JPH0796971B2 - Hot water heater with additional heating function - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a water heater with a reheating function for automatically supplying hot water to a bathtub.

2. Description of the Related Art In recent years, a water heater with a reheating function has been developed that combines a water heater and a bathtub and combines a reheating machine that circulates hot water with a pump. The automation of baths such as added ones is progressing.

A conventional water heater with a reheating function will be described below with reference to the drawings. FIG. 4 shows a schematic diagram of the configuration of the conventional example.

A heat exchanger 1 for hot water supply is connected to the water supply port 1a and the hot water supply port 1b. Reference numeral 2 denotes a heat exchanger for additional heating, which is connected to the hot water return port 2a and the hot water outlet port 2b. A pump 3 is provided in the hot water passage from the hot water return port 2a to the heat exchanger 2 for additional heating, and a bath 4 is connected to the hot water return port 2a and the hot water outlet port 2b by a connecting pipe 5 to form a hot water circulation passage. To do. An exhaust pipe 6 is connected to each of the heat exchangers 1 and 2, and a combustion exhaust gas is discharged to an exhaust port 8 by an exhaust fan 7. Further, it is formed in a part of the case so that the combustion air can be supplied from the air supply port 9. The fuel passage branches from the original solenoid valve 11,
Burner 14 for hot water supply through solenoid valve 12 for hot water supply and proportional control valve 13
In addition, it is connected to a heating burner 16 through a heating solenoid valve 15.

Water supply detection element 17 that detects water supply in the water supply side passage and outputs a signal
And a hot water supply thermistor 18 is provided at the outlet of the hot water supply heat exchanger 1.

A circulating water detecting element 19 for detecting circulation of hot water is provided in a hot water passage leading to the pump 3 and the heat exchanger 2 for additional heating, and a thermistor 20 for additional heating is provided at an inlet of the heat exchanger 2 for additional heating.
To provide. The hot water supply 21 is connected to the hot water supply port 1b through, for example, a hot water supply pipe 22 to a bathroom or a kitchen, and an automatic hot water supply unit 23 having a hot water supply control valve 24, a hopper 25 and a water level sensor 26 for automatically supplying hot water to the bathtub is supplied. It is branched from the pipe 22 and connected to the bathtub 4.

The actuator (electromagnetic valve, pump, etc.) is configured to be operated by the control circuit 27 and the remote controller 28 in response to signals from the various sensors.

Next, the operation will be explained. By opening the hot water dispenser 21,
The water supply detection element 17 operates to operate the original solenoid valve 11 and the hot water supply solenoid valve.
12. Proportional control valve 13 opens to ignite the hot water supply burner 14 and the hot water supply thermistor 18 signals to control the hot water temperature.
The previous period proportional control valve 13 is operated by the output calculated by the control circuit 27 so that the hot water supply temperature set by the hot water supply hot water temperature setter 28 (not shown) is reached, and the combustion amount of the hot water supply burner 14 is set. Is controlled to stably control the hot water temperature.

On the other hand, by operating a reheating switch (not particularly shown) provided on the remote controller 28, the pump 3 is operated to circulate the water or hot water previously stored in the bathtub 4, and the circulating water detection element
19 operates, the original solenoid valve 11 and the solenoid valve 15 for additional heating are opened, and the burner 16 for additional heating is ignited.

Detecting the circulating hot water temperature, the signal from the additional heating thermistor 20 installed at the entrance of the additional heat exchanger 2 and the remote control
The control circuit 27 is operated so that the bath boiling temperature set by the bathtub hot water temperature setting device (not shown) of 28, the solenoid valve 15 for additional heating, and the combustion amount of the burner 16 for additional heating Is controlled to stably control the circulating hot water to control the bath water temperature.

Further, when an automatic hot water supply switch (not shown) provided on the remote controller 28 is operated, a hot water supply control valve of the automatic hot water supply unit 23.
The proportional control valve 13 is operated with the output processed by the control circuit 27 so that the valve 24 is opened and the automatic hot water supply temperature is set by the hot water supply hot water temperature setting device (not shown) of the remote controller 28. By controlling the combustion amount of the hot water supply burner 14 to stably control the hot water supply temperature, automatic hot water supply to the bathtub 4 and automatic temperature control of the bath temperature are realized.

