JP2002115904A - Hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water supply system suppressing power consumption during the standby of operation greatly and capable of the reset of operation optionally. SOLUTION: Remote control systems (104 and 106) are fed from the control device (100) on a hot water supply apparatus (a hot water supplying and reheating device 2) side through telecommunication cables (102, a positive electrode side cable 146 and a negative electrode side cable 148), and a hot water supply system is provided with a power supply switching means (a switch circuit 134) for changing over the feed to the remote control system, an input means (a reset switch 242) for inputting the power supply switching command and a controlling means (a control device 100) for changing over the feed to the remote control system on the basis of the switching command. Changing over the feed to the remote control system side reduces power consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply system used for hot water supply or filling a bathtub.

[0002]

2. Description of the Related Art In an automatic hot water supply system, the standby power of a water heater is consumed by a remote control device, a control board, a fan motor, and the like. Measures such as reducing the current, stopping the energization of the control circuit of the fan motor, and reducing the loss of the transformer have been taken to reduce the power consumption. This hot water supply system is provided with a remote control device for instructing hot water supply or hot water filling in a bathtub, and a display device such as a fluorescent display tube, a liquid crystal display, and an LED for displaying desired information and instruction contents. Is provided. This remote control device is supplied with drive power from the hot water supply device side, and the power supply is maintained even during the operation standby, so that the power consumption cannot be ignored.

[0003]

By the way, when the power supply to the remote control device is stopped, power consumption can be completely eliminated. However, since the power supply is supplied from the control circuit, the power supply is restored from the remote control device side. It is impossible to maintain the CPU serving as the control means in the operation standby state. For this reason, there is a limit to the reduction of power consumption during operation standby, and reduction of power consumption is demanded.

[0004] Therefore, an object of the present invention is to provide a hot water supply system that can greatly reduce power consumption during operation standby and can arbitrarily return to operation.

[0005]

A hot water supply system according to the present invention comprises a remote control device (104, 106) having a hot water supply (hot water supply / hot water supply).
The communication cable (102, the positive-side cable 146, the negative-side cable 14)
8) and power supply switching means (switch circuit 13) for switching power supply to the remote control device.
4), input means (return switch 242) for inputting a power supply switching command, and control means (control device 100) for switching power supply to the remote control device based on the switching command, and by switching power supply to the remote control device side, Power consumption is reduced.

[0006] The hot water supply system of the present invention according to claim 1 comprises:
A control device (100) on the side of the water heater (hot water supply / reheating device 2) and a remote control device (104, 106) are provided, and the remote control device is provided with a communication cable (102, a positive electrode cable 146, a negative electrode cable) from the control device. 148), a power supply switching means (switch circuit 134) for switching the form of power supply to the remote control device between normal power supply and standby power supply such as low-voltage power supply, and normal power supply to the remote control device side. An input unit (return switch 242) for inputting a switching command between power supply and standby power supply, and controlling the power supply switching unit based on the switching command of the input unit to change the power supply mode to the remote control device to the normal power supply or the standby mode Control means for switching to power supply (control device 10
0).

That is, power is supplied from the control device to the remote control device through the power supply switching means, and there are two types of power supply: normal power supply and standby power supply. The standby power supply includes low-voltage power supply, and the low-voltage power supply is power supply with a low voltage at which the remote controller stops operating.

[0008] When the power supply mode is switched through the input means and the normal power supply is changed to the standby power supply, the power consumption of the remote controller is suppressed. Further, during standby power supply, when a power supply mode switching command is input from the input unit, power supply to the remote controller is switched from standby power supply to normal power supply. A desired operation is performed in this state.

The hot water supply system of the present invention according to claim 2 is
A switch (return switch 242) is provided as the input means, and a voltage detection means (voltage detection circuit 140) for detecting a voltage change caused by operation of the switch during the standby power supply is provided. The power supply is switched to the remote controller based on That is, at the time of standby power supply, power is supplied from the control device to the remote control device at a low voltage. A voltage change occurs. This is detected by the voltage detecting means, and the power supply to the remote controller is switched to the normal power supply based on the voltage change detection.

