JPH0745969B2 - 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. Baths such as added ones are being automatically supplied.

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 a hot water passage extending from the hot water return port 2a to the additional heating heat exchanger 2, and a bathtub 4 is connected between 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 10 so that combustion air can be supplied from the air supply port 9. The fuel passage is branched from the original solenoid valve 11, to the hot water supply burner 14 through the hot water supply solenoid valve 12 and the proportional control valve 13, and to the additional heating burner 16 through the additional heating solenoid valve 15.
Are connected to each. A water supply detection element 17 that detects water supply and outputs a signal is provided in the water supply passage, and a hot water supply thermistor 18 that detects hot water temperature 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 heating, and an additional hot water detecting element for detecting hot water temperature at the inlet of the heat exchanger 2 for heating. A thermistor 20 for heating is provided. The hot water supply 21 is connected to the hot water supply port 1b through the hot water supply pipe 22 to, for example, a bathroom or a kitchen, and the hot water supply control valve 24, the hopper 25, and the water level sensor for the hot water of the bathtub are automatically supplied to the bathtub 4.
An automatic hot water supply unit 23 having 26 is provided branching from the hot water supply pipe 22 and connected to the bathtub 4. The actuator (solenoid valve, pump, etc.) receives a control circuit in response to the signals from the various sensors.
27 and a remote controller 28 to operate.

Next, the operation will be explained. By opening the hot water dispenser 21,
Water flows into the water supply passage, the water supply detection element 17 operates, the main solenoid valve 11, the hot water supply solenoid valve 12 and the proportional control valve 13 open, and the fuel flowing to the hot water supply burner 14 is ignited to ignite the hot water supply thermistor 18. Signal to operate the proportional control valve 13 with the output processed by the control circuit 27 so that the hot water supply temperature becomes the hot water supply temperature set by the hot water supply hot water temperature setting device (not shown) of the remote controller 28, The combustion amount of the hot water supply burner 14 is controlled to stably control the hot water supply hot water temperature.

On the other hand, by operating an additional heating switch (not 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 detecting element 19 which detects this is detected. Operate the original solenoid valve 11, solenoid valve for additional heating
The valve 15 opens to ignite the fuel that has flowed to the additional burner 16. Then, the circulating hot water temperature is sensed and set by the signal from the additional heating thermistor 20 provided at the inlet of the additional heat exchanger 2 and the bath water temperature setting device (not shown) of the remote controller 28. The control circuit 27 is operated so that the bath heating temperature is reached, the solenoid valve 15 for additional heating is operated, the combustion amount of the additional burner 16 is controlled, and the circulating hot water is stably controlled to control the bath water. It is configured to control the 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 by the output processed by the control circuit 27 so that the valve 24 is opened and the automatic hot water temperature is set by the 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, the hot water is automatically supplied to the bathtub 4. Then, in order to cover the decrease in the hot water supply temperature due to the length of the hot water supply pipe 22, the water level sensor 26 operates to close the hot water supply control valve 24 to stop the automatic hot water supply, and then the pump 3
And the control circuit 27 is operated so that the signal from the reheating thermistor 20 and the bath boiling temperature set by the bathtub hot water temperature setting device (not shown) of the remote controller 28 are reached. The solenoid valve 15 for heating is operated to control the combustion amount of the burner 16 for additional heating to stably control the circulating hot water and control the bath water temperature.

Problems to be Solved by the Invention 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 is installed when the bathroom is in the center of the room due to the configuration of the building. However, even if it could be installed on the wall side, there were problems such as a defect in the appearance and aesthetics of the building.

Further, after the automatic hot water supply operation, the additional heating operation is required, and it takes time to reach the bath boiling temperature, which is uneconomical.

In view of the above problems, the present invention intends to provide an automatic hot water supply function which is inexpensive and can be installed freely, which is effective in terms of workability and aesthetics.

