JPH0579697A - Electric warm water supplying apparatus - Google Patents

Abstract

PURPOSE:To prevent lack of hot water by driving an electric heater when a water temperature in a heating tank is a set temperature or lower, driving a circulation pump when a water temperature in a hot water storage tank is a set temperature or lower, and stopping the circulation pump when supplying water quantity obtained from a detected flow rate reaches the capacity of the heating tank. CONSTITUTION:A controller 3 confirms full of water in a heating tank 22 by a water level sensor LS in a heating mode when the output of a temperature sensor TH2 of the tank 22 indicates a set temperature or lower, and drives an electric heater 23 to heat the water to a bathing temperature. When the output of a temperature sensor TH1 of a hot water storage tank side indicates a bathing temperature or lower, hot water of the tank 22 is supplied to the storage tank 12 by a circulation pump 21. It calculates a supplying water quantity to the tank 12 based on the detected value of a flow rate sensor FS, and stops the pump 21 when it reaches the capacity of the tank 22. Thus, low temperature hot water is replaced to the tank 22, and heated hot water is replaced to the tank 12.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric water heater.

[0002]

2. Description of the Related Art An electric water heater is conventionally provided with a hot water storage tank having a water supply port at the bottom and a hot water outlet at the top, and a heater (electric heater) attached to the bottom of the tank. In general, the water stored in the tank is heated by a heater provided at the bottom, and the convection of the water caused by the heating raises the entire water temperature in the hot water storage tank to the boiling temperature. And the above-mentioned boiling operation is usually configured to be performed in the time zone of the midnight electricity charge (11:00 pm to 7:00 am).

[0003]

By the way, according to the conventional electric water heater, the hot water storage tank and the heater have an integral structure, and the overall shape and size of the electric water heater is inevitably large. For this reason, there is a problem that the degree of freedom of installation conditions is narrow, a large amount of exclusive space is required, and in some cases outdoor specifications are required.

When hot water is supplied in excess of the hot water storage capacity of the hot water storage tank in an emergency or the like, so-called hot water shortage may occur in which only low temperature water is discharged from the hot water supply port.
When such hot water runs out, conventionally, it is necessary to heat the entire water in a large-capacity hot water storage tank (for example, 500 liters) to the boiling temperature, which requires a long time for heating. There was a problem that hot water could not be supplied over time.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to have a structure in which a hot water storage tank and a heater are separated, and moreover, when hot water runs out. Is to provide an electric water heater having a structure capable of supplying hot water in a short time.

[0006]

Means for Solving the Problems A structure for achieving the above object will be described with reference to FIG. 1 corresponding to an embodiment. The present invention provides hot water storage tanks 11 and 12, and a bottom position in the tank. Water supply pipe 13 that communicates with the hot water supply pipe 14 that communicates with the upper position of the water supply pipe 13 and the suction port
A circulation pump 21 communicating with a bottom position in the inside, a heating tank 22 having an inside communicating with a discharge port of the pump 21, and an electric heater 23 having a heating element arranged inside the tank 22.
And detecting the water temperature at the bottom of the hot water storage tank 11
The temperature sensor TH1, the second temperature sensor TH2 for detecting the water temperature in the heating tank 22, the flow rate sensor FS for detecting the flow rate of the water supplied to the heating tank 22 by the circulation pump 21, and the control means 3. I have it. The control means 3 drives the electric heater 23 when the temperature detected by the second temperature sensor TH2 is equal to or lower than the set temperature, and when the water temperature in the heating tank 22 reaches the set value, the electric heater 23 of the electric heater 23 is driven. Driving is stopped, and at this point, the first temperature sensor TH1
When the temperature detected by is equal to or lower than the set temperature, the circulating pump 21 is driven and the amount of supplied water is calculated from the detected value of the flow rate sensor FS.
It is characterized by being configured so that the driving of the circulation pump 21 is stopped when the capacity of 2 is reached.

[0007]

[Operation] First, the control means 3 includes the second temperature sensor TH2.
The electric heater 23 is driven and controlled based on the above, to boil the water in the heating tank 22. When the temperature detected by the first temperature sensor TH1 is equal to or lower than the boiling temperature at the time when the boiling operation is completed, the circulation pump 21 is driven, and the supply amount of the pump is equal to the capacity of the heating tank 22. When this happens, the drive of the circulation pump 21 is stopped. By this operation, the heating tank 22 is filled with the low temperature water from the hot water storage tank 11, and at the same time, the hot water heated in the heating tank 22 is supplied to the upper portion of the hot water storage tank 12.