The hot water supply system of the present invention according to claim 3 is
When shifting to the standby power supply, the control information stored in the storage unit on the remote control device is transferred to the storage unit on the control device immediately before the standby power supply. That is, since the remote control device in the operation standby state shifts to the standby power supply, the control information of the storage means may be lost. Therefore, when shifting to standby power supply, the stored information immediately before that is transferred to the storage means on the control device side, thereby preventing the loss of the control information. Thereby, the continuity of the control is maintained, and the reliability of the control is ensured.

[0011] A hot water supply system according to a fourth aspect of the present invention comprises:
When shifting to the normal power supply, the control information stored in the control device is transferred to a storage unit in the remote control device. That is, since it is expected that the control information in the storage means on the remote control device side will be lost due to standby power supply, the control continuity of the control is maintained by transferring the control information in the storage means on the control device side to the remote control device. Thus, control reliability is ensured.

[0012] The hot water supply system of the present invention according to claim 5 is as follows.
When a predetermined time has elapsed since the start of the normal power supply, the power supply to the remote controller is switched to the standby power supply. That is, since the power supply switching by the input means is left to the user's intention, the power supply can be mechanically switched to the standby power supply after a lapse of a predetermined time from the start of the normal power supply, and the power consumption can be suppressed.

Further, the hot water supply system of the present invention according to claim 6 is characterized in that power supply to the remote control device is switched based on detection of flowing water in a heat exchanger of the water heater. That is, when running water is generated in the heat exchanger,
Since the heating device such as a burner shifts to the operating state, the remote control device shifts from the standby state to the operating state to realize a necessary operation.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to embodiments shown in the drawings.

FIG. 1 shows the overall configuration of a hot water supply / reheating system which is an embodiment of the hot water supply system of the present invention. The hot water / reheating unit 2 is provided in the hot water / reheating unit, and the hot water / reheating unit 2 includes a heat exchanger 4 for heating hot water and a heat exchange for reheating for heating water in a bathtub. A water supply W is supplied to the heat exchanger 4 through a water supply port 8 and a water supply pipe 10, and hot water HW obtained by the heat exchanger 4 is supplied through a hot water supply port 12 and a hot water supply pipe 14 to a kitchen, a shower, or the like. It is supplied to hot water tap 16. Further, the water BW in the bathtub 28 circulates through the heat exchanger 6 via the additional heating ports 18 and 20, the return pipe 22, the going pipe 24, and the circulation connector 26. That is,
Between the heat exchanger 6 and the bathtub 28, there is formed a circulation pipe composed of the return pipe 22, the going pipe 24 and the like. Further, since the hot water supply pipe 30 branched from the hot water supply pipe 14 is connected to the outgoing pipe 24 via the switching valve 32, the hot water H as the clean water is supplied.
W is supplied to the bathtub 28 through the going pipe 24.

The heat exchangers 4 and 6 are provided with burners 34 and 36 as heating means, and the burner 36 is provided with a fuel supply pipe 40 and a burner 34 through a fuel supply port 38.
Are connected to fuel supply pipes 42 branched from the fuel supply pipes 40, respectively, and the fuel gas G is supplied individually. An on-off valve 44 as switching means for supplying and shutting off the fuel gas G to the fuel supply pipe 40, an on-off valve 46 as switching means for supplying fuel to the burner 36, and a fuel adjusting means for the fuel supply pipe 42. A fuel proportional valve 48 is provided.
The fuel proportional valve 48 is a valve whose opening can be adjusted, and the combustion amount of the burner 34 can be controlled by the supply amount of the fuel gas G. Each of the burners 34 and 36 has a spark plug 5 as a means for igniting the fuel gas G in the vicinity of its combustion surface.
0 and 52 are provided.