Means for Solving the Problems In order to solve the above problems, the water heater with a reheating function of the present invention is a heating water for a hot water circulation passage which is connected to a hot water heat exchanger and a bath and circulates hot water with a pump. An exchanger, a proportional control valve connected in series with the original solenoid valve, and a hot water supply solenoid connected branching from the proportional control valve to each of the hot water supply burner and the additional heating burner desired for each heat exchanger. Valve and solenoid valve for reheating, installed at the outlet of the heat exchanger for hot water supply, installed at the inlet of the thermistor for hot water supply and heat exchanger for heating hot water, for hot water heating for detecting circulating water A thermistor, a hot water supply flow rate control valve provided in a bathtub automatic hot water supply passage branched from a hot water supply passage downstream of the hot water supply thermistor and connected to a bathtub, and a water supply passage of the hot water supply heat exchanger to calculate and measure the amount of water supply. Automatic hot water supply with a water supply detection element and a control circuit During operation, the control circuit opens the hot water supply flow rate control valve, and according to a control signal calculated by the signal of the hot water supply thermistor,
The proportional control valve is operated to control the combustion amount of the hot water supply burner to automatically supply hot water to the bathtub so as to reach the desired hot water supply temperature (desired bath boiling temperature). When the hot water supply flow control valve is closed at an arbitrary set amount to stop the automatic hot water supply in the bathtub, complete the automatic hot water supply operation without the additional heating operation, and when the water temperature is low during the automatic hot water supply in the bathtub, etc. If the signal of the hot water supply thermistor becomes lower than the automatic hot water supply set temperature due to the use of multiple hot water supply plugs, the hot water supply capacity is exceeded, and the specified amount is measured by the signal of the water supply detection element, the control circuit The control circuit is configured to automatically open the hot water to the bath while circulating the hot water by opening the electromagnetic valve for additional heating by the signal to burn the additional burner for burning at the same time and rotating the pump.

With the above-described configuration, the present invention operates the proportional control valve with the output calculated by the control circuit by the signal of the hot water supply thermistor to control the combustion amount of the hot water supply burner and stabilize the hot water supply temperature during the hot water supply operation. It can be controlled. Further, during the heating operation, the proportional control valve is operated by the output processed by the control circuit according to the signal from the heating thermistor to control the combustion amount of the heating burner to stably control the bath water temperature. .

Further, during simultaneous operation of both of the above, the control circuit preferentially operates the proportional control valve with the output calculated in the hot water supply mode to stably control the hot water supply temperature, and the heating side outputs the signal of the heating thermistor. By controlling the opening and closing of the additional heating solenoid valve, the bath water temperature can be controlled stably.

Furthermore, during the automatic hot water supply operation, the hot water supply flow rate control valve is opened to automatically supply hot water from the hot water supply heat exchanger to the bathtub through the bathtub automatic hot water supply passage, and the automatic hot water supply temperature is calculated by the control circuit using the signal from the hot water supply thermistor. The proportional control valve is operated with the generated output to control the combustion amount of the hot water supply burner.
When the water temperature is lower, such as in the winter, or when multiple taps are used for the hot water supply, the signal from the thermistor for hot water supply becomes lower than the set temperature for automatic hot water supply, exceeding the hot water supply capacity, and the amount specified by the signal from the water supply detection element. If the temperature is measured, the temperature of the hot water supplied to the bathtub becomes lower than the bath boiling set temperature, so the solenoid valve for additional heating is also opened to burn the additional heating burner at the same time and the pump also rotates. By automatically supplying hot water to the bathtub while circulating hot water (heating operation), it is possible to automatically supply hot water to the initial bath boiling temperature in a short time. Further, the hot water supply flow rate control valve can be closed at an arbitrary set amount by the signal of the water supply detecting element to stop the automatic hot water supply in the bathtub.

In addition, the number of parts can be reduced, the automatic hot water supply function can be manufactured at low cost, and the installation can be freely performed to improve the workability and aesthetics 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 returning port 2a to the heat exchanger 2 for additional heating, and a bathtub 4 is provided between the hot water returning port 2a and the hot water outgoing port 2b. Are connected by a connecting pipe 5 to form a hot 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 10 so that combustion air can be supplied from the air supply port 9. The fuel passage connects the original solenoid valve 11 and the proportional control valve 13 in series, and branches from this 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,
A branch connection is made so that the proportional control valves 13 are commonly connected.

Next, the signal of the hot water supply thermistor 18 provided at the outlet of the hot water supply heat exchanger 1 shown in the schematic control circuit configuration of FIG. 2 and the hot water supply temperature set by the hot water supply temperature setting device 31 of the remote controller 28 are set. Further, the comparator 32 of the control circuit 27 performs a comparison calculation, and the proportional control valve drive unit 34 is operated by the output processed by the calculation processing unit 33 to operate the proportional control valve 13 and the hot water supply burner 14
The hot water supply operation control unit 38 is configured so as to control the combustion amount of the hot water to stably control the hot water temperature.

On the other hand, the control circuit 27 is compared so that the signal from the additional heating thermistor 20 provided at the inlet of the additional heating heat exchanger 2 and the bath boiling temperature set by the bathtub hot water temperature setting device 35 of the remote controller 28 are brought to the same level. Comparing calculation in the device 36, operating the proportional control valve drive unit 34 by operating the proportional control valve drive unit 34 with the output processed by the arithmetic processing unit 33, and controls the combustion amount of the additional heating burner 16, The circulating hot water is stably controlled 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 combustion amount of the additional heating burner 16 controlled by up to the bath boiling temperature set by the bath water temperature setting device 35, when the boiling temperature is reached by controlling the maximum capacity without proportional control, the The control circuit so as to close the solenoid valve 15 for additional heating
The additional heating control unit 37 of 27 is configured.