By repeating the above operation, the hot water storage tank 12 (11) is sequentially supplied with hot water of the capacity of the heating tank 22, and the water temperature at the bottom of the hot water storage tank 11 is set to the set temperature. Reaching the first temperature sensor
The boiling operation is completed when it is detected by TH1. Here, the control means 3 controls the drive of the electric heater 23 based on the output of the second temperature sensor TH2 after the midnight power supply start time (11:00 pm) to heat the water temperature in the heating tank 22. When the hot water is run out, the circulating pump 21 is driven once to keep the heating tank 22 above the hot water tank 12 when the hot water runs out.
The amount of hot water equivalent to the capacity of can be secured.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of the present invention, in which a piping system diagram and a block diagram of a control system are shown together. The hot water storage tank 1 includes first and second hot water storage tanks 11 and 12. The two tanks 11 and 12 are connected to each other by a connecting pipe 1a.
The upper part in the first tank 11 and the bottom part in the second tank 12 communicate with each other. The first and second hot water storage tanks 11 and 12 are
The standing tanks have almost the same shape and each has a capacity of 250 liters.

Further, the first hot water storage tank 11 is connected with a water supply pipe 13 which communicates with a bottom position inside thereof. A water tap 4, a pressure reducing valve 5 for reducing the primary pressure of the water supply, and a flow switch 6 are sequentially connected to the water supply pipe 13. Further, a hot water supply pipe 14 communicating with an upper position inside the second hot water storage tank 12 is connected,
A hot water supply tap 7 is connected to the hot water supply pipe 14 at the end.

On the other hand, the heater 2 is composed of a closed type heating tank (capacity 50 liters) 22, an electric heater 23 in which a heating element is arranged, a circulation pump 21 and the like. The discharge port of the circulation pump 21 communicates with the bottom position in the heating tank 22 through the flow rate sensor FS and the check valve 24, and the suction port has a bottom end in the first hot water storage tank 11. The outgoing pipe 15 communicating with the position is connected. A return pipe 16 having an end communicating with an upper position in the second hot water storage tank 12 is connected to an upper portion of the heating tank 22, and when the circulation pump 21 is driven in these piping systems, the first Hot water storage tank 11 → heating tank 22 → second hot water storage tank 12 → first hot water storage tank 1
Water can be circulated in the order of 1. The valve 25 connected to the heating tank 22 is a safety valve for preventing the internal pressure of the heating tank 22 from exceeding a specified pressure.

The first hot water storage tank 11 is provided with a temperature sensor TH1 for detecting the water temperature at the bottom of the first hot water storage tank 11, and the second hot water storage tank 12 has 50 liters of hot water remaining from the upper portion thereof. There is a hot water detection sensor HS that can detect up to 150 liters per unit. Further heating tank 2
2 includes a temperature sensor TH2 that detects the internal water temperature and a high limit sensor HL that detects an excessive temperature rise of the internal water temperature.
A water level sensor LS for detecting whether or not the inside of the tank is filled with water is arranged at an appropriate position.

The output signals of these sensors TH1, TH2, HS, HL, LS and the flow switch 6 connected to the water supply pipe are input to the controller 3. The control device 3 is configured to perform drive control of the electric heater 23 and the circulation pump 21, which will be described later, based on these input signals. Further, the control device 3 controls the temperature sensor TH on the hot water storage tank side.
Based on the detection value of 1, the peak shift at the start of the boiling operation in the time zone of the late-night electricity charge is calculated, and the amount of remaining hot water is displayed on the display (not shown) based on the output of the remaining hot water detection sensor HS. ) Etc. are also configured to perform the operation of a general electric water heater.

Next, the operation of the controller 3 and the operation of the embodiment of the present invention will be described. First, when the output of the temperature sensor TH2 of the heating tank 22 is a signal indicating a set temperature (boiling temperature 85 ° C.) or less in the boiling mode, the control device 3 detects the heating tank 22 from the water level sensor LS.
Electric heater 2 after confirming that water is filled in
Drive only 3. Due to this heating, the water temperature of the heating tank 22 rises, and when the water temperature reaches the boiling temperature, the driving of the electric heater 23 is stopped.

At the time of such a boiling state,
When the output of the temperature sensor TH1 on the hot water storage tank side is a signal indicating the boiling temperature or less, the circulation pump 21 is driven. While driving the pump, the control device 3 calculates the amount of water supplied to the heating tank 22 based on the detection value of the flow rate sensor FS, and the calculated value becomes a value corresponding to the capacity of the heating tank 22, that is, 50 liters. At this point, the drive of the circulation pump 22 is stopped.