The water supply pipe 10 has a water supply temperature sensor 54 for detecting the temperature of the clean water W, and a water supply amount sensor 5 for detecting the inflow amount.
6. Hot water temperature sensor 58 for detecting hot water temperature of heat exchanger 4
The detected tap water temperature, water supply amount, and tap water temperature are used for calculating an optimal fuel supply amount for maintaining the tap water at the set temperature, and the optimal control of the fuel proportional valve 48 is realized. You. The opening of the hot water tap 16 or the like is a hot water supply request to the hot water / reheating unit 2, and the degree of the opening, that is, the amount of flowing water is detected by the water supply amount sensor 56. Further, the hot water supply pipe 30 has an opening / closing valve 60, a hopper for separating the bathtub 28 from the hot water HW, and a rimping device 6 such as a vacuum breaker.
2. A water amount sensor 64 for detecting the amount of hot water supplied to the bathtub 28 is provided. When the on-off valve 60 is opened, the hot water HW obtained in the heat exchanger 4 is supplied to the bathtub 28 side, and the bathtub 28 is filled with hot water. The return pipe 22 has a temperature sensor 66 for detecting the temperature of hot water in the bathtub 28, a water level sensor 68 for detecting the water level in the bathtub 28, and a pump 7 for circulating hot water in the bathtub 28.
0, a running water sensor 72 for detecting running water generated by the pump 70 is provided.

The hot water supply / reheating unit 2 receives information from various sensors such as the feed water temperature sensor 54 and controls various driving devices such as the fuel proportional valve 48 as a control unit 1.
00 is provided. The control device 100 is connected to a plurality of remote control devices 10 via a two-core communication cable 102.
4 and 106 are connected to each other,
6 is supplied with drive power as well as control information from the control device 100 via the communication cable 102. The control information includes
Includes various information such as combustion control data, operation information, operation commands, tapping temperature, failure information, water level, filling temperature, and the like. The control device 100 includes remote control devices 104, 10
From 6, various setting information such as a set temperature and a set water level, a hot water filling command, and other operation commands are transmitted.

FIG. 2 shows a specific embodiment of the control device 100. The control device 100 includes a control operation unit 110 as control means for performing other control operations of the combustion control.
The control calculation unit 110 includes a CPU 112 for performing control and calculation control necessary for the control, a RAM 114 for temporarily storing calculation data and other data, a CPU 1
ROM 1 storing 12 operation programs and control data
16. EEPROM 118 which is a non-volatile memory which stores control data and protects from power interruption, TIMER 120 for measuring time, input circuit 122, output circuit 12
4, a relay circuit 126, a safety control circuit 128, and the like.

The input circuit 122 receives detection outputs from a water supply temperature sensor 54, a water supply amount sensor 56, a tap water temperature sensor 58, a water amount sensor 64, a temperature sensor 66, a water level sensor 68, and the like. Output is fuel proportional valve 4
8 and a fan motor (not shown) and the like.
6. It is added to driving devices such as the switching valve 32, the spark plugs 50 and 52, and the pump 70. Further, to the safety control circuit 128, detection outputs of an HL switch (not shown), a thermocouple, a flame detector and the like are added.

A commercial power supply is used as a drive power supply for the control device 100. The commercial AC voltage is applied to a rectifier / smoothing circuit 130 to be converted into a DC voltage, applied to a power supply circuit 132, and a switch circuit. It is added to the remote control power supply circuit 136 via 134. The power supply circuit 132 is a means for supplying a voltage required for operation to circuits such as the control operation unit 110, sensors, driving equipment, and the like. Have been. Low voltage power supply circuit 1
The output of 38 is applied to a voltage detection circuit 140. Further, the remote control power supply circuit 136 and the low voltage power supply circuit 138
The output of is a backflow prevention circuit 142 and a high frequency prevention circuit 144.
Via the communication cable 102 on the positive cable 146 side. The output voltage of the low-voltage power supply circuit 138 is used to restore the power supply to the remote control devices 104 and 106,
That is, it is used for switching from standby power supply (for example, power supply of 1 V or less) to normal power supply (for example, power supply of about 15 V). The backflow prevention circuit 142 is provided by the remote control power supply circuit 1.
The output of the low voltage power supply circuit 138 is prevented from being applied to the low voltage power supply circuit 138, and the output of the low voltage power supply circuit 138 is prevented from being applied to the remote control power supply circuit 136 side.

