JPH05133604A - Water heater - Google Patents

Abstract

PURPOSE:To provide a water heater in which the heating means does not operate even when a trouble is generated that an operation switch instructs the opening of a water solenoid valve in spite of the position of an operation knob at 'stop'. CONSTITUTION:This water heater is provided with an operation knob 6 that can freely set a 'stop' position range 61 in which an operation switch instructs the closing of a water stop solenoid valve and the contact points of a hot water and cold water switching switch are open, 'water' position range 62 in which the operation switch instructs the opening of the water stop solenoid valve and the contact points of the hot water and cold water switching switch are open, and 'hot water' position range 63 in which the operations switch instructs the opening of the water stop solenoid valve and the contact point of the hot water and cold water switching switch are closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a momentary hot water heater having an operation switch and a hot / cold switch.

[0002]

2. Description of the Related Art Conventionally, when a heat exchanger having a heat exchanger and an electric water shutoff valve arranged in the water channel, a heater for heating the heat exchanger, and an operating knob in the "operating" position are used. There is known a water heater having an operation switch for opening an electric water shutoff valve and a hot and cold water changeover switch which enables the heater when the hot and cold water changeover knob is set to the "hot water" position. In this water heater, water is discharged when the hot and cold water switch knob is in the "water" position and the operating knob is in the "active" position, and when the hot water switch knob is in the "hot water" position and the operating knob is in the "active" position. Discharge. In this water heater, even when the operation knob is in the "stop" position, the hot water / water switching knob can be changed from the "hot water" position to the "water" position and from the "water" position to the "hot water" position (however, Hot water will not be discharged when the operation knob is in the "stop" position).

[0003]

However, the conventional water heater has the following drawbacks. While hot water is being discharged (hot water / water switching knob is in the “hot” position, operation knob is in the “active” position), when the operation knob is in the “stop” position, hot water discharge is stopped, but the hot / water switching knob is in the “hot water” position. To maintain. here,
If the user leaves the water heater and the user cannot monitor the water heater (for example, when he / she is away or in the middle of the night), in the unlikely event that foreign matter adheres (when a cockroach etc. is caught on the operation switch), contact fusion, or contact covering When water or the like is generated and the contact point of the operation switch is turned on, hot water remains in the water heater, which is a safety problem. An object of the present invention is to provide an instantaneous water heater having an operation switch and a hot and cold water changeover switch, in which the operation switch opens the electric stop valve even when the operation operation knob or the operation knob is in the “stop” position. It is to provide a water heater in which the heating means does not operate (the hot water is not discharged) even when the problem of instructing occurs.

[0004]

In order to solve the above problems, the present invention adopts the following configurations. (1) A heat exchange channel in which a water supply pipe, a heat exchanger, and a hot water outlet pipe are arranged in a row, and an electric water shutoff valve is provided in the channel, a heating means for heating the heat exchanger, and a driving operation knob Operation in which the operation knob is instructed to open the electric water stop valve when the operation operation knob is in the "operation" position, and instructed to close the electric water stop valve when the operation operation knob is in the "stop" position. It operates by operating the switch and hot and cold water switching knob,
A hot water supply device provided with a hot / cold water changeover switch that enables the heating means when the hot water / water changeover knob is in the "hot water" position, and disables the heating means when in the "water" position. Is in the “stop” position,
The hot and cold water switching knob is always held in the "water" position. (2) A heat exchange water passage in which a water supply pipe, a heat exchanger, and a hot water discharge pipe are arranged in a row, and an electric water shutoff valve is provided in the water passage, heating means for heating the heat exchanger, and the electric stop. An operation switch for switching an instruction to open and close a water valve, a hot and cold water switching switch for switching an instruction to enable and disable the heating means, and the operation switch to stop the electric shutoff. "Stop" position for instructing the closing of the valve, the hot and cold water changeover switch deactivating the heating means, the operation switch for instructing the opening of the electric water shutoff valve, and the hot and cold water changeover switch for the heating The "water" position at which the means is inoperable and the "hot water" position at which the operation switch instructs the opening of the electric water shutoff valve and the hot and cold water changeover switch enables the heating means can be freely set. With single operation knob That. (3) A heat exchange channel in which a water supply pipe, a heat exchanger, and a hot water outlet pipe are provided in series, and an electric water shutoff valve is provided in the water channel, heating means for heating the heat exchanger, and the heating means. Hot water temperature controller for controlling at least one of the heat generation amount of the water or the amount of water flowing into the water supply pipe, an operation switch for switching between an opening instruction and a closing instruction of the electric water shutoff valve, and operating the heating means. A hot water switch for switching between an enabling instruction and an inoperable instruction, the operation switch instructing closing of the electric water shutoff valve, and the hot water switching switch inactivating "stopping" the heating means. "Water" at the position and the operation switch instructing the opening of the electric water shutoff valve, and the hot water changeover switch deactivating the heating means
A single operation knob capable of freely setting a position and a "hot water" position in which the operation switch instructs opening of the electric water shutoff valve and the hot water changeover switch enables the heating means, At the "hot water" position, the tap water temperature controller is operated in accordance with the operation knob operation amount.