By this operation, the low temperature water from the first hot water storage tank 11 flows into the heating tank 22, the inside thereof is filled with the low temperature water, and the heating tank 22 is heated. 50 liters of hot water is supplied into the second hot water storage tank 12 and is stored in the upper part thereof. Then, the above operation is sequentially repeated until the value detected by the temperature sensor TH1 on the hot water storage tank side reaches the boiling temperature. By this repeated operation, the second hot water storage tank 12
50 liters of hot water are pushed into the inside one by one, first the second hot water storage tank 12 is filled with hot water, and then the first hot water storage tank 11 is filled with 50 liters of hot water from the second hot water storage tank 12. Are sequentially pushed in, and when the first hot water storage tank 12 is filled with hot water,
That is, the boiling operation is completed when the output of the temperature sensor TH1 becomes a signal indicating the boiling temperature.

When the hot water is used, the hot water at the upper part of the second hot water storage tank 12 flows out to the outside by opening the hot water tap 7, as in a general electric water heater. At the same time, however, new water is replenished in the first hot water storage tank 11 by the amount used for hot water supply. Here, the control device 3 controls the driving of the electric heater 23 to maintain the water temperature in the heating tank 22 at the boiling temperature after the midnight power energization start time (11:00 pm). The value detected by the residual hot water sensor HS is
When it becomes less than 50 liters, the circulation pump described above is driven only once. As a result, the second hot water storage tank 1
At least 50 liters of hot water can be secured in 2. Therefore, even if the hot water runs out, the waiting time for hot water supply can be short. However, the circulation pump is driven by the first hot water storage tank 11 by the flow switch 6 of the water supply pipe.
When it is detected that water is being supplied to the inside, it is stopped. Further, the control device 3 is a high limit sensor HL.
However, the drive of the electric heater 23 is immediately stopped when, for example, 95 ° C. is detected.

In the above embodiments of the present invention, the hot water storage tank 1 has a structure provided with two hot water storage tanks in order to make it thin, but the number of hot water storage tanks may be one. Alternatively, it may be an arbitrary plural number of three or more.

[0019]

As described above, according to the present invention, the external pipe system capable of circulating the water in the hot water storage tank from the bottom to the upper part thereof and the electric heater connected to the pipe system are provided, and the heating thereof is performed. By supplying hot water boiled in the heating tank of the vessel by pushing it into the upper part of the hot water storage tank in sequence,
Since the whole hot water storage tank is filled with boiling water, the hot water storage tank and the heater can be installed separately, increasing the degree of freedom of installation conditions and creating a private space indoors. It can be significantly reduced compared to the conventional one.

Further, the power supply start time at midnight (11 pm
After that, when hot water having a capacity larger than that of the hot water storage tank is used, if the water temperature in the heating tank is the boiling temperature, the hot water in this tank is immediately supplied to the hot water storage tank. Even if the water temperature in the heating tank is below the boiling temperature, it will be boiled and supplied into the hot water storage tank in a short time, so even if the hot water runs out, hot water equivalent to the capacity of the heating tank It is possible to supply hot water in a short time.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, showing a block diagram of a piping system and a control system together.

[Explanation of symbols]

 1 ... ・ Hot water storage tank 11 ・ ・ ・ ・ ・ ・ First hot water storage tank 12 ・ ・ ・ ・ Second hot water storage tank 1a ・ ・ ・ ・ ・ ・ Connection pipe 13 ・ ・ ・ ・ ・ ・ Water supply pipe 14 ・ ・ ・ ・ Hot water supply pipe 15 ・・ ・ ・ Outward piping 16 ・ ・ ・ Return piping 2 ・ ・ ・ Heating device 21 ・ ・ ・ ・ Circulation pump 22 ・ ・ ・ ・ Heating tank 23 ・ ・ ・ ・ ・ ・ Electric heater TH1 ・ ・ ・ ・ ・ ・ First temperature sensor TH2 ・ ・ ・ ・ Second temperature sensor FS ・ ・ ・ ・ Flow sensor 3 ・ ・ ・ ・ Control device

Claims (1)

[Claims] 1. A hot water storage tank, a water supply pipe communicating with a bottom position in the tank and a hot water supply pipe communicating with an upper position thereof, a circulation pump having a suction port communicating with a bottom position in the hot water storage tank, and the pump. Of the inside of the heating tank, an electric heater having a heating element inside the tank, a first temperature sensor for detecting the water temperature at the bottom of the hot water storage tank, and the inside of the heating tank. A second temperature sensor for detecting a water temperature, a flow rate sensor for detecting a flow rate of water supplied to the heating tank by the circulation pump, and a control unit are provided, and the control unit is the second temperature sensor. When the detected temperature is equal to or lower than the set temperature, the electric heater is driven, and when the water temperature in the heating tank reaches the set temperature, the driving of the electric heater is stopped, and When the temperature detected by the first temperature sensor is equal to or lower than the preset temperature, the circulating pump is driven and the amount of supplied water is calculated from the value detected by the flow rate sensor, and the calculated amount of water reaches the capacity of the heating tank. An electric water heater configured to stop driving of the circulation pump at the time of performing.