JPH10306944A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater for quickly supplying hot water at the time of starting supply of hot water of an instantaneous water heater. SOLUTION: This water heater comprises a gas burner 36 for heating a heat exchanger 10 connected with a feed water tube 11 and a hot water supply tube 12, a hot water temperature detector 15, an air detector 18, and a water amount detector 13 for detecting flow of water. When the flow of the water is detected by the detector 13, normal water heater is controlled according to a hot water temperature setter 34. When the flow of the water is not detected by the detector 13, after temperature detected by the detector 15 becomes a predetermined temperature or lower, a master solenoid valve 38 is opened, it is heated by the burner 36, and when it is heated for a predetermined time set by a timer 32, combustion is stopped, and this operation is repeated, temperature of the exchanger 10 is always held high to quickly supply hot water at the time of starting a supply of the hot water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instant hot water supply apparatus capable of supplying hot water quickly at the start of hot water supply.

[0002]

2. Description of the Related Art Conventionally, there is a hot water supply apparatus of this type as shown in FIG. 6 (for example, Japanese Patent Publication No. 4-9972).

[0003] In the figure, reference numeral 1 denotes an instantaneous water heater, and the instantaneous water heater 1 and a hot water supply port 2 are connected by a hot water supply pipe 3.
A hot water supply valve 4 is provided in front of the hot water supply port 2, and a drain pipe 5 branches off from an upstream side of the hot water supply valve 4 of the hot water supply pipe 3. The drain pipe 5 is provided with a drain valve 6. . Further, a temperature detecting section 7 is provided at a branch portion of the drain pipe 5 from the hot water supply pipe 3, and a set temperature of the temperature setting device 8 and the temperature detecting section 7 are set.
The hot water supply control section 9 controls the hot water supply valve 4 and the drainage valve 6 by comparing the temperatures.

When the temperature of the hot water detected by the temperature detector 7 at the time of the hot water supply request is within the allowable range of the set temperature of the temperature setting device 8, the hot water supply valve 4 is opened and the hot water in the hot water supply pipe 3 is supplied to the hot water supply port 2. In addition to the supply, when the temperature is outside the allowable range, the drain valve 6 is opened, the hot water in the hot water supply pipe 3 is discarded from the drain through the drain pipe 5, and hot water having a temperature within the allowable range is always supplied from the hot water supply port 2. is there.

[0005]

However, in the conventional hot water supply apparatus described above, it is necessary to install the hot water supply valve 4, the drain pipe 5, the drain valve 6, the temperature detecting section 7 and the like by performing piping work and wiring work on site. There is a hot water supply valve 4, drain pipe 5,
There is a problem that members such as the drain valve 6 and the temperature detection unit 7 are required.

If the temperature of the hot water is out of the allowable range at the time of the hot water supply request, the drain valve 6 is opened and the hot water in the hot water supply pipe 3 is discarded from the drain. The problem was that time could not be significantly improved.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a hot water supply apparatus capable of supplying hot water quickly at the start of hot water supply by improving the hot water supply apparatus itself.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and comprises a heat exchanger having a water supply pipe and a hot water supply pipe connected thereto, a heating means for heating the heat exchanger, and a heat exchanger. Temperature detection means for detecting the temperature in the vicinity of the outlet of the water, flow detection means for detecting the flow of water, and heating of the heat exchanger is started when the temperature detected by the temperature detection means when the flow is stopped falls below a predetermined temperature. When a predetermined time or temperature is reached, heating is stopped, and a controller that controls hot water supply temperature based on a signal from the temperature detecting means when the flow detecting means detects the flow of water is provided. During the time, when the temperature detected by the temperature detecting means falls below the predetermined temperature, the heating control means is controlled to start heating the heat exchanger by the heating means, and when the temperature reaches a preset time or temperature, the heating is stopped. , This prevents the heat exchanger from being cooled when the hot water is stopped, and allows the hot water to be quickly supplied to the terminal when the hot water is resupplied. The hot water supply temperature control is performed based on a signal, and the flow stop control and the flow control are performed based on a signal of one temperature detecting means.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A hot water supply apparatus according to a first aspect of the present invention includes a heat exchanger connected to a water supply pipe and a hot water supply pipe, heating means for heating the heat exchanger, and an outlet of the heat exchanger. A temperature detecting means for detecting a temperature in the vicinity, a flow detecting means for detecting a flow of water, and a temperature detected by the temperature detecting means when the stop of the flow of water is detected by the flow detecting means. When the heating means starts heating the heat exchanger by the heating means and stops heating when a preset time or temperature is reached, and when the flow detecting means detects the flow of water by the flow detecting means, The apparatus is provided with a controller for controlling the heating means based on a signal from the temperature detection means and performing control during flow. Then, when the hot water supply is stopped, the flow stoppage of the water is detected by the flow detection unit, and when the temperature detected by the temperature detection unit becomes equal to or lower than the predetermined temperature, heating of the heat exchanger by the heating unit is started for a predetermined time. Alternatively, by stopping the heating when the temperature is reached, the heat exchanger is prevented from being cooled when the hot water supply is stopped, so that the hot water can be quickly supplied to the terminal at the time of hot water supply when the hot water is supplied again. Based on the signal of the temperature detecting means, the control of the flow stop when the flow of the water is stopped and the control of the flow during the flow of the water are performed.