[0005]

[Action]

[Claim 1] When the operating knob is in the "operating" position,
Moreover, when the hot and cold water switching knob is at the "water" position, the electric water shutoff valve is opened and the heating means is not activated, so that water is discharged from the hot water discharge pipe. When the operation control knob is in the "operation" position and the hot and cold water switching knob is in the "hot water" position, the electric water shutoff valve is opened and the heating means is activated, so that hot water is discharged from the hot water pipe.
When the operation knob is in the "stop" position, foreign matter adheres (when cockroaches are caught on the operation switch), contact fusion, or water contact occurs, causing the operation switch to open the electric shutoff valve. Even if the problem of instructing the valve occurs, since the hot and cold water switching knob is held at the "water" position, water is discharged from the hot water outlet pipe, but the heating means does not operate. [Claim 2] When the operation knob is in the "stop" position, neither hot water nor hot water is discharged from the hot water outlet pipe. The operation knob is "water"
When in the position, the electric water shutoff valve is opened and water is discharged from the hot water pipe. When the operation knob is at the "hot water" position, the electric water shutoff valve is opened and the heating means is activated, so that hot water is discharged from the hot water outlet pipe. When the operation knob is in the "stop" position, even if there is a problem that foreign matter adhesion, contact fusion, contact water immersion, etc. occur and the operation switch instructs the electric shutoff valve to open, Since the hot water switching switch disables the heating means, water is discharged from the hot water outlet pipe, but the heating means does not operate. [Claim 3] When the operation knob is at the "stop" position, neither hot water nor hot water is discharged from the hot water outlet pipe. The operation knob is "water"
When in the position, the electric water shutoff valve is opened and water is discharged from the hot water pipe. When the operation knob is in the "hot water" position, the electric water shutoff valve is opened and the heating means is activated, so that hot water is discharged from the hot water discharge pipe. Further, the hot water temperature controller is operated in accordance with the operation amount of the operation knob. When the operation knob is in the "stop" position, even if there is a problem that foreign matter adheres, contact fusion, or contact water gets wet and the operation switch indicates the opening of the electric shutoff valve, Since the changeover switch makes the heating means inoperable, water is discharged from the hot water pipe, but the heating means does not operate.

[0006]

【The invention's effect】

[Claim 1] During a period when the user leaves the water heater and the user cannot monitor the water heater (for example, absence or midnight),
In the unlikely event that foreign matter adheres (when a cockroach etc. is caught on the operation switch), contact fusion, or contact water gets wet, the operation switch is electrically stopped even though the operation knob is in the "stop" position. Even if a problem of instructing to open the valve occurs, the heating means does not operate and hot water is not discharged from the hot water discharge pipe, which is safe. [Claim 2] If the user leaves the water heater and the user cannot monitor the water heater, foreign matter adhesion, contact fusion, contact water contact, etc. should occur and the operation knob should "stop". Even if the operation switch instructs the opening of the electric water shutoff valve regardless of the position, it is safe because the heating means does not operate and hot water is not discharged from the hot water discharge pipe. Discharge can be stopped, water can be discharged, and hot water can be discharged with a single operation knob. [Claim 3] When the user leaves the water heater and the user cannot monitor the water heater, foreign matter adhesion, contact fusion, contact water contact, etc. should occur and the operation knob should "stop". Even if the operation switch instructs the opening of the electric water shutoff valve regardless of the position, it is safe because the heating means does not operate and hot water is not discharged from the hot water discharge pipe. Discharging can be stopped, water can be discharged, and hot water can be discharged with a single operation knob, and the hot water temperature can be adjusted when the hot water is discharged.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention (corresponding to claim 3) will be described with reference to FIGS. As shown in FIG. 1, FIG. 3, and FIG. 4, the water heater A has a water supply pipe 11, a heat exchanger 12, and a hot water discharge pipe 13 which are successively connected in this order.
Heat exchange channel 1 in which an electric shutoff valve 14 driven by 41 is arranged
A heating device 2 having a gas burner 21 that heats the heat exchanger 12, a control unit 3, and a motor 141 that opens and closes the electric shutoff valve 14, and an operation switch 4 that switches between forward rotation and reverse rotation. Operation to determine the "stop", "water", and "hot water" positions by freely sliding the hot and cold water changeover switch 5 that operates the gas burner 21 in the contact closed state (however, the contact of the water flow switch 241 is also closed). In association with the knob 6 and the slide of the operation knob 6 at the "hot water" position of the operation knob 6, the hot water temperature control means 31 (see FIG. 5) for controlling the heat generation amount of the gas burner 21 and / or the amount of water flowing to the water supply pipe 11 is provided. Shown) and.

