JPH01234749A - Additional heating method and its device of hot water of bathtub by using electric hot water heater - Google Patents

Abstract

PURPOSE:To allow additional heating of a bathtub water without impairing the characteristics of electric hot water heater with the advantage of using the power of specially reduced rate in midnight by exchanging the quantity of heat of an intermediate layer of hot water stored in a hot water storage tank of an electric hot water heater for the hot water filled in a bathtub by a heat exchanger. CONSTITUTION:A heat exchanger 2 incorporated in a hot water storage tank T of an electric hot water heater A and a circulating pipe line 3 for circulating hot water of a bathtub B in the heat exchanger 2 are prepared. The heat exchanger 2 is formed of coiling a pipe 20 and positioned at the upper part of the hot water of an intermediate layer part W2 at a position descended a little from an upper layer part W1. The circulating pipe line 3 is connected to the discharge opening 40 and the return opening 41 of a bathtub 2 and both free ends of the pipe 20 of the heat exchanger 2, a circulating passage is formed and a pump P is connected to suck the hot water from the side of the heat exchanger 2 to send it to the return opening 41 of the bathtub B. When the starting switch of the pump P is turned ON an additional heating device composed of the heat exchanger 2, the bathtub B and the circulating pipe 3 is actuated and additional heating in the hot water of the bathtub can be performed without impairing the characteristics of the electric hot water heater with the advantage of using the power of specially reduced rate in midnight.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in a method and a reheating device for reheating hot water in a bathtub using an electric water heater, which uses low-source electric power at night.

BACKGROUND ART Systems known as central heating, in which hot water is supplied from a hot water supply facility to a bathtub in a bathroom, have been in existence for a long time. In this method, hot water is supplied to the bathtub using a drop-in method, in which hot water is boiled in a large storage type boiler, guided into the bathroom via hot water supply piping, and then released into the bathtub as hot water at a predetermined temperature via a mixing valve. When the temperature of the hot water inside the tank drops due to cooling, the hot water is poured out to raise the temperature.

By the way, in order to avoid the inconvenience of increasing the temperature of hot water by pouring hot water into the bathtub from a hot water supply facility, a means for reheating has recently been developed.

This means that the boiler for reheating the water is equipped with a separate burner that uses gas or oil for reheating, and a heat exchanger that circulates the hot water in the bathtub is installed, and the burner for reheating is activated. Either raise the temperature of the hot water in the bathtub, or install a separate boiler that circulates the hot water in the bathtub and reheats it, and use that boiler with a gas or oil-fired burner. These devices are designed to be operated by actuation, and all of them use gas burners or oil burners, and there are no methods of supplying hot water to bathtubs using electric water heaters that allow reheating. .

This is because the electric water heater is built in the form of a thermal storage type port that uses electricity from the late-night special rate from 1:00 a.m. to 4:00 a.m., and is used in daily life outside of the late-night special rate. During these hours, the switch may not be turned on, or the electricity usage fee will be charged at the normal rate, making the use of electricity for additional heating more expensive, and the electric heater being turned on. If you try to reheat the water by exchanging heat between the hot water in the tank of the electric water heater and the hot water in the bathtub, the heat stored in the hot water in the tank will be consumed, causing the water temperature to drop.
This is because electric water heaters, which are regenerative water heaters, will no longer function as water heaters.

The present invention provides a method for reheating hot water in a bathtub heated using an electric water heater, which has been considered difficult in the past, without destroying the characteristics of the electric water heater that uses electricity at special late-night rates. Moreover, it is an object of the present invention to provide a new means for reheating hot water in a bathtub without losing its function as a regenerative water heater.

Therefore, the present invention has been completed based on the knowledge obtained through various studies and experiments for the above-mentioned purpose. That is, the electric water heater A, as shown in FIG.
A water supply port 10 is provided at the bottom to connect the water supply pipe leading to the water faucet, and a flaw removal port 1 is provided at the top to connect the hot water supply pipe.
1 is filled with water from the water supply port 10 into the hot water storage tank T, and the water is placed at the bottom of the inner cavity of the hot water storage tank T during the late-night special rate period. Electric heater H that only turns on (usually from 1 a.m. to 4 a.m.)
As a result, when using 7μ, it is stored in the hot water storage tank T as high temperature hot water without convection.
When the hot water faucet C connected to the hot water supply pipe is opened, cold water flows into the bottom of the hot water storage tank T from the lower water supply port 10 connected to the water supply pipe A, corresponding to the amount of cold water that has flowed in. The amount of hot water that flows out from the hot water faucet C is pushed out from the flaw outlet 11 at the top, and the level of cold water that flows into the bottom of the hot water storage tank T each time hot water is used. The hot water gradually rises while pushing up the layer of hot water, and hot water can be taken out until the cold water level reaches the wound outlet 11, but when the hot water is used up, the hot water storage tank T
If the water inside is completely cold, you will have to wait until the late-night special rate period to use the hot water.