[0010] In addition, the hot water supply apparatus according to a second aspect of the present invention is configured such that, in addition to the configuration of the first aspect, a temperature detecting means is provided upstream of a descending portion of a hot water supply pipe connected to a heat exchanger outlet. Things. Then, in the flow stop control, the temperature state in the heat exchanger can be accurately estimated, and accurate control is realized.

A hot water supply apparatus according to a third aspect of the present invention, in addition to the configuration of the first aspect, further comprises an air detecting means for detecting an air bite in a heat exchanger or a piping system connected to an outlet of the heat exchanger. The controller is provided on the downstream side of the descending portion of the pipe, and the controller does not heat the heat exchanger by the heating means when the air detector detects the air bite. Then, when air is interposed in the heat exchanger due to water cutoff or drainage of the hot water supply device, heating of the heat exchanger is stopped to ensure safety.

Further, a hot water supply apparatus according to a fourth aspect of the present invention is configured such that, in addition to the configuration of the first aspect, the controller stops the flow stop control when a predetermined time is exceeded. In addition, the flow stop control is not performed indefinitely, and wasteful energy consumption when the user is absent for a long time is prevented.

In the hot water supply apparatus according to a fifth aspect of the present invention, the controller is configured to start the flow stop control at a predetermined time. Then, when the user is unable to instruct driving, such as in the morning, heating is started when the time is reached, thereby further increasing convenience.

A hot water supply apparatus according to a sixth aspect of the present invention includes a hot water supply temperature setting device, and the controller changes a predetermined temperature at which heating is started based on the set temperature of the hot water supply temperature setting device. is there. Then, a temperature close to the hot water supply temperature setting can be quickly supplied, and the set temperature at the time of use can be obtained quickly, thereby further improving usability.

A water heater according to a seventh aspect of the present invention is a heat exchanger in which a water supply pipe and a water supply pipe are connected, a heating means for heating the heat exchanger, and a temperature in the vicinity of the heat exchanger outlet. Temperature detection means for detecting the flow of water, the flow detection means for detecting the flow of water, and when the temperature detected by the temperature detection means when the flow detection means detects the stop of the flow of water is below a predetermined temperature Starting the heating of the heat exchanger by the heating means and performing a flow stop time control to stop the heating when a predetermined time or temperature is reached, and detecting the temperature despite the flow stop time control being performed. When the temperature detected by the means is equal to or lower than a predetermined temperature, the controller is provided with a controller for performing control at the time of the next stop of the flow at intervals in time. Then, heating is not continuously performed at the time of a cold start in which the temperature of the heat exchanger is low, thereby preventing local boiling and preventing an abnormal increase in pressure in the water heater.

Further, in the hot water supply apparatus according to an eighth aspect of the present invention, in addition to the configuration of the seventh aspect, after the control at the time of the stop of the flow, the controller detects that the temperature detected by the temperature detecting means exceeds a predetermined temperature. The control at the time of the flow stop is performed without performing the control at intervals in time. By eliminating the control with a time interval, unnecessary heating is prevented, and abnormal temperature rise and abnormal pressure rise inside the heat exchanger are prevented.