In the communication cable 102, a potential difference generated between the positive cable 146 and the negative cable 148 is equal to the operating voltage of the remote controllers 104 and 106. The output voltage of the low-voltage power supply circuit 138 is applied to the positive cable 146 of the communication cable 102 via the backflow prevention circuit 142 and the high-frequency prevention circuit 144.
The high-frequency blocking circuit 144 is a means for maintaining the high-frequency signal level in the communication cable 102 at a predetermined value. The high-frequency blocking circuit 144 prevents attenuation of the high-frequency signal due to outflow to circuits other than the two-core transmission / reception circuit 139, and maintains the high-frequency signal level. Means.

In such a configuration, the switch circuit 1
When the power supply 34 is operated, power supply to the remote control power supply circuit 136, that is, normal power supply is started, and the transition to standby power supply is automatically switched by the backflow prevention circuit 142. That is, this power supply switching is performed by the remote control power supply circuit 136 which is a normal power supply.
Is to supply power from the low-voltage power supply circuit 138 to the power supply from

By the way, at the time of normal power supply, that is, when the switch circuit 134 is in a conductive state, a voltage of, for example, 15 V is reduced by the high-frequency blocking circuit 144 by the backflow prevention circuit 142 (for example, the OR circuit of the diodes 301 and 318 in FIG. 4). Is supplied to the communication cable 102. At this time, the backflow prevention circuit 142 (for example, the diode 318 in FIG. 4) is turned off.

When the conduction of the switch circuit 134 is released, the supplied voltage 15V shifts to the voltage 0V. At this time, for example, about 1
Since the voltage of V is supplied, the backflow prevention circuit 142
(For example, the diode 318 in FIG. 4) becomes conductive, and a voltage of 1 V or less is automatically supplied to the communication cable 102. That is, the low-voltage power supply circuit 138
For example, even when a voltage of about 1 V is normally output, the backflow prevention circuit 142 (for example, the diode 301 in FIG. 4) is turned off, and no current flows.

As described above, by the switching operation of the switch circuit 134, whether the driving power, which is the normal power supply of the remote controllers 104 and 106, is supplied through the communication cable 102,
As a standby power supply, a low voltage power supply, that is, a low voltage for detecting a return request is applied.

The two-core transmission / reception circuit 139 is connected to the communication cable 102 via a DC blocking circuit 150, and the DC blocking circuit 150 detects only a high-frequency signal superimposed on the communication cable 102. Communication cable 10
2 are connected to the remote control devices 104 and 1 via connection terminals 152 and 154, respectively.
06.

Next, FIG.
A specific example of the sixth side is shown. For example, the remote control device 104 includes a CPU 202 that performs control calculations such as various setting inputs, command input recognition, display, and communication, a RAM 204 that temporarily stores calculation data, setting data, and information from the control device, a control program, and control data. ROM 206 that stores data, etc., and EEPROM that temporarily saves setting data and control data to protect against data erasure such as power failure
208 are provided. An operation circuit 210 is connected to the CPU 202. The operation circuit 210 includes, for example, a hot water switch 212 and a temperature setting switch 21.
4. It is composed of a water level setting switch 216 and the like. Further, a display circuit 218 is connected to the CPU 202, and an output of the display circuit 218 is applied to a display 220 to perform necessary display.