Therefore, this electric water heater A is equipped with a heat exchanger 2 in the storage 1gI tank T as shown in FIG. By arranging the hot water in the bathtub B and communicating it with the bathtub B via a circulation pipe 3 equipped with a circulation pump P, the hot water in the bathtub B is circulated to the heat exchanger 2 by the operation of the pump P. If heating is enabled, when the hot water in the bathtub B is circulated through the heat exchanger 2, convection will occur in the hot water stored in the hot water tank T, and the entire hot water in the hot water tank T will be heated. This causes the temperature to drop and it loses its function as a water heater, and this is a constraint that prevents electric water heater A from being equipped with a means to reheat the hot water in bathtub B. It is something that

By the way, although electric water heater A has such limitations, it focuses on the fact that boiled hot water is stored in the hot water storage tank T without convection, and When installing the heat exchanger 2 that circulates hot water and exchanges heat for reheating into the hot water storage tank T, the heat exchanger 2 is installed between the upper and lower parts of the hot water storage tank T as shown in FIG. The heat exchanger 2 is installed locally at a mid-height position, approximately one-third from the top, and the convection generated by contact with the heat exchanger 2 is applied to the upper layer of the heat exchanger, excluding the hot water in the upper layer. When the hot water in the hot water storage tank T is set to be carried out only in the lower middle part and below, the hot water in the hot water storage tank T remains boiled to a high temperature above the part where it comes into contact with the heat exchanger 2, The temperature of the hot water below the body part begins to drop through heat exchange with the hot water in bathtub B, and the high-temperature hot water from electric hot water @A is stored in its hot water storage tank T. The hot water in the bathtub B is transferred to the hot water storage tank T while
The results showed that the temperature could be raised through heat exchange with the hot water inside.

Based on this, in the present invention, as a means to achieve the above-mentioned object, the hot water in the middle part of the hot water stored in the hot water storage tank of the electric water heater, which is slightly below the upper part, is We proposed a method for reheating hot water in a bathtub using an electric water heater that exchanges heat with the hot water filled in the bathtub using a heat exchanger. A heat exchanger is installed in the hot water storage tank of an electric water heater, which has a water supply inlet, a layered outlet at the top, and an electric heater installed at the bottom of the inner cavity. An electric water heater installed in the bathtub that is arranged so as to be in contact with the hot water in the middle layer slightly lower, and the heat exchanger and the bathtub are connected via a circulation pipe equipped with a pump. This suggests a device for reheating hot water.

Next, embodiments will be described in detail with reference to the drawings. Note that the same reference numerals in the drawings as in the previous means are used for components having the same effect.

FIG. 3 is a partially cutaway side view of a first embodiment of a device for reheating hot water in a bathtub using an electric water heater according to the present invention, in which T is a hot water storage tank of electric water heater A; 2 is a heat exchanger built into the hot water storage tank T, B is a bathtub, and 3 is a circulation pipe for circulating hot water in the bathtub B to the heat exchanger 2.

The hot water storage tank T is provided with a water supply port 10 for connecting a water supply pipe a that communicates with a water faucet at the lower part, a hot water outlet 11 for connecting a hot water supply pipe that communicates with a hot water faucet C at the upper part, and a This is the hot water storage tank of an ordinary electric water heater A that has an electric heater H built into it. ing.