However, in the above-described configuration, the automatic hot water supply unit 23 needs to be installed in the immediate vicinity of the bathtub 4, and due to the configuration of the building, the installation is not possible when the bathroom is in the center of the room. In addition to being impossible, even if it could be installed on the wall side, there were problems such as a defect in appearance and aesthetics of the building.

In view of the above problems, the present invention intends to provide an automatic hot water supply function that is inexpensive and inexpensive in installation and is effective in terms of workability and aesthetics.

Means for Solving the Problems In order to solve the above problems, a water heater with an additional heating function of the present invention is a hot water circulation passage that is connected to a hot water heat exchanger and a bathtub and circulates hot water with a pump. Controller, a proportional control valve connected in series with the original solenoid valve, and a hot water supply solenoid valve branched from the proportional control valve and connected to each of the hot water supply burner and the additional heating burner desired for each heat exchanger. And a solenoid valve for reheating and a hot water supply thermistor for detecting the hot water supply temperature provided at the outlet of the hot water supply heat exchanger, and a hot water supply for circulating hot water and automatic hot water supply provided at the inlet of the hot water supply thermistor and the reheating heat exchanger. A hot-water thermistor for detecting the temperature, a bathtub automatic hot water supply path having a hot water supply flow rate control valve branched from the hot water supply passage downstream of the hot water supply thermistor and connected to the hot water circulation passage, and the hot water supply heat exchanger. A water supply unit that calculates and measures the water supply amount provided in the water supply passage A water detection element and a control circuit are provided, and during the automatic hot water supply operation, the control circuit opens the hot water supply flow rate control valve, and the control signal is processed by signals of both the hot water supply thermistor and the reheating thermistor, The proportional control valve is operated to control the combustion amount of the hot water supply burner, and when the water temperature is low such as in the winter season or when the hot water supply plug is used, the hot water supply capacity is exceeded, and the automatic hot water supply temperature to the bathtub is controlled by the boiling water. When the temperature becomes lower than the set temperature, the hot water supply thermistor becomes lower than the heating thermistor, and the difference between the signals of the both thermistors becomes large, the additional heating solenoid valve is also opened and the additional heating is performed. The burner for combustion is also configured to burn at the same time to automatically supply hot water to the bathtub, and the hot water supply detection element closes the hot water supply flow rate control valve at an arbitrary set amount to stop automatic hot water supply.

With the above-described structure, the present invention stabilizes the hot water temperature by controlling the combustion amount of the hot water burner by operating the proportional control valve with the output of the control circuit in accordance with the signal of the hot water supply thermistor during hot water supply operation. In addition to the above, the proportional control valve is operated by the output processed by the control circuit in response to the signal from the heating thermistor during heating operation to control the combustion amount of the heating burner and stabilize the bath water temperature. Can be controlled. In addition, during simultaneous operation, the control circuit gives priority to the operation of the hot water supply mode to operate the proportional control valve to control the hot water supply water temperature in a stable manner, and the reheating side uses the signal from the heating thermistor for additional heating. By controlling the opening and closing of the solenoid valve for use, the bath water temperature can be controlled stably.

Furthermore, during the automatic hot water supply operation, the hot water supply flow control valve is opened to automatically supply hot water from the hot water heat exchanger to the bathtub through the additional heat heat exchanger, and the automatic hot water temperature is added to the hot water supply thermistor. By operating the proportional control valve with the output processed by the control circuit by both signals of, the combustion amount of the hot water supply burner is controlled and the bath water temperature is brought to the desired bath boiling temperature without additional heating. It can be completed only by automatic hot water supply operation.