The link between the remote controller 104 and the controller 100 is performed through the communication cable 102, and the positive cable 146,
The negative cable 148 is connected to the depolarization circuit 226 via the connection terminals 222 and 224. In the depolarization circuit 226, the cables 146 and 148 are connected to the connection terminals 222 and 224 in opposite polarities. Also in this case, it is a means for changing to an appropriate polarity voltage to be added to each circuit of the remote control device 104, and is constituted by a diode bridge. The power supplied from each of the cables 146 and 148 is supplied to the power supply circuit 230 via the high-frequency blocking circuit 228 and is also applied to the two-core transmitting / receiving circuit 234 via the DC blocking circuit 232. The power supply circuit 230 is CP
A power supply unit that supplies necessary power to the U202, the display circuit 218, the two-core transmission / reception circuit 234, and the like. The high-frequency blocking circuit 228 is means for maintaining the high-frequency signal transmitted from the two-core transmission / reception circuit 139 at a predetermined signal level.

A small current generating circuit 236 is connected between the cables 146 and 148 as means for generating a small current, and the small current generating circuit 236 is provided with a start button 238 as a starting means. The operation switch 240 and the return switch 242 are operated by 238. The low voltage applied between the cables 146 and 148 causes a small current to flow when the return switch 242 is operated, causing a voltage drop in the small current generating circuit 236. This voltage drop is detected by the voltage detection circuit 140 of the control device 100,
As a control operation of the control device 100, upon receiving this detection output, the power of the remote control device 104 is restored, that is, switching from standby power supply to normal power supply is performed. This return switch 242
Can be constituted by a double switch that operates in conjunction with the operation switch 240, the operation switch 240 can give a power supply switching command to the CPU 202 of the remote control device 104, and the return switch 242 can operate the control device 1.
It is possible to instruct the 00 side to return the power supply.

FIG. 4 shows a specific embodiment of the control device 100 and the remote control devices 104 and 106.
The remote control power supply circuit 136 is rectified and switched via a switch circuit 134 including a transistor 296 and a resistor 298.
The output of the smoothing circuit 130 is added, and the output of the remote control power supply circuit 136 is applied to the positive cable 146 via the diode 301 constituting the backflow prevention circuit 142.
By the operation of 4, the normal power supply, that is, the driving power required for the operation is supplied. The voltage V obtained by the power supply circuit 132
_CC is supplied to the low-voltage power supply circuit 138. In this low-voltage power supply circuit 138, the voltage V _CC is divided by a resistor 306 and diodes 308 and 310,
8, 310, a forward voltage 2V _D is generated. This voltage 2V _D is divided by resistors 312 and 314, which are voltage dividing circuits.
A voltage V _S higher than the forward voltage V _{D of} This voltage V _S, the resistance 316 is a current limiting means, a diode 318 that constitute the backflow prevention circuit 142 is applied to the cable 146 through the high-frequency coil 320 constituting the high-frequency blocking circuit 144. Voltage V _S is dropped by the forward voltage V _D of the diode 318, i.e., V _S -V _D = V _L by the voltage V _L is applied to the cable 146. This voltage V
_L is smaller than the forward voltage V _D of the diode and is a voltage for standby power supply, and is a voltage for detecting a power return request from the remote control devices 104 and 106. Voltage detection circuit 1
Reference numeral 40 denotes a comparator circuit composed of an operational amplifier 300. The comparator circuit 40 compares a voltage _VL obtained by voltage division of the resistors 322 and 324, which are voltage divider circuits, with a voltage of the cable 146, and compares the voltage _VL with the voltage of the remote controller 104, 106. Is detected. The two-core transmission / reception circuit 139 includes a capacitor 326
14 via a DC blocking circuit 150 composed of
6 is connected.

That is, when the switch circuit 134 is in a conductive state, the diodes 301 and 318 constitute an OR circuit, and the diodes necessary for driving the remote controller 104 or 106 are connected.
A voltage of about V is supplied to the communication cable 102 via the high frequency coil 320. At this time, the diode 318 is turned off.

When the conduction of the switch circuit 134 is released, the supplied voltage of 15V shifts to 0V. At this time, for example, about 1
A voltage of V is supplied, the diode 318 becomes conductive, and the power supply to the communication cable 102 becomes a voltage of 1 V or less. That is, even when the low-voltage power supply circuit 138 outputs a voltage of, for example, about 1 V, the diode 301 is turned off and no current flows.