The hot-water supply solenoid valve 12 and the hot-water supply solenoid valve 15 are configured with a hot-water supply operation control unit 37 and a hot-water supply operation control unit 38 so as to open and close when controlling the hot water temperature. In the simultaneous operation, the hot water supply operation control unit 38 of the control circuit 27 preferentially operates the proportional control valve drive unit 34 by operating the proportional control valve drive unit 34 with the output processed by the arithmetic processing unit 33 in the hot water supply mode. While controlling the hot water supply hot water temperature stably, the reheating side controls the opening and closing of the reheating solenoid valve 15 by the signal of the reheating thermistor 20, so that the bath water temperature can be controlled stably. Operation control unit
37 are configured.

Furthermore, during the automatic hot water supply operation, the hot water supply flow rate control valve 24 and safety valve
29 (vacuum breaker) is provided so as to be branched from the hot water supply passage downstream of the hot water supply thermistor 18 and connected to the bathtub 4 through the bathtub automatic hot water supply passage 30. Then, the hot water supply flow rate control valve 24 is opened by a signal from the hot water supply operation control unit 38 to pass through the hot water supply heat exchanger 1, and the signal from the hot water supply thermistor 18 causes the comparator 32 of the control circuit 27 to operate. And 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
Is operated to control the combustion amount of the hot-water supply burner 14 to stably control the hot-water supply hot water temperature and automatically supply hot water to the bathtub 4.

Also, when the water temperature is low, such as in the winter, or the use of multiple hot water supply taps exceeds the hot water supply capacity, the signal from the hot water supply thermistor 18 becomes lower than the set temperature for automatic hot water supply, and there is a large deviation from the desired bath boiling temperature. In the case where the above is compared and calculated by the comparator 32, and the signal of the water supply detection element 17 for calculating and measuring the water supply amount provided in the water supply passage is supplied by the hot water supply operation control unit 38 to the specified amount (for example, 1/3 of the bathtub 4). About 1/2 of the amount of water
80 to 100 l) is measured, the pump 3 is also rotated to circulate warm water, and the operation of the circulating water detection element 19 causes the operation of the additional heating operation control section 37 to open the additional heating solenoid valve 15 as well. As a result, the hot-burner 16 is automatically burned while the hot-burner 16 is automatically burnt. Then, by measuring the signal of the water supply detecting element 17, the hot water supply flow rate control valve 24 is closed at an arbitrary set amount to automatically and automatically supply hot water to the desired bath boiling temperature in a short time. The hot water supply operation control unit 38 is configured to stop hot water supply.

The operation of the above embodiment will be described.

I, Hot water supply operation When the hot water supply pipe 21 connected to the hot water supply port 1b is used to open a hot water supply pipe 21 in a bathroom or kitchen, for example, the water supply detecting element 17 detects the water supply and the hot water supply operation sequence is operated. The portion 38 is configured and the exhaust fan 7 rotates. The original solenoid valve 11, the hot water solenoid valve 12, and the proportional control valve 13 are opened, and the fuel is ignited and held. (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 with the output calculated in step S1 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 supply temperature.

II, Reheating Operation On the other hand, the pump 3 and the exhaust fan 7 are rotated by operating a reheating operation switch (not shown) provided on the remote controller 28. Then, when hot water or water stored in advance in the bathtub 4 is circulated by the pump 3, the circulating water detection element 19 detects the hot water or water and the reheating operation control unit 37 is configured to operate the reheating operation sequence. The original solenoid valve 11, the additional solenoid valve 15,
The proportional control valve 13 is opened to keep the fuel ignited. (Ignition holding means is not shown in particular) Then, as the reburning burner 15 burns, the reheating heat exchanger 2 is heated to circulate in the bathtub 4 from the hot water outlet port 2b through the connecting pipe 5 to generate hot water. Hot water is circulated through the return port 2a. The comparator 36 of the control circuit 27 compares the circulating hot water equal to the hot water in the bathtub 4 so that the bath heating temperature set by the signal of the thermistor 20 for additional heating and the bathtub hot water temperature setting device 35 of the remote controller 28 will be reached. Calculation, 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. Control the 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 heating operation control unit 37 controls so that the heating solenoid valve 15 is closed.