As shown in FIG. 4, the water supply pipe 11 has a water governor valve 1 that functions not only as an electric shutoff valve 14 but also as a water pressure responsive member.
11, a water amount control valve 112 is arranged in that order. The outlet pipe 13 also shown in FIG. 1 is configured by covering a metal flexible pipe with a resin pipe, and a shower head 131 is fitted to the tip thereof. A water flow switch 132 is attached to the shower head 131 so that a shower or a straight water flow 133 can be selected.

As shown in FIG. 4, the heating device 2 controlled by the control unit 3 is provided in the gas burner 21, the gas conduit 22 for supplying the fuel gas g to the gas burner 21, and the gas conduit 22. , Electromagnetic safety valve 23, water governor valve 1
It is composed of a water pressure responsive valve 24 that opens by the operation of 11 to close the water flow switch 241, a gas governor valve 25, a gas amount control valve 26, and a sparker 331 provided in an appropriate position of the gas burner 21.

As shown in FIG. 3, the control unit 3 receives the outputs of the thermocouple 321 and the frame rod 322 as input and maintains the combustion of the gas burner 21.
2 and the operation of the sparker 331 are controlled, and the gas burner 21
The ignition control circuit 33 for igniting, the safety valve drive circuit 34 for closing the electromagnetic safety valve 23 in the case of abnormal combustion, and the motor 141 for driving the electric shutoff valve 14 are energized to rotate the motor 141 in the normal direction or Reverse water stop valve drive circuit 35
Composed of and.

As shown in FIG. 3, the operating switch 4 is a switching type micro switch which is operated by sliding operation of the operating knob 6. As shown in FIG. 3, the operating knob 6 has the "water" position or the "hot water". When in position, common terminal (c)
Is connected to the contact (a). In this case, the forward rotation drive terminal 35a of the water shutoff valve drive circuit 35 is energized, and the motor 1
41 gradually opens the electric water shutoff valve 14,
The target opening (valve open state), the upper limiter 351 which is a normally closed switch is closed and the water shutoff valve drive circuit 35 is closed.
To the motor 141 is stopped, and the motor 141 is stopped. Also,
When the operating knob 6 is in the "stop" position, the common terminal (c) is connected to the contact (b). In this case, the reverse rotation drive terminal 35b of the water shutoff valve drive circuit 35 is energized, and the motor 14
No. 1 gradually closes the electric water stop valve 14, and when the electric water stop valve 14 reaches the target opening (closed state), the lower limiter 352, which is a normally closed switch, opens and the water stop valve drive circuit. The power supply to 35 is stopped, and the motor 141 is stopped.

The hot and cold water changeover switch 5 is a normally open type micro switch which is operated by sliding operation of the operation knob 6. As shown in FIG. 2, when the operation knob 6 is in the "hot water" position, its contact point is closed. To achieve. Hot water switch 5
When the contact point of is closed and the water flow switch 241 is also closed, the combustion state detection circuit 32 and the ignition control circuit 3
3, and the safety valve drive circuit 34 is also energized.

The operation knob 6 is a hot water temperature for mechanically adjusting the switch operation mechanism 60 for mechanically pressing the stems of the operation switch 4 and the hot and cold water changeover switch 5, and the gas amount adjusting valve 26 and the water amount adjusting valve 112. Control means 31
(See FIG. 5), the switch operating mechanism 60 is
In the "stop" position range 61 of the operation knob 6, the common terminal (c) of the operation switch 4 and the contact (b) are conducted to open the contact of the hot and cold water changeover switch 5, and the "water" position range 6
In step 2, the common contact (c) and the contact (a) of the operation switch 4 are brought into conduction to open the contact of the hot and cold water changeover switch 5, and in the "hot water" position range 63, the contact and the common contact (c) of the operation switch 4 are contacted. (A) is conducted to bring the contact of the hot and cold water changeover switch 5 into a closed state. Further, in the "hot water" position range 63 of the operation knob 6, the tap water temperature control means 31 is operated so that the set temperature becomes the lowest at the left end of the operation range 63 and the set temperature becomes the highest at the right end.

