JP2524952Y2 - Electric water heater - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater used in a general house or the like.

[0002]

2. Description of the Related Art As an electric water heater used in a general house, water stored in a hot water storage tank is heated by an electric heater disposed in the tank, and the entire water in the hot water storage tank is heated by natural convection. The structure of boiling up is generally used. However, the electric water heater having a general structure has a disadvantage that the installation space is very large, and it is becoming difficult to install the water heater in a small space due to a rising land price. Therefore, recently, an electric water heater of a heating unit separation type, which aims to save space in an installation place by separating a hot water storage unit from a heating unit and disposing the hot water unit in a dead space such as under a floor. Proposed.

[0003]

[Problems to be Solved by the Invention] By the way, according to the electric heater of the above-mentioned separated heating unit type, the hot water storage unit (hot water storage tank) needs to be open to the atmosphere. There are the following problems. That is, according to the Water Law,
If a pump is used as a direct connection to the water pipe, there must be no fluctuations in the primary pressure, and in the case of a device (tank) that is open to the atmosphere, the cross connection between the tank and the water pipe and the end of the tank There is a provision that there must be no cross connection in the mixing valve, and these problems become a problem when the hot water tank is of the open-to-atmosphere type. Therefore, as a workaround, as shown in FIG.
It is considered to arrange the pressure cistern 110 on the water supply side of the hot water storage tank 101. However, according to such measures, the cost is increased by the pressure cistern 110, and it is necessary to secure the installation space. New problems arise.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a structure in which a heating unit and a hot water storage unit are separated, and the hot water storage unit is open to the atmosphere. Another object of the present invention is to provide an electric water heater that does not require a pressure cistern.

[0005]

[Problem to be Solved by the Invention] A configuration for achieving the above object will be described with reference to FIG. 1 corresponding to an embodiment. The present invention provides a hot water storage tank 1 that is open to the atmosphere and a hot water storage tank 1. A hot water supply pipe 3 having one end communicating with a bottom portion in the hot water storage tank 1 and a mixing valve 5 connected to the other end, and a hot water supply connected to the hot water supply pipe 3 One end is connected to the pump 3a and the water pipe, the other end is branched in two directions, one branch pipe 61 is connected to the hot water storage tank 1 via a water supply valve, and the other branch pipe 62 is connected to the mixing valve 5. Water supply pipe 6 connected to the other water inlet of the vehicle, and a faucet switch 8 for indicating the presence or absence of hot water
And a control device 7. The control device 7 controls the hot water supply pump 3a only when the faucet switch 8 is ON.
And the hot water supply pipe 3 of the mixing valve 5
This is characterized in that control is performed such that the side flow path is opened and the water supply valve 61a is closed when the hot water supply pump 3a is driven.

[0006]

When supplying hot water by driving the hot water supply pump 3a, the water supply valve 61a is always set to be closed, so that the edge between the hot water storage tank 1 and the water pipe is cut off. Therefore, the hot water supply pump 3a is not directly connected to the water supply pipe, and the flow path of the mixing valve 5 on the hot water supply pipe 3 side is opened only when the hot water supply pump 3a is driven. There is no cross connection.

[0007]

FIG. 1 is a piping diagram showing the configuration of an embodiment of the present invention. Hot water storage tank 1 and air opening 1a in the upper wall
Is an open-to-atmosphere tank provided with. A hot water supply pipe 3 is connected to the bottom of the hot water storage tank 1. The other end of the hot water supply pipe 3 is connected to a mixing valve 5, and a hot water supply pump 3a is connected in the middle of the pipe. In addition, the air opening 1a is subjected to insect and dustproof treatment.

The heating section 2 is constituted by a heating tank, an electric heater, a circulation pump (both not shown) and the like. A circulation pipe 4 is connected between the heating unit 2 and the hot water storage tank 1, and the water stored in the hot water storage tank 1 can be heated and circulated by driving the heating unit 2. On the other hand, the water supply pipe 6 has one end connected to a water pipe (not shown) and the other end branched in two directions. One of the branch pipes 61 communicates with an upper position in the hot water storage tank 1 via a water supply valve 61a, and the other branch pipe 62 is connected to another water inlet of the mixing valve 5.

The control unit 7 controls the driving and stopping of the heating unit 2 and the hot water supply pump 3a, the opening and closing of the water supply valve 61a, and the adjustment of the opening of the mixing valve 5 respectively. Further, a faucet switch 8 for instructing the presence or absence of hot water supply is connected to the control device 7. Next, the operation of the embodiment of the present invention together with the operation of the control device 7 will be described.

First, in the heating operation in the time zone of the midnight electricity bill (11:00 pm to 7:00 am), the controller 7
When the water level in the hot water tank 1 is equal to or less than the set capacity, the water supply valve 61a is opened to fill the hot water tank 1 with water, and then the heating unit 2 is driven to boil the water stored in the hot water tank 1.
Thereafter, until the next boiling operation is performed, the water supply valve 6 is stopped.
1a is kept closed. In addition, the water supply to the hot water storage tank 1 is configured, for example, by providing a water level sensor in the hot water storage tank 1 and based on the detected value.

When the faucet switch 8 is turned on after the above-described boiling operation is completed, the hot water supply pump 3a is driven and the mixing valve 5 is operated to open the flow path of the hot water supply pipe 3. Thereby, the mixing valve 5
From the hot water, hot water mixed with water and hot water from the hot water storage tank 1 at an appropriate temperature flows out. However, when the mixing valve 5 is not driving the hot water supply pump 3a, the opening degree of the flow path on the hot water supply pipe 3 side is always kept closed.

[0012]

[Effects of the Invention] As described above, according to the present invention, a water supply valve is provided in a water supply pipe to a hot water storage tank of an open-to-atmosphere type having a separate heating unit, and the water supply valve is always closed when the hot water supply pump is driven. Since the hot water storage tank and the water pipe are completely separated from each other, there is no direct connection between the hot water supply pump and the water pipe, and there is no cross connection at the mixing valve at the end of the hot water supply pipe. Therefore, even if the hot water tank is open to the atmosphere, it is not necessary to provide a pressure cistern on the water supply side of the hot water tank.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing an example of a countermeasure such as cross connection when a hot water tank is opened to the atmosphere in an electric water heater of a separated heating part type.

[Explanation of symbols]

 1 hot water storage tank 2 heating unit 3 hot water supply pipe 3a hot water supply pump 4 circulating pipe 5 mixing valve 6 water supply pipe 61 · · · · · Branch pipe 61a · · · Water supply valve 7 · · · Controller 8 · · · faucet switch

Claims (1)

(57) [Scope of request for utility model registration] 1. An open-air hot water storage tank, a heating section for heating water stored in the hot water storage tank, one end communicating with a bottom position in the hot water storage tank, and a mixing valve connected to the other end. One end is connected to a hot water supply pipe, a hot water supply pump connected to the hot water supply pipe, and a water pipe, and the other end is branched in two directions, and one of the branch pipes is connected to the hot water storage tank via a water supply valve. A water supply pipe having the other branch pipe connected to the other water inlet of the mixing valve, a faucet switch for instructing the presence or absence of hot water supply, and a control device, and the control device includes the faucet switch. Only when the state is ON, the hot water supply pump is driven, the flow path of the mixing valve on the hot water supply pipe side is opened, and the control of setting the water supply valve to closed when the hot water supply pump is driven is performed. Is configured as Electric water heater that.