III, automatic hot water supply operation When the automatic hot water supply operation switch provided on the remote controller 28 is operated, the hot water supply flow control valve 24 is opened, and hot water is automatically supplied to the bathtub 4 through the hot water supply heat exchanger 1 and the bathtub automatic hot water supply passage 30. It The hot water supply operation control unit 38 is configured so that the water supply detecting element 17 detects the supplied water and operates the automatic hot water supply motion sequence, and the exhaust fan 7 rotates. The original solenoid valve 11, the hot water solenoid valve 12, and the proportional control valve 13 are opened, and the fuel is ignited and held. (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 automatically supplied to the bathtub 4 through the hot water supply flow rate control valve 24 and the bathtub automatic hot water supply passage 30. . The hot water supply temperature is detected by the hot water supply thermistor 18, and the automatic hot water supply hot water temperature setting device of the remote controller 28 is detected.
Hot water supply temperature set at 31 '(desired bath boiling temperature)
The comparator 32 of the control circuit 27 performs the comparison calculation so that the proportional control valve drive unit 34 outputs the output processed by the calculation processing unit 33.
Is operated 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 supply temperature and automatically supply hot water to the bathtub 4.

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.

Simultaneous operation of IV, automatic hot water supply and reheating In addition, when the water temperature is low such as in winter or by using multiple taps of the hot water supply, the hot water supply capacity is exceeded and the signal of the hot water supply thermistor 18 becomes lower than the automatic hot water set temperature, When the comparator 32 performs a comparison calculation that the deviation is larger than the desired bath boiling temperature, and specifies the signal of the water supply detection element 17 for calculating and measuring the water supply amount provided in the water supply passage by the hot water supply operation control unit 38. Amount (for example, about 1/3 to 1/2 the amount of water in bath 4
80 to 100 l) is measured, the pump 3 is also rotated to circulate warm water, and the operation of the circulating water detection element 19 causes the operation of the additional heating operation control section 37 to open the additional heating solenoid valve 15 as well. The hot water heating burner 16 is also burned at the same time to automatically supply hot water to the bathtub 4 while operating the hot water, and by measuring the signal from the water supply detecting element 17, the hot water supply flow control valve 24 is set at an arbitrary set amount. By closing the valve, the bath water temperature can be automatically stopped and stopped at 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 detection element 17, so it detects the amount of ignition / extinguishing water and controls the amount of hot water supplied by the control circuit 27 during automatic hot water supply operation. The hot water supply flow control valve 24 can be automatically closed by calculating and measuring in the section 38 to stop the automatic hot water supply. The safety valve (vacuum breaker) 29 is provided to prevent backflow into the hot water supply passage due to the rotation of the pump 3 during the additional heating operation.

Further, 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 detecting element 17 is measured in step 42, and when the amount of ignition water is detected, the automatic hot water supply operation in step 43 operates and the hot water supply burner 14
Is burned and hot water is automatically supplied. The hot water supply temperature is detected by the hot water supply thermistor 18, and a comparison calculation is performed by the automatic hot water supply hot water temperature setting device 31 'and the comparator 32, and it is determined in step 44 whether or not it is equal to or higher than the hot water supply capacity.

Normally, it is controlled within the hot water supply capacity range.
The hot water supply temperature is controlled by the automatic hot water supply set temperature by 46, and the hot water is automatically supplied. When the automatic hot water supply amount in step 47 reaches the set amount, the hot water supply flow rate control valve 24 is closed in step 48, automatic hot water supply is stopped, and the hot water is set to the desired hot water supply set temperature (bath boiling temperature) in the bathtub 4 No automatic hot water supply operation is completed.

On the other hand, when the water temperature is low such as in winter or when using multiple taps of the hot water supply, the hot water supply temperature is detected by the thermistor 18 for hot water supply, and the automatic hot water supply temperature setter 31 'and the comparator 32 perform a comparison calculation,
If it is determined in step 44 that the hot water supply capacity or more is determined, the automatic hot water supply amount is measured in the specified amount in step 49 (for example, 80 to 100 liters), and the hot water supply / additional heating simultaneous operation sequence in step 50 is performed, and the additional heating burner 16 also At the same time, the hot water is circulated to the bathtub 4 by the combustion, and the signal from the thermistor 20 for additional heating causes the step 51
By controlling the bathtub hot water temperature by 52 and 52, the bathtub hot water temperature is controlled in a stable manner while automatically supplying hot water so as to reach the bath boiling set temperature.

In this case, the set temperature above the bath is 3
The signals of the comparators 32 and 36 are controlled and operated by the arithmetic processing unit 33 so as to be equal to the set temperature of 1 '.