Next, the operation of the water heater A will be described. When the operation dial 6 is in the "stop" position range 61, the switch operating mechanism 60 releases the pressure on each stem and only the reverse rotation drive terminal 35b of the water shutoff valve drive circuit 35 is energized. 14 is controlled to be closed (water flow switch 241
Open), the electromagnetic safety valve 23 maintains the closed state. Here, if the user leaves the water heater and the user cannot monitor the water heater (for example, when he / she is away or at midnight), foreign matter should be attached (cockroaches enter the water heater A and get caught in the operation switch 4). In case of contact), fusion of contacts, or water exposure,
When the common terminal (c) of the operation switch 4 is electrically connected to the contact (a), the electric water shutoff valve 14 is opened and the shower head 131 is opened.
Although the water is discharged from the tank, the contact of the hot water switching switch 5 maintains the open state, so that the combustion of the gas burner 21 is not started (the hot water is discharged).

When the operating dial 6 is in the "water" position range 62, the switch operating mechanism 60 pushes the stem of the operating switch 4, and the operating switch 4 contacts the common terminal (c) and the contact (a).
And become conductive. Therefore, the forward rotation drive terminal 35a of the water stop valve drive circuit 35 is energized, the electric water stop valve 14 is opened, and water is discharged from the shower head 131 (the water flow switch 241 is closed).

When the operating knob 6 is in the "hot water" position range 63, the switch operating mechanism 60 presses the stems of the operating switch 4 and the hot and cold water changing switch 5, and the operating switch 4 contacts the common terminal (c) and the contact ( The contact with the hot and cold water changeover switch 5 is closed. Therefore, the forward rotation drive terminal 35a of the water stop valve drive circuit 35 is energized, and when the water flows, the water flow switch 241 is also closed.
The combustion state control circuit 32, the ignition control circuit 33, and the safety valve drive circuit 34 are energized, and the shower head 131
Hot water is discharged from the. Further, in the "hot water" position range 63 of the operation knob 6, the closer the operation knob 6 is to the left end in the drawing, the more the water temperature increases or the gas amount decreases, or the combination thereof lowers the water temperature of the water flow 133 to approach the right end in the drawing. As the amount of gas increases, the amount of water decreases, or a combination thereof, the hot water temperature of the water flow 133 increases.

The advantages of the water heater A will be described below. (A) A period in which the user leaves the water heater and the user cannot monitor the water heater (when the operation switch 4 instructs the electric shutoff valve 14 to close and the contact point of the hot water switch 5 is in the open state), Cockroaches intrude into the water heater A and the operation switch 4
Even if the operation switch 4 commands the opening of the electric water shutoff valve 14 due to catching on the stem of the engine, fusion of contacts, or occurrence of water, etc., the contact of the hot and cold water changeover switch 5 maintains the open state. Therefore, it is safe because only the water is discharged from the shower head 131 and the gas burner 21 does not start burning. (A) With one operation knob 6, the discharge of water or hot water from the shower head 131 can be stopped, the water can be discharged, and the hot water can be discharged, and the hot water temperature can be adjusted when the hot water is discharged.
Has excellent operability.

Next, a second embodiment of the present invention (corresponding to claim 3) will be described with reference to FIGS. 6, 3 and 4. 6,
As shown in FIG. 3 and FIG. 4, the water heater B has a water supply pipe 11, a heat exchanger 12, and a hot water discharge pipe 13 which are sequentially connected to each other.
1, a heat exchange channel 1 in which an electric shutoff valve 14 driven by a motor 141 is arranged, a heating device 2 having a gas burner 21 for heating the heat exchanger 12, a control unit 3, and an electric shutoff valve. An operation switch 4 for switching between forward rotation and reverse rotation by energizing a motor 141 for opening and closing 14 and a hot and cold water switching switch 5 for operating the gas burner 21 in a contact closed state (however, the contact of the water flow switch 241 is also closed). , The operation knob 6 that can freely set the “stop”, “water”, and “hot water” positions by rotating it, and the amount of heat generated by the gas burner 21 in conjunction with the rotation of the operation knob 6 at the “hot water” position, And / or hot water temperature control means 3 for controlling the amount of water flowing into the water supply pipe 11.
1 and 1.