Also, when the water temperature is low, such as in winter, or by using multiple taps of the hot water supply system, the hot water supply capacity is exceeded and the temperature of the hot water supplied to the bathtub becomes lower than the temperature set above the bath boiling temperature. When the difference between the thermistor signals becomes large, the solenoid valve for additional heating is opened and the additional burner is also burned at the same time. Automatic hot water can be supplied to the desired bath boiling temperature in a short time.

In addition, the number of parts can be reduced, the automatic hot water supply function can be made inexpensive, and the installation can be made free, and the workability and aesthetics can be effectively achieved to achieve the purpose.

Embodiment An embodiment of the present invention will be described below with reference to the schematic configuration diagram of FIG. Reference numeral 1 is a heat exchanger for hot water supply, which is connected to the water supply port 1a and the hot water supply port 1b, and has a water supply detection element (a water amount sensor for counting the amount of water, etc.) 17 which detects water supply in the water supply side passage and outputs a signal. Reference numeral 2 denotes a heat exchanger for additional heating, which is connected to the hot water return port 2a and the hot water outlet port 2b.

A pump 3 and a circulating water detecting element 19 for detecting circulation of hot water are provided in a hot water passage extending from the hot water return port 2a to the heat exchanger 2 for additional heating.
Furthermore, a bathtub 4 is connected to the warm water return port 2a and the warm water outlet port 2b by a connecting pipe 5 to form a warm water circulation passage. An exhaust pipe 6 is connected to each of the heat exchangers 1 and 2, and a combustion exhaust gas is discharged to an exhaust port 8 by an exhaust fan 7. Further, it is formed in a part of the case so that the combustion air can be supplied from the air supply port 9. The fuel passage is the original solenoid valve 11
And the proportional control valve 13 are connected in series, and the proportional control valve 13 is commonly connected to the hot water supply burner 14 through the hot water supply solenoid valve 12 and the additional heating burner 16 through the additional heating solenoid valve 15 branching from this. Branch connection as described.

Next, description will be given according to the schematic diagram of the control circuit configuration in FIG. Hot water supply thermistor 18 provided at the outlet of the hot water supply heat exchanger 1.
Signal and the hot water supply temperature set by the hot water supply temperature setting device 31 of the remote controller 28, the comparator 32 of the control circuit 27 performs a comparative calculation, and the proportional control valve is driven by the output processed by the calculation processing unit 33. The hot water supply operation control unit 38 is configured to operate the portion 34 to operate the proportional control valve 13 to control the combustion amount of the hot water supply burner 14 to stably control the hot water temperature.

On the other hand, the bath boiling temperature set by the signal of the reheating thermistor 20 for detecting the circulating hot water temperature provided at the inlet of the reheating heat exchanger 2 and the bath water temperature setting device 35 of the remote controller 28 is set. , The comparator 36 of the control circuit 27 performs comparison calculation, and the calculation processing unit 33
The proportional control valve drive unit 34 is operated by the output processed by the above, the proportional control valve 13 is operated, the combustion amount of the additional heating burner 16 is controlled, and the circulating hot water is stably controlled to control the bath water temperature. The additional heating control unit 37 is configured to control the. still,
In order to speed up the rise of the bath water temperature, the combustion amount of the additional heating burner 16 controlled by the proportional control valve 13 is set to the bath water temperature setting device.
Up to the bath boiling temperature set by 35, when the boiling temperature is reached by controlling the maximum capacity without proportional control, the additional heating of the control circuit 27 is performed so as to close the additional heating solenoid valve 15. The operation control unit 37 is configured. The hot water supply solenoid valve 12 and the reheating solenoid valve 15 are configured as a hot water supply operation control unit 38 and a reheating operation control unit 37 so that they are opened and closed when the respective hot water temperatures are controlled.

In the simultaneous operation, the hot water supply operation control unit of the control circuit 27
The output, which is preferentially processed in the hot water supply mode in 38, operates the proportional control valve drive section 34 to operate the proportional control valve 13 to stably control the hot water supply temperature, and the reheating side is for the reheating operation. By controlling the opening / closing of the reheating solenoid valve 15 by the signal of the thermistor 20, the reheating operation control unit 37 is configured to stably control the bath water temperature.