When the amount of automatic hot water supply reaches the set amount in step 53, step
At 54, the hot water supply flow rate control valve 24 is closed to stop the automatic hot water supply to the bathtub and bring the bathtub hot water temperature to the desired bath boiling temperature.

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. Is provided at the outlet of the hot water supply thermistor for detecting the hot water temperature and the inlet of the heat exchanger for additional heating, and the thermistor for hot water detection for detecting the circulating hot water and the hot water supply passage downstream of the hot water supply thermistor. A hot water supply flow rate control valve provided in a bathtub automatic hot water supply passage connected to the bathtub, and a water supply passage of the hot water supply heat exchanger,
A water supply detection element for calculating and measuring the amount of water supply and a control circuit are provided, and during automatic hot water supply operation, the control circuit opens the hot water supply flow rate control valve, and a control signal calculated by the signal of the hot water supply thermistor is used, The proportional control valve is operated to control the combustion amount of the hot water supply burner to automatically supply hot water to the bathtub so as to reach the desired hot water temperature (desired bath boiling temperature). The flow control valve is closed at an arbitrary set amount to stop the automatic hot water supply in the bathtub and complete the automatic hot water supply operation without the additional heating operation. If the signal of the hot water supply thermistor becomes lower than the automatic hot water supply set temperature due to the use of multiple taps of the hot water, exceeds the hot water supply capacity, and if the specified amount is measured by the signal of the water supply detection element, The control circuit is configured to automatically supply hot water to the bath while circulating the hot water burner and burning the hot air burner at the same time by rotating the pump to rotate the hot water by the signal from the control circuit. It has the following effect.

(1) The hot water temperature can be stabilized because 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.

(2) Especially, since the bath water temperature can be controlled proportionally,
Energy saving can be achieved compared to the conventional hot water temperature control by Hi-Lo-OFF or ON-OFF control.

(3) Since the automatic hot water supply function can be built into the main body, it is possible to reduce the cost and make installation free to improve the workability, and not to impair the aesthetics of the building.

(4) By using a water amount sensor that counts the amount of water supplied as the water supply detection element, 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 volume.

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

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

(7) When the water temperature is low, such as during the winter season, or when the hot water supply is overloaded and the hot water supply thermistor's signal becomes lower than the automatic hot water supply set temperature and the deviation from the desired bath boiling temperature is large. In addition, when the specified amount (for example, about 80 to 100 l which is 1/3 to 1/2 of the water volume of the bathtub 4) is measured by the water supply detection element that calculates and measures the water supply amount provided in the water supply passage, The pump is also rotated to circulate hot water, and the solenoid valve for heating is opened by the operation of the circulating water detection element to burn the heating burner at the same time, and the hot water is automatically supplied to the bath while the heating operation is being performed. By closing the hot water supply flow rate control valve at an arbitrary set amount, the bath water temperature can be automatically and automatically stopped in a short time up to the desired bath boiling temperature, which shortens the bath boiling time. Economically comfortable, Lu of life can be.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a water heater with an additional heating function showing an embodiment of the present invention, second 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 conventional example. FIG. 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 heating thermistor, 24 …… hot water supply flow control valve, 27…
… Control circuit (control section), 30… Bathtub automatic hot water supply passage.

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. A hot water thermistor for detecting the hot water temperature and an additional heat thermistor for detecting the circulating hot water provided at the entrance of the heat exchanger for additional heating,
A hot water supply flow rate control valve provided in a hot water supply passage for a bathtub that branches from a hot water supply passage downstream of the hot water supply thermistor and connected to a bathtub, and a water supply detection for calculating and measuring the amount of water supply provided in the water supply passage of the hot water supply heat exchanger An element and a control circuit, the control circuit opens the hot water supply flow rate control valve during an automatic hot water supply operation, and operates the proportional control valve according to a control signal arithmetically processed by the signal of the hot water supply thermistor, Control the combustion amount of the hot water supply burner to automatically supply hot water to the bathtub to reach the desired hot water temperature (desired bath boiling temperature), and set the hot water supply flow control valve to an arbitrary set amount by the signal from the water supply detection element. To stop the automatic hot water supply in the bathtub and complete the operation only with the automatic hot water supply without additional heating, and
When the bath water temperature is low during the hot water supply in the bathtub, such as during the winter season, or when multiple taps are used for the hot water supply, the signal from the thermistor for hot water supply becomes lower than the set temperature for automatic hot water supply. When is measured, the solenoid valve for reheating is opened by the signal of the control circuit, the burner for reheating is simultaneously burned, the pump is also rotated, and hot water is automatically supplied to the bath while circulating hot water. A water heater with a reheating function that is configured by the control circuit described above.