The depolarizing circuit 226 includes the diode 32
8, 330, 332, 334. Connect each cable 146, 148 to connection terminal 2
22 and 224, the diode 32
8, 330, 332, and 334, the polarity is corrected according to the direction of conduction, and output is performed. That is, a positive voltage is output at point a, and a negative voltage is output at point b. Since the voltage V _L for return request detection is lower than the forward voltage V _D of the diode, nonpolar circuit 2
26 cannot be exceeded. Therefore, when power supply is stopped, power consumption in the remote control devices 104 and 106 does not occur. A two-core transmitting / receiving circuit 234 is connected to a point a of the depolarizing circuit 226 via a capacitor 336 of the DC blocking circuit 232, and the high frequency blocking circuit 22
The power supply circuit 230 is connected via the eight high-frequency coils 338.

A resistor 340 and a return switch 242 constituting the small current generating circuit 236 are connected between the connection terminals 222 and 224. When the return switch 242 is turned on, a current flows between the cables 146 and 148 via the resistor 340, and a potential difference between the cables 146 and 148, that is, a voltage between the cables drops. This voltage drop is detected by the voltage detection circuit 140, and the control device 100 detects a power return request from the remote control devices 104 and 106. A high resistance is used for the resistor 340 in order to suppress the amount of voltage drop between the cables 146 and 148. As a result,
When the drive power of the remote control devices 104 and 106 is supplied, the remote control devices 104 and 106 can operate normally even if the return switch 242 is input.
The return switch 242 and the operation switch 240 are composed of two switches that operate in conjunction with each other.
Is given to the CPU 202.

The operation of the hot water supply system having the above configuration will be described with reference to an operation flowchart shown in FIG.

In step S1, remote control device 104,
It is determined whether or not the input from the operation switch 240, that is, the return switch 242 has been detected when the power supply to the power supply 106 is stopped. When the return switch 242 is operated, a current flows through the resistor 340 as its input, and the voltage _VL applied to the communication cable 102 drops. This voltage drop is detected on the control device 100 side, and as a result, the return switch 242
Is detected. When the standby power supply is released by this input, the process proceeds to step S3, and when the input is not detected, the process proceeds to step S2.

In step S2, it is determined whether the hot water tap 16 is opened and a hot water supply request is made. That is, when flowing water is detected by the water supply amount sensor 56, the process proceeds to step S3. If running water is not detected, step S1 is executed.
Move to

In step S3, the low-voltage power supply circuit 1
38, the switch circuit 134 is operated, and the remote control power supply circuit 136 and the two-core transmission / reception circuit 139 are provided.
Start supplying power to. The remote controllers 104 and 106 obtain drive power, the CPU 202 starts operating, and the
4 is checked. After confirming that the setting data and control data have been erased, the two-core transmission / reception circuit 234 is operated to request the control device 100 to transfer the setting data and control data. The control device 100 includes a RAM 11
4 or the control data stored in the EEPROM 118 to the remote controller 104 or 106 via the two-core transmission / reception circuit 139. In this case, RAM2
Various data that is control information may be transferred without performing the memory check of step 04.

In step S4, it is determined whether or not control operations such as hot water supply and reheating are performed by opening the hot water tap 16 or inputting the hot water switch 212 or the like. If a control operation such as hot water supply or reheating is being performed, the process proceeds to step S5 and TIM
When the operation of the ER 120 is cleared, and when control operations such as hot water supply and additional heating are not being performed, that is, when the return switch 242 is turned on, the process proceeds to step S6 to operate the TIMER 120 to start time measurement. In step S7, it is determined whether a predetermined time has elapsed since the start of the time measurement. When the predetermined time has elapsed, the process proceeds to step S9. If the predetermined time has not elapsed, the process proceeds to step S8, in which an operation stop command is input by the operation switch 240,
That is, it is determined whether or not a power supply switching command to remote control device 104 or 106 has been issued. When there is no stop command, the process proceeds to step S4.