A hot water supply apparatus according to a ninth aspect of the present invention, in addition to the configuration of the first or seventh aspect, further comprises a bypass pipe for bypassing the heat exchanger and a bypass flow rate control for adjusting the bypass flow rate to the bypass pipe. Means for closing the bypass flow rate control means when the flow is stopped. When the flow stops, the hot water in the heat exchanger naturally circulates through the bypass path, thereby preventing heat radiation from being promoted.

The air detecting means according to a tenth aspect of the present invention, in addition to the structure of the first or seventh aspect, further comprises a bypass pipe for bypassing the heat exchanger, and a bypass flow rate for adjusting the bypass flow rate to the bypass pipe. When the temperature detected by the temperature detecting means exceeds the upper limit temperature, the bypass flow rate controlling means is opened. If the temperature of the hot water in the heat exchanger is too high, water is mixed from the bypass pipe at the time of hot water supply to lower the hot water supply temperature, thereby preventing the danger of supplying hot water.

Further, in the eleventh aspect of the present invention, the air detecting means is the same as the first or seventh aspect, and the controller comprises:
When the flow detecting means detects the flow of the water even during the flow stop control, the flow stop control is stopped. Then, when the flow of water is detected, it is determined that hot water supply has been started, and by immediately switching to normal hot water supply, a quick rise in temperature during use is realized.

In the twelfth aspect of the present invention, in addition to the first or seventh aspect, when the temperature detected by the temperature detecting means during the flow stop control exceeds the upper limit temperature, It is configured such that heating of the heat exchanger by the heating means is stopped. When the temperature inside the heat exchanger rises further due to the failure of the heating control or the empty heating, heating is stopped to ensure safety.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment) FIG. 1 is a system diagram of a hot water supply apparatus according to an embodiment of the present invention. In FIG. 1, a water supply pipe 11 and a hot water supply pipe 12 are connected to a heat exchanger 10. In the water supply pipe 11,
A water amount detector 13 as flow detection means for detecting inflow of water into the heat exchanger 10 and a water temperature detector 14 for detecting water temperature are provided. In the hot water supply pipe 12 at the outlet of the heat exchanger 10,
Hot water temperature detector 1 using a thermistor as temperature detecting means
5 are provided. In addition, a bypass pipe 16 is provided to bypass the heat exchanger 10 and connect the water supply pipe 11 and the hot water supply pipe 12, and the bypass pipe 16 is configured to mix water from the bypass pipe 16 with hot water from the heat exchanger 10. A water proportional valve 17 is provided as bypass flow rate control means for adjusting the ratio. The water proportional valve 17 has a valve which is balanced with the water pressure by adjusting the current to the solenoid.
The normal open type which is fully opened by stopping the electric current is used to adjust the opening degree of the water and the amount of water passing therethrough. An air detector 18 is provided in the hot water supply pipe 12, and a water amount control valve 19 and a mixed water temperature detector 20 are provided after the junction of the bypass pipe 16.

The hot water supply pipe 12 is further connected to a hot water supply pipe 22 outside the hot water supply apparatus main body 21, and a hot and cold water mixing tap 23 provided at a terminal is provided.
24. On the terminal side, a remote controller 25 of the water heater main body 21 is provided. The remote controller 25 is of a wireless type, and includes a power switch 26, a hot water supply up switch 27, a down switch 28, a display unit 29,
A preheating switch 30 is provided for selecting control to preheat the heat exchanger 10 when hot water is not used. The main body controller 31 has a timer 32 for setting the operation start time of the hot water supply device. The power from the commercial power supply is supplied, and the signal of the remote controller 25 and the signals of various sensors received by the receiver 33 are taken in. Also, signals and operation outputs to various actuators are output.

The controller 31 of the water heater main body 21 is provided with a flow control unit 34 and a flow stop control unit 35. The heat exchanger 10 includes a gas burner 3 serving as a heating unit.
6, a gas proportional valve 37 is provided as a part of a heating adjusting means for adjusting the amount of gas to the gas burner 36. The gas is turned on and off by a main solenoid valve 38 which forms another part of the heating control means, and air is blown from a blower fan 39 before, after, and during combustion.