Further, at the time of automatic hot water supply operation, the hot water circulation passage on the outlet side of the pump 3 is connected to the bathtub automatic hot water supply passage having the hot water supply flow control valve 24 in the middle and the check valve 29 on the downstream side and the safety valve (vacuum breaker) 30 on the upstream side. And the hot water supply thermistor 18 is connected downstream from the hot water supply passage. By opening the hot water supply flow rate control valve 24 in response to a signal from the automatic hot water supply operation control unit 39 of the control circuit 27, the hot water supply heat exchanger 1 and the reheating heat exchanger 2 are passed, and the hot water supply thermistor is passed. By the control signal obtained by comparing and calculating the signals of both 18 and the additional heating thermistor 20 in the respective comparators 32 and 36 of the control circuit 27,
The proportional control valve drive unit 34 is operated by the output processed by the arithmetic processing unit 33 to operate the proportional control valve 13 to control the combustion amount of the hot water supply burner 14 to stably control the automatic hot water temperature. Then, the automatic hot water supply operation control unit 39 is configured to automatically supply hot water to the bathtub 4. In addition, when the water temperature is low such as in winter or by using multiple taps of the hot water dispenser, the hot water supply capacity is exceeded, and the hot water temperature to the bathtub becomes lower than the bath boiling temperature set by the bathtub hot water temperature setting device 35. When the difference between the signals of both thermistors becomes large, the reheating solenoid valve 15 is also opened, and the reheating burner 16 is also burned at the same time, so that the bath water temperature is increased by burning with a large capacity. The automatic hot water supply operation control section 39 is configured to automatically supply hot water to the desired bath boiling temperature in a short time.

The operation of the above-described embodiment will be described. Through the hot water supply pipe 22 connected to the hot water supply port 1b, for example, a hot water supply system such as a bathroom or a kitchen
When opening 21, the hot water supply operation control unit 38 is configured so that the hot water supply detection element 17 detects the supplied water and the hot water supply operation sequence operates, and the exhaust fan 7 rotates. The original solenoid valve 11, the hot water supply solenoid valve 12, and the proportional control valve 13 are opened to hold the ignition of the fuel (the ignition holding means is not particularly shown). Then, the hot water supply burner 14 burns to heat the hot water supply heat exchanger 1, and the hot water is discharged from the hot water supply pipe 21 through the hot water supply port 1b.

The hot water temperature is detected by the hot water supply thermistor 18 and the remote control
The comparator 32 of the control circuit 27 performs a comparative calculation so that the hot water supply temperature set by the hot water supply temperature setting device 31 of 28 is reached, and the calculation processing unit 33
The proportional control valve drive unit 34 is operated by the output calculated in the above step to operate the proportional control valve 13, and the combustion amount of the hot water supply burner 14 is controlled to stably control the hot water temperature.

On the other hand, the pump 3 and the exhaust fan 7 are rotated by operating an additional heating switch (not shown) provided on the remote controller 28.

When the hot water or water stored in advance in the bathtub 4 is circulated by the pump 3, the reheating operation control unit 37 is configured so that the circulating water detection element 19 detects and the reheating operation sequence operates. Open the solenoid valve 11, the reheating solenoid valve 15, and the proportional control valve 13,
The fuel is held by ignition (the ignition holding means is not specifically shown).

Then, the additional heating burner 15 burns to heat the additional heating heat exchanger 2, and the circulating hot water equal to the hot water temperature in the bathtub 4 is supplied from the hot water outlet port 2b through the connecting pipe 5 to the signal of the additional heating thermistor 20. The comparator 36 of the control circuit 27 performs comparative calculation so that the bath boiling temperature set by the bathtub hot water temperature setting device 35 of the remote controller 28 is obtained, and the proportional control valve drive unit is operated by the output of the arithmetic processing unit 33. 34 is operated to operate the proportional control valve 13 to control the combustion amount of the additional heating burner 16 to stably control the circulating hot water to control the bath water temperature.