In step S9, when the operation of the remote control devices 104 and 106 in step S7 has passed for a predetermined period of time, or when the power supply stop command has been transmitted by the input of the operation switch 240 in step S8, the control device 100
Stores the setting data and control data transferred from the remote control devices 104 and 106 in the RAM 114 or the EEPROM 11
8 is stored. Then, the power supply to the remote control devices 104 and 106 is stopped, and the voltage V
_{Apply L} and transition to the standby state.

In the flowchart of FIG. 5, the control device 1 is controlled when the driving power of the remote control devices 104 and 106 is restored.
Although the setting data etc. are transferred from 00, EEPRO
M208 stores the setting data and the like, and after the memory check, reads the setting data and the like from the EEPROM 118,
The operation of the remote control devices 104 and 106 may start to return.

As a result of such power supply control, conventionally,
While power consumption is caused by power supply of about 5 V, power saving power supply of 0.4 V or less is realized at the time of power supply standby by operation of the depolarizing circuit 226 and the small current generating circuit 236 configured by the diode bridge. , Power consumption can be reduced to a negligible level,
The return operation from the remote control devices 104 and 106 can be realized by the flow of the small current, and a highly convenient hot water supply system capable of power saving and automatic return can be realized.

In the embodiment, the remote controller of the hot water supply / reheating system has been described as an example. However, the present invention can be applied to various devices using a remote controller that supplies power through a communication cable.

Further, in the embodiment, the case where the backflow prevention circuit 142 is constituted by the diodes 301 and 318 has been described.
It may be constituted by a circuit using active elements such as transistors.

[0046]

As described above, according to the present invention,
When power is supplied to the remote controller using a microcomputer, such as a water heater, through the communication cable from the controller, the power consumption of the remote controller can be reduced, and the necessary power supply can be restored arbitrarily. Power consumption can be reduced without any loss.

[Brief description of the drawings]

FIG. 1 shows a hot water supply system according to an embodiment of the present invention.
It is a figure which shows the whole structure of a reheating apparatus.

FIG. 2 is a block diagram illustrating an embodiment of a control device.

FIG. 3 is a block diagram showing an embodiment of the remote control device.

FIG. 4 is a circuit diagram showing an embodiment of a control device and a remote control device.

FIG. 5 is a flowchart showing the operation of the hot water supply system.

[Explanation of symbols]

 2 Hot water supply / reheating unit (water heater) 100 Control device (control means) 102 Communication cable 104, 106 Remote control device 134 Switch circuit (power supply switching means) 140 Voltage detection circuit (voltage detection means) 146 Positive side cable 148 Negative side cable 242 Return switch (input means)

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission Date] October 16, 2000 (2000.10.
16)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

Claims (6)

[Claims] 1. A hot water supply system comprising a control device on the side of a water heater and a remote control device, wherein power is supplied to the remote control device from the control device via a communication cable. Power supply switching means for switching between standby power supply such as low-voltage power supply, input means for inputting a command for switching between normal power supply and standby power supply to the remote control device side; and A hot water supply system, comprising: a control unit that controls the power supply to the remote control device to switch between the normal power supply and the standby power supply. 2. The remote control device according to claim 1, further comprising: a switch as the input unit, and a voltage detecting unit for detecting a voltage change caused by an operation of the switch during the standby power supply. The hot water supply system according to claim 1, wherein the power supply is switched to the hot water supply system. 3. The hot water supply system according to claim 1, wherein, when shifting to the standby power supply, the control information stored in the storage unit of the remote control device is transferred to the storage unit of the control device immediately before the standby power supply. . 4. The hot water supply system according to claim 1, wherein, when shifting to the normal power supply, control information stored in the control device is transferred to storage means in the remote control device. 5. The hot water supply system according to claim 1, wherein when a predetermined time elapses after starting the normal power supply, the power supply to the remote controller is switched to the standby power supply. 6. The hot water supply system according to claim 1, wherein the power supply to the remote control device is switched based on running water detection in a heat exchanger of the water heater.