The heat exchanger 2 is a conventional one formed by winding a pipe 20 into a coil, and the length in the axial direction of the coil portion of the pipe wound around the coil is equal to the vertical height of the inner cavity of the hot water storage tank T. The hot water in the hot water storage tank T is formed to be about 1/3 to 1/4 of the original size, and the hot water in the hot water storage tank T is divided into an upper part W1, a middle part Wz, and a lower part W3. It is arranged so that it is located above the hot water in the middle part W2, which is slightly lower than the upper part wl when it is divided into three parts, and the inner free end of the pipe 20 is connected to the peripheral wall of the hot water storage tank T, so that it is watertight. It is installed in the hot water storage tank T by penetrating it and assembling it. The location where this heat exchange rA2 is installed is to ensure that high temperature hot water is stored in the upper part of the hot water storage tank T, and is limited to the one-third height position. Instead, it may be provided locally at a quarter height position or a half height position, respectively.

Bathtub B is a normal bathtub installed in the bathroom of a building.
The peripheral wall thereof has a discharge port 4o for sending the hot water in the bathtub B to the heat exchanger 2, and a return port 4o for returning the hot water that has passed through the heat exchanger 2 into the bathtub B. A port 41 is provided.

The circulation pipe line 3 is connected to the discharge port 4o and the return port 4 of the bathtub B.
1 and the inner free end of the pipe 2o of the heat exchanger 2 described above are connected to form a circulation path together with the bathtub B and the heat exchanger 2. Take a bath by sucking hot water! A pump P is connected so as to send the water to the return port 41 of B.

The control circuit of the motor that drives the pump P is provided with a start switch that drives the motor to operate the pump P. By turning on this start switch, the heat exchanger 2 and the bathtub The reheating device constituted by B and the circulation pipe 3 that connects them operates in the following manner.

Regarding electric water heater A, during times of daily life that are outside of the special rate contracted with the electric power company,
The hot water stored in the hot water tank T of the electric water heater A is not used, and therefore, the hot water tank T is filled with hot water heated to a temperature of approximately 95°C. In this state, assume that the hot water faucet C is opened and the hot water is poured into the bathtub B to a predetermined water level while mixing with water so that the hot water has a temperature suitable for bathing. Assume that the amount of hot water used at this time was about one-third of the amount of hot water in the hot water storage tank T.

Then, inside the hot water storage tank T, there are an upper part W1 and a middle part W2.
- If the water is divided into three layers, the lower layer W3, the lower layer W3 will be cold water, and the middle layer W2 and the upper layer W1 will be hot water.

Next, suppose that in this state, the temperature of the hot water in bathtub B drops due to cooling and becomes lukewarm.

At this time, if the start switch is turned on and the pump P is activated to operate the reheating device, the hot water in the bathtub B is transferred through the circulation pipe 3 to the heat exchanger 2 installed in the hot water storage tank T.
The hot water circulates through the water, exchanges heat with the hot water in the hot water storage tank T, and heats up, allowing reheating to take place.

At this time, convection occurs in the hot water in the hot water storage tank T as the temperature of the hot water in the area in contact with the heat exchanger 2 decreases, but the convection does not reach the upper part wl, and The middle layer W has almost no effect on the lower layer W3, which is a cold water layer.
This will only be done in 2.

Therefore, the hot water in the upper layer W1 remains at a high temperature, and the temperature of the hot water in the middle layer W2 decreases by the amount of heat exchanged with the hot water in the bathtub B via the heat exchanger 2. , hot water boiled to a high temperature will be taken out from the hot water faucet C.

Next, FIG. 4 is a longitudinal side view of another embodiment of the apparatus.

In this embodiment, the open port 50 at the inner end of the hot water storage tank T of the embodiment device shown in FIG. The only difference from the apparatus of the embodiment shown in FIG. 3 described above is that a second flaw removal port 5 communicating with the portion W2 is provided, and the rest of the structure is the same. Components having the same effect are designated by the same reference numerals, and detailed description thereof will be omitted.

Therefore, in this embodiment, the second hot water supply pipe b' is connected to the second wound removal port 5, and a shower faucet 51 used in the bathroom where the bathtub B is installed. It is connected to an upstream hot water faucet 52.

This embodiment device operates in the same manner as the embodiment device shown in FIG. 3, and also allows hot water at a temperature close to the appropriate temperature to be taken out from the shower faucet 51 and the hot water faucet 52. That is, the hot water taken out from the second flaw removal port 5 has a temperature close to that of the hot water in the bathtub B through heat exchange with the hot water in the bathtub B by the heat exchanger 2 when the bathtub B is reheated. Since it is descending, the hot water in the middle layer W2 around the heat exchanger 2 taken out from the second flaw removal port 5 is transferred to the first flaw removal port 11.
The upper part W1 in the hot water storage tank T taken out through the hot water supply piping is also at a lower temperature than the hot water taken out, so that it can be used safely and appropriately for showers and hot water.