In addition, in order to speed up the rise of bath water temperature, the proportional control valve 13
The amount of combustion of the additional heating burner 16 controlled by up to the bath boiling temperature set by the bath water temperature setting device, when the boiling temperature is reached by controlling the maximum capacity without proportional control,
The additional solenoid valve 15 is closed.

When the automatic hot water supply operation switch provided in the recommon 28 is operated, the hot water supply flow control valve 24 is opened, and the hot water heat exchanger 1 and the reheating heat exchanger 2 are passed from the hot water outlet 2b to the bathtub 4. Hot water is automatically supplied.

The automatic hot water supply operation control unit 39 is configured so that the water supply detection element 17 detects the supplied water and operates the automatic hot water supply operation sequence, and the exhaust fan 7 rotates. At that time, the pump 3 is not rotated.

The original solenoid valve 11, the hot water supply solenoid valve 12, and the proportional control valve 13 are opened to hold the ignition of the fuel (the ignition holding means is not particularly shown). Then, the hot-water supply burner 14 burns to heat the hot-water supply heat exchanger 1, and the hot-water supply flow control valve 24, the bathtub automatic hot water supply passage, and the reheating heat exchanger 2 are used to automatically supply hot water from the hot water outlet 2b to the bathtub 4. To be done.

The automatic hot water temperature is detected by both the hot water supply thermistor 18 and the additional heating thermistor 20, and the bath water temperature setting device 35 of the remote control 28 is detected.
Control circuit so that the bath boiling temperature set by
In accordance with the control signals comparatively calculated by the comparators 32 and the comparators 36 of 27, the proportional control valve drive unit 34 is operated and the proportional control valve 13 is operated by the output processed by the arithmetic processing unit 33 to operate the hot water supply burner 14. The amount of combustion is controlled to stably control the temperature of the automatic hot water supply and the hot water is automatically supplied to the bathtub 4.

In this way, the burner for hot water supply is generated by the signal from the thermistor 20 for additional heating.
The control of the combustion amount of 14 is, for example, the hot water supply thermistor.
Even if 18 and the thermistor 20 for additional heating are made to have the same specifications, the characteristics of the thermistor 18 for hot water supply differ depending on the variations in the parts. Since the bath boiling temperature may not be reached, controlling the combustion amount of the hot water supply burner 14 with the signal from the additional heating thermistor 20 ensures that the desired bath boiling temperature is set by the bath water temperature setting device. Because you can.

By doing so, it is possible to complete the operation only by the automatic hot water supply operation without the operation of heating the bath to the desired bath boiling temperature.

At this time, since the pump 3 is not rotating, the hot water heated by the hot water heat exchanger 1 is automatically supplied from the hot water outlet 2b to the bathtub 4 through the hot water heat exchanger 2 so that the hot water thermistor is heated.
It is possible to control the combustion amount of the hot water supply burner 14 with 20 signals.

Also, when the water temperature is low such as in winter or by using multiple taps of the hot water dispenser, the hot water supply capacity is exceeded, and the hot water temperature to the bathtub becomes lower than the bath boiling temperature set by the bathtub hot water temperature setting device 35. When the difference between the signals of both thermistors becomes large, the additional heating solenoid valve 15 is also opened and the additional heating burner is opened.
By burning 16 at the same time and burning with high capacity, it is possible to automatically supply hot water to the desired bath boiling temperature in a short time.

The amount of hot water supplied to the bathtub 4 uses a water amount sensor that counts the amount of water supplied to the water supply detecting element 17, so it detects the amount of water for ignition and extinguishing, and the automatic hot water supply operation of the control circuit 27 during automatic hot water supply operation. The hot water supply flow rate control valve 24 can be automatically closed to automatically stop hot water supply by calculating and measuring by the control unit 39.

The check valve 29 and the safety valve (vacuum breaker) 30 are for preventing backflow into the hot water supply passage due to the rotation of the pump 3 during the additional heating operation.