The hot water temperature detector 15 attached to the hot water supply pipe 12 and the air detector 18 are mounted in a positional relationship as shown in FIG. The hot water temperature detector 15 is connected to the lower part 40 of the hot water supply pipe 12 connected to the outlet of the heat exchanger 10.
Is provided on the upstream side.

This is because if provided downstream of the descending portion 40, the hot water in the heat exchanger 10 does not naturally convect to the hot water temperature detector when the flow stops, so that the temperature state in the heat exchanger 10 can be accurately determined. This is to prevent the estimation from becoming impossible. The air detector 18 is provided near the downstream side of the descending portion 40 of the hot water supply pipe 12. This is a drain valve 4 to prevent freezing
At the time when water is drained by opening 1, 42, even if a small amount of water is drained, it is surely replaced with air, and it is close to the heat exchanger 12 and has an effect on the temperature rise of the heat exchanger 12 when air is caught. It has been selected as a place where it can detect the influence of air. Although a method of providing the water supply pipe 11 corresponding to the drain valve 42 is also conceivable, it is more reliable to provide it on the upper side of the heat exchanger 10.

The air detector 18 is configured as shown in FIG. The air detector 15 is configured such that a thermistor 44 protected by a protective tube 43 is filled with a filler 45 and a lead wire 46 is exposed to the outside. It is attached to. Then, the thermistor 44 is temporarily heated by applying a high voltage different from that at the time of temperature detection, and after the temperature is stabilized, the resistance of the thermistor 42 is measured. Or judge. In addition, this air detector measures the resistance value before heating with applied voltage, determines the ambient temperature, and performs temperature compensation to accurately determine whether it is water or air. ing.

Next, the operation of this embodiment will be described. The operation is shown in the flowchart of FIG.

When the power switch 26 of the remote controller 25 is simply turned on and the timer 32 reaches a set time and is turned on (S1), the water amount control valve 19 is fully opened (S1).
2) The water proportional valve 17 is kept fully open (S3), the original solenoid valve 38 and other components are controlled to stop combustion (S4), and the blower fan 39 is also stopped (S5). In this state, the hot / water mixer tap 23 or 24 is opened and the water amount detector 13
When the amount of water detected at step S1 exceeds the ignition flow rate (S6), the heating mode for normal hot water supply is entered. Then, in order to supply hot water of the set temperature by operating the up switch 27 and the down switch 28 of the remote controller 25, the mixed water temperature detected by the mixed water temperature detector 20 by the flowing time control unit 34 is compared with the set temperature. Is done. Further, the tapping temperature detected by the tapping temperature detector 15 and the tapping temperature set by the flow control unit 34 are compared, and the water temperature of the water temperature detector 14 and the value of the water amount detector 13 are taken in. The water proportional valve 17 and the water amount control valve 19 are adjusted, and hot water at a desired temperature is supplied from the hot water supply pipe 22.

When the flow rate of the water detected by the water amount detector 13 is equal to or less than the ignition flow rate, or when the hot water supply is stopped,
When the preheating switch 30 is turned on, a heating mode for the heat exchanger 10 at the time of stopping hot water supply is enabled (S7). Then, first, the heating start temperature is determined (S8). This determination is made based on the set temperature set by the remote controller 25. For example, when the set temperature is 40 ° C., the heating start temperature is 50 ° C., when the set temperature is 35 ° C., it is 47 ° C.,
In the case of 45 ° C., the temperature is determined based on a table stored in advance corresponding to the set temperature, such as 53 ° C.