Next, FIG. 5 shows a further different embodiment.

In this embodiment, the second hot water supply pipe b° connected to the second flaw extraction port 5 of the embodiment device shown in FIG. The bathtub B can be filled with hot water automatically by being connected to the circulation pipe 3 that connects the bathtub B via a communication path 6 that includes an automatic mixing faucet 60 and a system tank 61. This is an example, and other than this point, the rest of the configuration is the same as the example shown in FIG. do.

Therefore, in this embodiment, the check valve 62 → the automatic mixing faucet 6
0 hot water inlet → Mixed water outlet of the mixing faucet 60 → Solenoid valve 63
→ Connect the communication path 6 that connects the system tank (or hopper) 61 → the solenoid valve 64 in this order, and connect the communication path 6 to the bathtub B.
and the heat exchanger 2 in the hot water storage tank T.
is connected to the suction side of the pump P connected thereto, and a pipe 65 communicating with the water faucet is connected to the water inlet of the mixing faucet 60 via a check valve 66, and further, A pressure sensor S is connected to the bathtub B to detect the water level of hot water poured into the bathtub B, and the electric signal of the water level detected by the pressure sensor S is used to control the electromagnetic valve 6 described above.
3-64 are interlocked to perform on/off control.

As a result, when the switch for starting the reheating device provided in the control circuit of the pump P connected to the circulation pipe 3 is turned on, at that time, the bath 46B is empty or the water level of the hot water is low. When the pressure sensor S detects that the water level is lower than the predetermined water level set thereto and sends the electric signal to the control circuit of the solenoid valves 63 and 64, the solenoid valves 63 and 64 is operated to open the valve, and the hot water in the middle part W2 in the hot water storage tank T flows from the second flaw removal port 5 through the communication path 6 into the circulation pipe 3 on the suction side of the pump P, and this hot water is sent into the bathtub B by the operation of the pump P, and as a result, the water level in the bathtub B rises and reaches a predetermined water level.The pressure sensor S detects this and sends the electric signal to the solenoid valve 63 and the fist 64. Send to control circuit, solenoid valve 63.6
After the valve 4 is closed and hot water supply is stopped, the hot water in the bathtub B is circulated to the heat exchanger 2 by the operation of the pump P, and the reheating operation is started.

This embodiment operates in the same manner as the embodiment shown in FIG. 4, and, as described above, automatically returns the amount of hot water in the bathtub B to a predetermined water level when reheating.

Next, FIG. 6 shows a further different embodiment.

This embodiment is a modification of the basic reheating device according to the present invention shown in FIG.

In other words, the heat exchanger performs reheating by exchanging the heat of the hot water in the middle part W2 of the hot water in the hot water storage tank T with the hot water in the bathtub B using a heat exchanger, but the heat exchanger This is an example of a configuration in which heat exchange is performed indirectly.

In this embodiment, a circulation pipe 70 is connected to the hot water storage tank T to take out the hot water in the middle layer W2 of the hot water inside the tank and return it to the middle layer W2 again. 71 and a pump P' are connected, and this heat exchanger 71 is disposed outside the hot water storage tank T and placed inside a tank 73 filled with a heat medium 72. Inside the tank 73, a circulation pipe is connected to the bathtub B. The heat exchanger 2 connected and communicated via the passage 3 is housed in parallel with the aforementioned heat exchanger 71, and thereby,
Heat exchange between the hot water in the hot water storage tank T and the hot water in the bath 46B is performed indirectly.

The rest of the structure is the same as that of the embodiment shown in FIG. 3, and the same reference numerals are given to constituent members having the same effect, and detailed explanation thereof will be omitted.

This embodiment is similar to the third
It operates in the same way as the embodiment shown in the figure.

As explained above, the means of the present invention utilizes the amount of heat stored in the hot water storage tank of an electric water heater in the middle layer, which is slightly below the upper layer, to be pumped into the bathtub using a heat exchanger. By exchanging heat with the hot water, the hot water in bath 46B is reheated, so it does not lose the characteristics of an electric water heater that uses electricity at special late-night rates, and still functions as a regenerative water heater. To make it possible to reheat hot water in a bathtub without losing water.

