5, L6,
L11 and L1 have a structure that can be separated by a joint above the opening blocking lid 11, and
The opening closing lid 11 can be easily removed by separating 5, L6, L11, and L1 at the joint portion. When the hot water storage tank 1 is pulled up from the underground pit P for replacement of the hot water storage tank 1 or the like, the hot water in the hot water storage tank 1 may be discharged as follows. First, close the water supply valve V1,
After opening the safety valve V5 and the relief valve V6, the three-way valve 5 is switched so that the pipeline L3 and the pipeline L5 communicate with each other. Next, the circulation pump 4 is driven to flow the hot water in the hot water storage tank 1 into the drain groove M from the outlet 1d. In this embodiment, a drain switch is provided in the remote controller 8 so that the three-way valve 5 can be automatically switched and the circulation pump 4 can be driven by a command from the energization control device 7 only by turning on the drain switch. . When the water flow sensor 6 detects that most of the hot water in the hot water storage tank 1 has been discharged and the water flow in the pipe line L3 has disappeared, the circulation pump 4 is stopped by a command from the energization control device 7.

[0024]

According to the present invention, since the heater insertion opening provided in the hot water storage tank is provided so as to open toward the opening of the underground pit, the hot water storage tank can be inserted into the hot water storage tank of the heater without pulling up from the underground pit. It is easy to put in and take out the heater, and it is easy to inspect and repair the heater. Also, place a circulation pump near the opening of the underground pit,
Since the energization control device is arranged above the hot water storage tank, there is an advantage that the circulation pump and the energization control device can be inspected and repaired without pulling up the hot water storage tank from the underground pit.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an underground buried hot water storage type electric water heater of the present embodiment.

FIG. 2 is a schematic partial cross-sectional view of an opening closing lid of the underground buried hot water storage type electric water heater of the present embodiment.

[Explanation of symbols]

 1 Hot water storage tank 1c Heater insertion port 2 Heater 3 Circulation path 4 Circulation pump 5 Three-way valve 6 Water flow sensor 7 Energization control device 8 Remote controller 9 Hot water supply path 11 Opening block lid 11c Handhole 11d Handhole block lid

Claims (4)

[Claims] 1. An underground buried hot water storage type electric water heater comprising a hot water storage tank having a heater disposed in an underground pit, wherein the heater is provided from a heater insertion port provided in the hot water storage tank. A circulation path is provided which is inserted into the tank and is arranged in an upper region in the hot water storage tank, and which connects a region above the heater in the hot water storage tank with a lower region in the hot water storage tank. And a circulation pump for circulating the water in the hot water storage tank through the circulation passage is arranged in a position close to the opening of the underground pit, and the heater insertion opening opens toward the opening of the underground pit. The underground hot water storage tank is formed in the hot water storage tank so that the heater and the energization control device for the circulation pump are arranged above the hot water storage tank. Electric water heater. 2. A handhole is formed at a position corresponding to the energization control device in an opening closing lid that closes the opening of the underground pit, and the handhole closing lid that closes the handhole is the opening. The underground underground hot water storage type electric water heater according to claim 1, which is attached to a part closing lid. 3. A drain pipe is connected to the circulation path via a three-way valve, and the three-way valve operates the circulation pump to discharge water in the hot water storage tank to the outside through the drain pipe. The underground underground hot water storage type electric water heater according to claim 1, wherein the electric water heater is underground. 4. A water flow sensor for detecting the presence / absence of a water flow is arranged in a flow path from a lower region of the hot water storage tank of the circulation path to the circulation pump, and the energization control device controls the water in the hot water storage tank. The underground buried hot water storage type electric water heater according to claim 3, wherein when the water flow sensor detects that there is no water flow, the circulation pump is stopped when the water is discharged.