Then, the temperature of the hot water temperature detector 15 is detected. If this temperature is lower than the heating start temperature (S10),
It is confirmed that a predetermined time (70 seconds) has passed since the previous heating of the air detector 18 (S11). Subsequently, it is confirmed by the air detector 18 that water is filled in the heat exchanger 10 (S12). The detection operation of the air detector 18 is as shown in FIG. First, the ambient temperature is measured by the thermistor 42 of the air detector 18. Then, the circuit voltage is raised from the normal level, energization is performed for 3 seconds, for example, and the thermistor 42 performs self-heating. One second after the power is turned off, the resistance of the thermistor 42 is measured, and the state of the temperature change is checked to determine whether the surroundings are air or water. Then, the water proportional valve 17 is opened (S13), the blower fan 39 is rotated, the original solenoid valve 38 is opened, and the burner 36 is started (S14). Then, for example, after igniting and burning for 1 second,
The gas proportional valve 37 is used to reduce the combustion amount to the minimum, and burn for another 6 seconds. If the temperature detected by the hot water temperature detector 15 rises abnormally (65 ° C. or more) during the heating of the heat exchanger 10, the air bite into the heat exchanger 10 when the air detector 18 fails,
Alternatively, it is determined that the combustion is abnormal due to the failure of the heating control system, and the operation for stopping the heating is started (S15). If the temperature rises abnormally, the water proportional valve 17 is opened so that the water in the bypass pipe 16 can always be mixed and supplied even if the hot / water mixer tap 23 or 24 is opened under such circumstances. In addition, care is taken not to supply hot water to the terminal. When it is determined that 9 seconds have elapsed including the exhaust operation before and after the combustion of the blower fan 39 (S16), the combustion operation is stopped (S17). With the stop of the combustion, the water proportional valve 17 is closed (S18), and the natural circulation of the hot water of the heat exchanger 10 through the bypass pipe 16 prevents the heat radiation from being promoted. If there is no time interval (5 minutes) from the heating operation at the time of the previous flow stop, the next combustion operation does not occur (S19). At the time of a cold start in which the operation is started from a state where the heat exchanger 10 is cold,
The temperature does not rise sufficiently in one combustion operation, but if it is heated continuously, the temperature distribution in the heat exchanger 10 becomes uneven, and the internal pressure tends to rise abnormally. Control. In addition, in the operation at the time of the stoppage of the flow, the user can alleviate the uncomfortable feeling that the operation is performed when not in use.

The heating operation when the flow is stopped is performed for a predetermined time (1 hour)
If the number exceeds the threshold, the operation is stopped (S20). By this operation, the flow stop control is not performed indefinitely, preventing energy from being wasted when the user is absent for a long time, and preventing suspicion of others when absent. Is what it is.

The above is an operation in a state where the timer 32 is on. However, if the predetermined time has not been reached, the above operation is not performed. By attaching the timer 32, when the user is sleeping and cannot directly instruct driving, such as at the beginning of the morning, heating is started when it is on time, further increasing the convenience at the start of use, and It can be operated only during the time when hot water is used, and both energy saving and convenience can be achieved.

The controller uses the flow detector 13 to determine the predetermined flow rate (2.
When the flow of water of 8 l / min or more is detected, the process immediately shifts to interrupt control and shifts to a normal hot water supply mode. This operation is not represented in FIG.

With the above operation, assuming a general household water heater, the conventional water heater has a pipe length of 5 mm.
about 15m after twisting the terminal faucet
What normally takes about two seconds to supply hot water can be reduced to about five seconds.

In the conventional hot water supply apparatus, it takes about 10 seconds for the hot water supply apparatus itself to rise due to the amount of water retained, and about 5 seconds to push out the amount of water retained in the piping. Since the time can be shortened, only the time required for pushing out the staying water in the pipe is required.

In this embodiment, as an example of the heating means, heating by the gas burner 36 is used, but a petroleum burner or means for electrically heating may be used.

The temperature detector 15 is used as a temperature detector.
However, various methods such as a thermistor and a resistor may be used as a sensor instead of a type that can be exposed in the hot water supply pipe 12 and a type attached to a surface.

Further, the flow detecting means has been described by taking the water amount detector 13 as an example. However, the flow detecting means is indirectly linked with the operation switch for starting and stopping the hot water supply, or the direct and indirect ones are combined. Or other formats.

Also, an electric method using a thermistor as the air detecting means is taken as an example. A water level detecting method using an electrode, a method having a mechanical float, and detecting the composition of air (for example, nitrogen) are used. Various methods can be considered, such as an optical method using a difference in refractive index between water and air.

The water proportional valve 1 is used as bypass control means.
7 was taken as an example, a method of combining a plurality of solenoid valves,
Various methods such as a method using a motor valve are conceivable.