In addition, the heat exchanger 2 is installed in a hot water storage tank T of an electric water heater A, which has a water supply port 10 at the bottom, a field outlet 11 at the top, and an electric heater H at the bottom of the inner cavity. The heat exchanger 2 and the bathtub B are arranged so as to be in contact with the middle layer of hot water slightly below the upper layer of the hot water in the tank T.
By connecting these through a circulation pipe 3 equipped with a pump P and configuring a device for reheating hot water in a bathtub using an electric water heater, the characteristics of the electric water heater can be maintained without sacrificing the properties of the heat storage type. A reheating device that allows reheating without losing the function of the hot water boiler,
It can be obtained with a simple structure.

In addition, by separately installing a second field outlet 5 in the η hot water tank T that communicates with the middle layer near the upper layer of the hot water stored inside it, it is possible to Hot water storage tank T whose temperature has dropped due to heat exchange due to reheating of hot water in B
The hot water in the middle part W2 of the interior can be effectively used for showers and hot springs.

In addition, by connecting the second field outlet 5 to the circulation pipe 3 via the communication path 6 equipped with an automatic mixing faucet 60 and a system tank 61, when reheating lμ of the bath 4eB, Using the circulation pipe 3 for reheating, the hot water storage tank T
Hot water from the middle part W2 inside the bathtub B can be additionally supplied to the bathtub B.

In addition, a hot water storage tank T of an electric water heater A, which has a water supply port 10 at the bottom, a water outlet 11 at the top, and an electric heater H at the bottom of the inner cavity, is provided with a middle layer of hot water inside the tank T. A circulation pipe 70 is connected to take out the hot water from the bathtub B and return it to the middle part of the hot water storage tank T through the heat exchanger 71, and the heat exchanger 71 and the bathtub B,! : A heat exchanger 2 connected via a circulation pipe 3 is installed in parallel in a tank 73 that is provided separately from a hot water storage tank T and stores a heat medium 72 inside, and the hot water in a bathtub using an electric water heater is heated. By configuring the reheating device, repair and inspection of the heat exchanger for reheating can be easily performed outside the hot water storage tank and bathtub, and maintenance thereof is facilitated.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of the conventional means, FIG. 3 is a vertical cross-sectional side view of an embodiment of the device of the present invention, FIG. 4 is a vertical cross-sectional side view of another embodiment of the device same as above, and FIG. 5 is the same as above. Fig. 6 is a longitudinal side view of still another embodiment of the same device. Explanation of drawing symbols

Claims (5)

[Claims] (1) An electric water heater that uses a heat exchanger to exchange heat from the middle layer of hot water stored in the hot water storage tank of the electric water heater, which is slightly below the upper layer, with the hot water filled in the bathtub. How to reheat hot water in a bathtub using a water heater. (2) A water supply port 10 is provided at the bottom and a hot water outlet 11 is provided at the top.
A heat exchanger 2 is installed in a hot water storage tank T of an electric water heater A, which is equipped with an electric heater H at the bottom of the inner cavity, and is placed in a middle layer slightly below the upper layer of the hot water in the hot water storage tank T. Hot water in a bathtub using an electric water heater, which is arranged so as to be in contact with the hot water in the bathtub, and the heat exchanger 2 and the bathtub B are connected via a circulation pipe 3 equipped with a pump P. reheating device. (3) The hot water storage tank T is provided with a second hot water outlet 5 which communicates with the middle layer near the upper layer of the hot water stored inside the tank T. A device that reheats hot water in a bathtub using an electric water heater. (4) In a bathtub using the electric water heater according to claim 2, the second hot water outlet 5 is connected to the circulation pipe 3 via the communication path 6 equipped with an automatic mixing faucet 60 and a system tank 61. Hot water reheating device. (5), with a water supply port 10 at the bottom and a hot water outlet 11 at the top
The hot water in the middle layer of the hot water inside the electric water heater A is taken out from the hot water tank T of the electric water heater A, which is equipped with an electric heater H at the bottom of the inner cavity, and is transferred to the hot water storage tank T through a heat exchanger 71.
A heat exchanger 71 for this and a heat exchanger 2 connected to the bathtub B via the circulation pipe 3 are installed separately from the hot water storage tank T, and a heat medium is installed inside the tank. 72
A device for reheating hot water in a bathtub using an electric water heater installed in parallel in a tank 73 that stores water.