Next, the automatic hot water supply operation program will be described based on the flowchart of FIG. When the automatic hot water supply operation switch (not shown) is operated, the automatic hot water supply operation program is started. By opening the hot water supply flow rate control valve 24 in step 41, the signal of the water supply detection element 17 is measured in step 42, and when the ignition water amount is detected, the automatic hot water supply operation sequence in step 43 operates and the hot water supply burner 14 operates. The hot water supply heat exchanger 1 is burnt and heated, and is automatically supplied to the bathtub 4 from the hot water outlet 2b through the hot water supply flow control valve 24, the bathtub automatic hot water supply passage, and the reheating heat exchanger 2.

The automatic hot water temperature is detected by both the hot water supply thermistor 18 and the additional heating thermistor 20, and the bathtub hot water temperature setting device of the remote controller 28 is detected.
The comparator 32 and the comparator 36 of the control circuit 27 perform comparison calculation so that the bath boiling temperature set in 35 is reached, and in steps 44 and 45, the automatic hot water temperature is controlled to the bath boiling set temperature. The water is automatically supplied. When the automatic hot water supply amount in step 46 reaches the set amount, the hot water supply flow rate control valve 24 is closed in step 47 to stop the automatic hot water supply and automatically supply hot water to the bathtub 4 to a desired bath boiling temperature in a short time. Can be done.

In addition, when the water temperature is low such as in winter or by using multiple taps of the hot water dispenser, the hot water supply capacity is exceeded, and the hot water temperature to the bathtub becomes lower than the bath boiling temperature set by the bathtub hot water temperature setting device 35. When it is detected in step 48 that the difference between the signals of both thermistors has become large, the solenoid valve 15 for additional heating is also opened in step 49, and the burner 16 for additional heating is also burned at the same time. By burning with the ability, it is possible to automatically supply hot water to the desired bath boiling temperature in a short time.

Effect of the Invention As described above, the present invention is a heat exchanger for heating a hot water circulation passage that is connected to a hot water heat exchanger and a bathtub and circulates hot water with a pump, and a proportional control valve connected in series to the original solenoid valve, A hot water supply solenoid valve and a reheating solenoid valve branched and connected from the proportional control valve to each of the hot water supply burner and the additional heating burner desired for each heat exchanger, and the hot water heat exchanger. The thermistor for hot water supply and the thermistor for hot water supply, which is provided at the outlet of the hot water supply and which detects the hot water temperature and the inlet of the heat exchanger for additional heating, and detects the circulating hot water temperature and the hot water temperature during automatic hot water supply, and the hot water supply thermistor. Water supply detecting element for calculating and measuring the amount of water supply provided in the bathtub automatic hot water supply passage having a hot water supply flow rate control valve connected to the hot water circulation passage and branched from the hot water supply passage downstream of And automatic control of hot water supply Sometimes the control circuit opens the hot water supply flow rate control valve, and operates the proportional control valve to operate the proportional heat control burner by the control signal calculated by the signals of both the hot water supply thermistor and the additional heating thermistor. In addition to controlling the amount of combustion, when the water temperature is low, such as in winter, or by using multiple taps on the hot water supply, the hot water supply capacity is exceeded and the automatic hot water temperature for the bathtub becomes lower than the temperature set above the bath boiling temperature. When it becomes lower than the thermistor for reheating and the difference between the signals of both thermistors becomes large, the solenoid valve for reheating is also opened, and the burner for reheating is simultaneously burned to automatically supply hot water to the bathtub. At the same time, the hot water supply detecting element is configured to close the hot water supply flow rate control valve at an arbitrary set amount to stop automatic hot water supply, and has the following effects.

(1) Since the hot water temperature is controlled by proportionally controlling the combustion amount with one proportional control valve for both hot water supply and additional heating, the hot water temperature can be stabilized.

(2) In particular, since the bath temperature can be controlled in proportion to the bath temperature, energy saving can be achieved as compared with the conventional hot-water control by Hi-Lo-OFF or ON-OFF control.