[0041]

As described above, according to the hot water supply apparatus of the present invention, the following effects can be obtained.

(1) It is detected by the flow detecting means that the flow of water to the heat exchanger has stopped when the hot water supply is stopped, and when the temperature detected by the temperature detecting means falls below a predetermined temperature, the heating means By starting the heating of the heat exchanger by heating and stopping the heating when the temperature reaches a predetermined time or temperature, the heat exchanger is prevented from being cooled when the hot water supply is stopped, and to the terminal at the time of hot water supply when re-hot water is supplied Hot water can be supplied quickly, and control of flow stop when water flow stops and flow control of normal hot water supply when water flows can be performed based on a signal from one temperature detecting means.

(2) Since the temperature detecting means is provided on the upstream side of the descending portion of the hot water supply pipe connected to the heat exchanger outlet, the heat exchanger is controlled by natural convection to the temperature detecting means in the flow stop control. Since the hot water in the inside circulates, the temperature state in the heat exchanger can be accurately estimated by the temperature detecting means, and accurate control can be realized.

(3) The air detecting means is provided downstream of the descending portion of the hot water supply pipe connected to the outlet of the heat exchanger, and when the air detector detects the air bite, the heating means heats the heat exchanger. The heating of the heat exchanger can be stopped at the beginning of installation, when the water is cut off, and when air is interposed in the heat exchanger due to drainage to prevent freezing, Performance can be improved.

(4) Since the controller stops the flow stop control when the flow stop time exceeds a predetermined time, the flow stop control can be performed indefinitely, and when the user is absent for a long time or not used for a long time. Sometimes, energy can be prevented from being wasted.

(5) In order to start the flow stop control at a predetermined time, heating is started when the user is unable to instruct the operation, such as the first time in the morning, and when the time is on time,
The heating control of the flow stop control can be performed only in the time period when the frequency of use is high, and the convenience can be further increased.

(6) A hot water temperature setting device is provided, and the controller changes the predetermined temperature for starting heating based on the set temperature of the hot water temperature setting device, so that a temperature close to the hot water temperature setting can be quickly supplied. At the start of hot water supply, hot water of the set temperature is quickly obtained, and further improvement in usability can be achieved.

(7) Heating is not continuously performed at the time of cold start when the temperature of the heat exchanger is low, thereby preventing local boiling and preventing an abnormal increase in pressure in the water heater.

(8) By closing the bypass passage, natural circulation of the hot water in the heat exchanger when the hot water supply is stopped can be prevented, and the heat retaining effect after the heat exchanger is heated when the flow is stopped can be enhanced.

(9) Since the bypass flow rate control means is closed when the flow stops, it is possible to prevent the hot water in the heat exchanger from circulating naturally through the bypass path and promoting heat radiation, and to prevent the ignition frequency and energy The consumption can be reduced.

(10) The bypass pipe is provided with a bypass flow rate control means for adjusting the bypass flow rate, and when the temperature detected by the temperature detection means exceeds the upper limit temperature, the bypass flow rate control means is opened to provide heat exchange. If the temperature of the hot water in the vessel is too high, water can be mixed from the bypass pipe at the time of hot water supply to lower the hot water supply temperature, thereby preventing hot water from being supplied.

(11) If the flow detecting means detects the flow of water even during the heating control at the time of the flow stop, the heating control at the time of the flow stop is stopped, and it is determined that the hot water supply has been started, and the water supply is immediately started. By switching to normal hot water supply, a quick rise in temperature can be realized when using normal hot water supply.

(12) When the temperature detected by the temperature detecting means exceeds the upper limit temperature during the heating control at the time when the flow stops, the heating of the heat exchanger by the heating means is stopped to prevent a malfunction in the heating control or an empty state. Abnormal heat exchanger temperature due to boil can be prevented, and combustion can be stopped to ensure safety.

[Brief description of the drawings]

FIG. 1 is a system diagram of a hot water supply apparatus according to a first embodiment of the present invention.

FIG. 2 is a peripheral configuration diagram of a heat exchanger used in the water heater.

FIG. 3 is a cutaway sectional view of a main part of the air detector used in the water heater.

FIG. 4 is a flowchart of an operation of a main part of the water heater.