In this embodiment, the operation knob 6 is connected to a switch operation mechanism (not shown) for mechanically pressing the stems of the operation switch 4 and the hot and cold water changeover switch 5, and the switch operation mechanism is operated. At the "stop" position 61a of the knob 6, the common terminal (c) and contact (b) of the operation switch 4
And the contact of the hot and cold water changeover switch 5 are closed, and the common terminal (c) and the contact (a) of the operation switch 4 are brought into conduction in the "water" position range 62, and the contact of the hot and cold water changeover switch 5 is turned on. In the open state, the common terminal (c) of the operation switch 4 and the contact point (a) are brought into conduction in the “hot water” position range 63, and the contact point of the hot water switch 5 is closed. Further, only the "hot water" position range 63 is provided with hot water outlet temperature control means 31 connected to the operation knob 6. further,
When it is desired to stop the use after the use in the illustrated (high) position of the "hot water" position range 63, the "stop" position 61a is passed through the illustrated (low) position of the "hot water" position range 63 and the "water" position range 62.
It is possible to return the operation knob 6 directly from the illustrated (high) position to the "stop" position 61a so that the operation knob 6 does not have to be returned.

The water heater B of this embodiment has the same advantages as (A) and (A) of the water heater A. Further, the operation knob 6 is changed from the "hot" position range 63 to the "water" position range. It has the advantage (c) that it can also be returned directly to the "stop" position 61a without going through 62.

Next, a third embodiment of the present invention (corresponding to claim 2) will be described with reference to FIGS. 7, 3 and 4. 7,
As shown in FIGS. 3 and 4, when the operation knob 6 is at the "hot water" position 63a, the temperature of the hot water discharged from the shower head 131 is connected to the hot water temperature control means 31. It can be changed by rotating 64.

The water heater C of this embodiment has the following advantages in addition to the advantage (a). (D) Since the temperature control knob 64 is provided separately from the operation knob 6, the set hot water temperature set by the temperature control knob 64 does not change each time it is used. (E) Since the center part of the slide groove 600 excluding the left end and the right end is the “stop” position range 61, when it is desired to use hot water, the “hot” position 63a is directly fed from the “stop” position range 61.
Can be

Next, a fourth embodiment of the present invention (corresponding to claim 3) will be described with reference to FIGS. 8, 3 and 4. In the water heater D of the present embodiment, when the operation knob 6 is in the "hot water" position range 63, the temperature of the hot water discharged from the shower head 131 can be changed by the tapping temperature control means 31 connected to the operation knob 6.

The water heater D of this embodiment has the above (a),
It has advantages similar to those of (a) and (e).

Next, a fifth embodiment of the present invention (corresponding to claim 3) will be described with reference to FIGS. 9, 10, 3 and 4. As shown in FIGS. 9, 10, 3, and 4, the water heater E
Slides left and right and diagonally to "stop",
The operation knob 6 for selecting the "water" and "hot water" positions is provided.

Further, the "water" position range 62 is blue, "hot water"
The position range 63 is colored deeper red to the right, and the hot water temperature is also displayed.

The water heater E of this embodiment has the above (a),
In addition to the advantage (a), there is an advantage (f) that the operability is excellent because it is graphed.

Next, a sixth embodiment of the present invention (corresponding to claim 1) will be described with reference to FIGS. 11, 12, 3 and 4. As shown in FIG. 11, FIG. 12, FIG. 3, and FIG. 4, the water heater F is pressed and held when pressed as indicated by an arrow 41, and at this position, the common contact (c) and the contact (a) of the operation switch 4 are connected. And the water discharge knob 40 that is made to conduct, are pressed and held together with the water discharge knob 40. At this position, the common terminal (c) of the operation switch 4 and the contact point (a) are made conductive, and the hot and cold water changeover switch Hot water discharge knob 50 that closes the contact point 5 and temperature control knob 64 that is connected to the hot water discharge temperature control means that changes the temperature of the hot water discharged from the shower head 131.
With.