(3) Since the automatic hot water supply function is built into the main body, the cost can be reduced, the installation can be made free, the workability can be improved, and the aesthetic appearance of the building will not be impaired.

(4) By using the water supply detection element as a water amount sensor that counts the amount of water supplied, it is possible to set the amount of hot water supplied to the bathtub automatically during automatic hot water supply and automatically stop it. No water level sensor that detects the water level in the bathtub is required other than the sensor that detects the water level.

(5) Since automatic hot water supply to the bathtub uses a connection pipe for circulating hot water, there is no need for a hot water supply pipe for automatic hot water supply, and construction costs can be reduced.

(6) Since hot water can be automatically supplied with the lid of the bathtub kept open, there is no need to sprinkle water, energy can be saved, and it is economical.

(7) Bath heating time can be completed only by automatic hot water supply operation without additional heating operation to the desired bath boiling temperature, and does not require additional heating operation after automatic hot water supply as in the past. It becomes shorter and you can enjoy a comfortable bath life economically.

(8) When the water temperature is low, such as in winter, or the use of multiple hot water supply taps exceeds the hot water supply capacity, the automatic hot water temperature to the bathtub becomes lower than the bath boiling temperature set by the bathtub hot water temperature setting device. If the signal difference of the thermistor becomes large, the solenoid valve for reheating is also opened, and the burner for reheating is also burned at the same time to burn with high capacity, so that the bath temperature of the bathtub is increased. Automatic hot water can be supplied to the boiling temperature in a short time.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 2 is a schematic configuration diagram of a control circuit, FIG. 3 is a flowchart of an automatic hot water supply operation program, and FIG. 4 is a configuration of a conventional example. It is a schematic diagram. 1 ... Heat exchanger for hot water supply, 2 ... Heat exchanger for additional heating, 3 ...
Pump, 4 ... Bathtub, 11 ... Original solenoid valve, 12 ... Hot water solenoid valve, 13 ... Proportional control valve, 14 ... Hot water burner, 15 ...
Solenoid valve for reheating, 16 ... Burner for reheating, 17 ... Water supply detecting element, 18 ... Hot water supply thermistor, 19 ... Circulating water detecting element,
20 …… Additional thermistor, 24 …… Hot water supply control valve.

Claims (1)

[Claims] 1. A heat exchanger for reheating a hot water circulation passage, which is connected to a heat exchanger for hot water supply and a bath and circulates hot water by a pump, a proportional control valve connected in series with an original solenoid valve, and each of the heat exchangers. A hot water supply solenoid valve and an additional heating solenoid valve branched and connected from the proportional control valve to each of the desired hot water supply burner and additional heating burner, and a hot water supply heat exchanger provided at the outlet of the hot water supply heat exchanger. Provided at the inlet of the hot water supply thermistor for detecting hot water temperature and the heat exchanger for additional heating, from the hot water thermistor for detecting circulating hot water temperature and hot water supply temperature during automatic hot water supply, and from the hot water supply passage downstream of the hot water supply thermistor. A bathtub automatic hot water supply path having a hot water supply flow rate control valve branched and connected to the hot water circulation passage, a water supply detection element for calculating and measuring the amount of water supply provided in the water supply passage of the heat exchanger for hot water supply, and a control circuit. The control circuit is provided for automatic hot water supply operation. The hot water supply flow rate control valve is opened, and the proportional control valve is operated by the control signal calculated by the signals of both the hot water supply thermistor and the additional heating thermistor to control the combustion amount of the hot water supply burner. At the same time, when the water temperature is low, such as in the winter, or by using multiple taps for the water heater,
When the hot water supply capacity is exceeded, the temperature of the hot water supplied to the bathtub is lower than the bath boiling temperature, the hot water supply thermistor is lower than the reheating thermistor, and the signal difference between the both thermistors becomes large, The solenoid valve for additional heating is also opened to burn the additional burner at the same time to automatically supply hot water to the bathtub, and the water supply detection element closes the hot water supply flow rate control valve at an arbitrary set amount and automatically. A water heater with a reheating function that is configured to stop hot water supply.