FIG. 5 is an explanatory diagram of the operation of the air detector used in the hot water supply device.

FIG. 6 is a system diagram of a conventional hot water supply apparatus.

[Explanation of symbols]

 Reference Signs List 10 heat exchanger 11 water supply pipe 12 hot water supply pipe 13 water quantity detector (flow detection means) 15 hot water temperature detector (temperature detection means) 16 bypass pipe 17 water proportional valve (bypass flow rate control means) 18 air detector (air detection means) ) 27 Up switch (hot water temperature setting device) 28 Down switch (hot water temperature setting device) 31 Controller 36 Gas burner (heating means)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kiyotaka Miyazaki 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 72) Inventor Masahiko Yamamoto 1006 Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd.

Claims (12)

[Claims] 1. A heat exchanger to which a water supply pipe and a hot water supply pipe are connected,
Heating means for heating the heat exchanger, temperature detecting means for detecting the temperature near the outlet of the heat exchanger, flow detecting means for detecting the flow of water, and stopping the flow of water with the flow detecting means. When detecting, when the temperature detected by the temperature detecting means falls below a predetermined temperature, heating of the heat exchanger by the heating means is started, and when the temperature reaches a preset time or temperature, the heating is stopped. A hot water supply apparatus comprising: a controller that controls the heating unit based on a signal from the temperature detection unit and controls the flow when the flow is detected by the control and the flow detection unit. 2. The hot water supply apparatus according to claim 1, wherein the temperature detecting means is provided upstream of a descending portion of the hot water supply pipe connected to the outlet of the heat exchanger. 3. An air detecting means for detecting air entrapment of a heat exchanger or a piping system is provided downstream of a descending portion of a hot water supply pipe connected to an outlet of the heat exchanger, and the controller detects the air entrapment by the air detector. The hot water supply apparatus according to claim 1, wherein heating of the heat exchanger by the heating means is not performed when the temperature is detected. 4. The hot water supply apparatus according to claim 1, wherein the controller stops the heating control at the time of stopping the flow when the flow exceeds a predetermined time. 5. The hot water supply apparatus according to claim 1, wherein the controller starts the heating control at the time when the flow stops at a predetermined time. 6. The hot water supply apparatus according to claim 1, further comprising a hot water temperature setting device, wherein the controller changes a predetermined temperature at which the heating is started based on the set temperature of the hot water temperature setting device. 7. A heat exchanger to which a water supply pipe and a hot water supply pipe are connected,
Heating means for heating the heat exchanger, temperature detecting means for detecting a temperature near the heat exchanger outlet, flow detecting means for detecting the flow of water, and detecting the stop of the flow of water with the flow detecting means. When the temperature detected by the temperature detecting means is equal to or lower than a predetermined temperature during the heating, the heating means starts heating the heat exchanger and stops the heating when a predetermined time or temperature is reached. And
If the temperature detected by the temperature detecting means is equal to or lower than a predetermined temperature in spite of performing the flow stop control, a hot water supply provided with a controller for performing the next flow stop control at a time interval. apparatus. 8. The controller according to claim 7, wherein, after the control at the time of the stoppage of the flow, if the temperature detected by the temperature detecting means exceeds a predetermined temperature, the control at the time of the stoppage of the flow thereafter does not perform the control with a time interval. The hot water supply device as described. 9. A bypass pipe for bypassing a heat exchanger and a bypass flow rate control means for adjusting a bypass flow rate in the bypass pipe, wherein the bypass flow rate control means is closed when the flow is stopped. 7. The hot water supply device according to 7. 10. A bypass pipe for bypassing a heat exchanger,
8. The bypass flow control device according to claim 1, wherein said bypass pipe is provided with bypass flow control means for adjusting a bypass flow rate, and said bypass flow control means is opened when a temperature detected by said temperature detection means exceeds an upper limit temperature. Water heater. 11. The hot water supply apparatus according to claim 1, wherein the controller stops the flow stop control when the flow detecting means detects the flow of the water even during the flow stop control. . 12. The hot water supply according to claim 1, wherein when the temperature detected by the temperature detection means exceeds the upper limit temperature during the flow stop control, heating of the heat exchanger by the heating means is stopped. apparatus.