Numeral 8 is a push-push mechanism having a known structure itself, and in this embodiment, it operates as follows. When the water discharge knob 40 is pressed, the operation switch 4 is brought into conduction between the common terminal (c) and the contact (a), and the shower head 131
Water is discharged from. When the hot water discharge knob 50 is pressed, in the operation switch 4, the common terminal (c) and the contact (a) are brought into conduction, the contact of the hot water switch 5 is closed, and hot water is discharged from the shower head 131. When the water discharge knob 40 is pressed in the above state, the operation switch 4 is brought into conduction between the common terminal (c) and the contact (b), and water stops. When the hot water discharge knob 50 is pressed in the above state, the water discharge knob 4
When 0 is also pressed, the operation switch 4 connects the common terminal (c) and the contact (b), the hot and cold water changeover switch 5 is opened, and the hot water is stopped.

The water heater F of this embodiment has the above (a),
It has advantages similar to (d).

[Brief description of drawings]

FIG. 1 is an external view of a water heater according to a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a relationship between an operation knob and an operation switch, a hot / cold water changeover switch, etc. in the water heater.

FIG. 3 is an electrical connection diagram of a water heater common to the first to sixth embodiments of the present invention.

FIG. 4 is a structural explanatory view of a water heater common to the first to sixth embodiments of the present invention.

FIG. 5 is an enlarged view of a main part of the water heater according to the first embodiment of the present invention.

FIG. 6 is an external view of a water heater according to a second embodiment of the present invention.

FIG. 7 is an external view of a water heater according to a third embodiment of the present invention.

FIG. 8 is an external view of a water heater according to a fourth embodiment of the present invention.

FIG. 9 is an external view of a water heater according to a fifth embodiment of the present invention.

FIG. 10 is an enlarged view of a main part of the water heater.

FIG. 11 is an external view of a water heater according to a sixth embodiment of the present invention.

FIG. 12 is an enlarged view of a main part of the water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat exchange channel 2 Heating device (heating means) 4 Operation switch 5 Hot water changeover switch 6 Operation knob 11 Water supply pipe 12 Heat exchanger 13 Hot water discharge pipe 14 Electric shutoff valve 31 Hot water temperature control means (hot water temperature controller) 40 Water discharge Picking (Driving operation picking) 50 Hot water discharge picking (Hot water switching picking)

Claims (3)

[Claims] 1. A heat exchange water passage in which a water supply pipe, a heat exchanger, and a hot water discharge pipe are connected in series, and an electric water shutoff valve is provided in the water passage, a heating means for heating the heat exchanger, and an operation. It operates by the operation of the operation knob, and when the operation operation knob is in the "operating" position, it instructs the opening of the electric water shutoff valve, and when it is in the "stop" position, it instructs the closing of the electric water shutoff valve. It operates by the operation switch and the operation of the hot and cold water switching knob. When the hot and cold water switching knob is in the "hot water" position, the heating means is operable, and when it is in the "water" position, the heating means is inoperative. A water heater having a hot and cold water changeover switch, wherein the hot and cold water changeover knob is always held at the "water" position when the operation operation knob is at the "stop" position. 2. A heat exchange channel having a water supply pipe, a heat exchanger, and a hot water outlet pipe connected to each other, and an electric water shutoff valve provided in the water channel; a heating unit for heating the heat exchanger; An operation switch that switches between an opening instruction and an closing instruction of the electric water shutoff valve; a hot and cold water switching switch that switches between an instruction that enables the heating means and an instruction that disables the heating means; A "stop" position instructing the closing of the water shutoff valve, the hot water switching switch deactivating the heating means, and the operation switch instructing the opening of the electric water shutoff valve, and the hot water switching switch The "water" position that disables the heating means and the "hot water" position that allows the operation switch to instruct the opening of the electric water shutoff valve and the hot-water switching switch that enables the heating means Single configurable operation Water heater which is provided with the Mito. 3. A heat exchange channel having a water supply pipe, a heat exchanger, and a hot water outlet pipe connected in series, wherein a water shutoff valve is provided in the water channel, and heating means for heating the heat exchanger, A hot water outlet temperature controller that controls at least one of the amount of heat generated by a heating unit or the amount of water that flows in the water supply pipe; an operation switch that switches between an opening instruction and an closing instruction of the electric water shutoff valve; A hot water switching switch that switches between an instruction to enable and a command to disable the operation, the operation switch instructs to close the electric water shutoff valve, and the hot water switching switch disables the heating means. "Stop" position, the operation switch directs opening of the electric water shutoff valve, the hot water switch deactivates the heating means, and the operation switch operates the electric water shutoff valve. Instruct to open the valve The hot water changeover switch is provided with a single operation knob capable of freely setting the "hot water" position enabling the heating means to be operated, and at the "hot water" position, the hot water temperature control is performed corresponding to the operation knob operation amount. A water heater whose water heater is operated.