JP2017083085A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater capable of having more opportunities for fault detection on a hot water supply temperature sensor and a water supply temperature sensor.SOLUTION: A water heating inhibition part 22 inhibits a hot water supply operation when water heating inhibition conditions where hot water supplied from a hot water supply path 2 reaches an abnormal temperature are met. When a water supply flow rate sensor 42 detects a flow rate equal to or higher than a working flow rate while the water heating inhibition part 22 inhibits the hot water supply operation, a fault notification part 23 integrates a detected flow rate of the water supply flow rate sensor 42, determines whether a first temperature difference as a temperature difference between a detected temperature Tout of the hot water temperature sensor 45 and a detected temperature Tin of the water supply temperature sensor 43 is equal to or larger than a first determination value when the integrated value reaches a predetermined value or higher, and performs first fault notification for giving notice of a fault of the hot water temperature sensor 45 or water supply temperature sensor 43 when the first temperature difference is equal to or larger than the first determination value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hot water supply device having a failure detection function of a temperature sensor.

  Conventionally, a hot water supply apparatus having a function of detecting a failure of a temperature sensor such as a hot water supply temperature sensor has been proposed (see, for example, Patent Documents 1 and 2).

  In the hot water supply apparatus described in Patent Document 1, a predetermined time (assuming a time during which the temperature of water in the water flow path of the hot water supply apparatus is equalized by natural cooling is uniformed from the time when the hot water supply is stopped and the burner is extinguished. When the difference between the detected temperatures is equal to or higher than a predetermined level after comparing the detected temperature of the hot water temperature sensor with the detected temperature of the hot water temperature sensor, one of the temperature sensors has failed. Judge.

  In the hot water supply apparatus described in Patent Literature 2, when the hot water supply operation is stopped (the burner is extinguished) and water is passed through the hot water supply passage, the detected temperature of the hot water temperature sensor and the detected temperature of the hot water temperature sensor If the detected temperature of the hot water temperature sensor is lower than the detected temperature of the hot water temperature sensor, it is determined that the hot water temperature sensor has deteriorated.

JP-A-8-327146 Japanese Patent Laid-Open No. 5-106836

  In the hot water supply apparatus described in Patent Document 1, the set predetermined time may be longer depending on the length of the water passage, the amount of retained water, the amount of retained heat, and the like. In this case, there is an inconvenience that hot water supply is resumed before a predetermined time elapses after the hot water supply is stopped, and a failure detection process for the hot water supply temperature sensor and the water supply temperature sensor is not performed.

  Moreover, in the hot water supply apparatus described in Patent Document 2, water is passed from the water supply pipe to the hot water discharge pipe in a state where the hot water supply operation is stopped when the water is added to the bathtub or by the user. Only when the operation is turned off. For this reason, there is a disadvantage that the user does not add water and the failure detection process of the hot water temperature sensor and the water temperature sensor is not performed when the hot water supply device is used with the operation always on.

  As described above, in the hot water supply apparatus described in Patent Documents 1 and 2, the hot water temperature sensor and the condition for executing the failure detection of the water temperature sensor depend on the usage state of the hot water supply apparatus by the user. Therefore, the state where failure detection is not performed continues depending on use conditions, and there is a possibility that discovery of failure of the hot water supply temperature sensor and the supply water temperature sensor may be delayed.

  This invention is made | formed in view of this background, and it aims at providing the hot water supply apparatus which can perform the failure detection process of a hot water supply temperature sensor and a water supply temperature sensor irrespective of the use condition of a hot water supply apparatus. .

The hot water supply apparatus of the present invention is
A water heating unit that is provided in the middle of the hot water supply path and heats the water flowing through the hot water supply path;
A water supply temperature sensor for detecting the temperature of water in the hot water supply channel upstream of the water heating unit;
A hot water supply temperature sensor for detecting the temperature of hot water in the hot water supply path downstream of the water heating unit;
A water supply flow rate sensor for detecting a flow rate of water flowing through the hot water supply path;
When a flow rate equal to or higher than a predetermined operating flow rate is detected by the water supply flow rate sensor, a hot water supply operation is performed to adjust the heating power of the water heating unit so that the detected temperature of the hot water temperature sensor becomes a target hot water supply temperature. A hot water supply control unit,
A water heating prohibition unit that prohibits heating of water flowing through the hot water supply path by the water heating unit when a water heating prohibition condition is established in which the temperature of hot water supplied from the hot water supply path becomes abnormal;
In a state where heating of the water flowing through the hot water supply passage by the water heating portion is prohibited by the water heating prohibition portion, water supply to the hot water supply passage is detected by the water supply flow rate sensor, and by water supply to the hot water supply passage, Detection of the hot water temperature sensor when the temperature of the water in the hot water supply passage between the location of the hot water temperature sensor and the location of the hot water temperature sensor is assumed to be uniform. It is determined whether or not a first temperature difference that is a temperature difference between the temperature and a temperature detected by the feed water temperature sensor is equal to or greater than a first determination value, and the first temperature difference is equal to or greater than the first determination value And a failure notification unit for performing a first failure notification for notifying a failure of the hot water supply temperature sensor or the water supply temperature sensor.

  According to the present invention, the failure notification unit is configured such that the water heating prohibition condition is satisfied, and the water supply flow rate sensor supplies water to the hot water supply channel in a state where heating of the water flowing through the hot water supply channel is prohibited. It is assumed that the temperature of the water in the hot water supply path between the location where the hot water supply temperature sensor is provided and the location where the hot water supply temperature sensor is provided has become uniform due to the detected water supply to the hot water supply route. The first temperature difference, which is the temperature difference between the temperature detected by the hot water temperature sensor and the temperature detected by the water temperature sensor, is determined to be greater than or equal to the first determination value.

  Here, in the situation where the temperature of the water in the hot water supply path between the location where the hot water temperature sensor is disposed and the location where the hot water temperature sensor is disposed is assumed to be uniform, the detected temperature of the hot water temperature sensor and the water temperature sensor When the first temperature difference that is the difference from the detected temperature is equal to or greater than the first determination value, it can be determined that at least one of the hot water supply temperature sensor and the water supply temperature sensor has failed. Therefore, in this case, the failure notification unit performs a first failure notification for notifying the failure of the hot water supply temperature sensor or the water supply temperature sensor.

  Thus, when heating of the water flowing through the hot water supply path by the water heating unit is prohibited due to establishment of the water heating prohibition condition, a hot water supply device by the user is detected by detecting a failure of the hot water supply temperature sensor or the water supply temperature sensor. Whether or not there is a failure in the hot water supply temperature sensor and the water supply temperature sensor can be determined without depending on the usage status of the hot water supply. Therefore, it is possible to increase the reliability of the hot water supply apparatus by reducing the possibility that the hot water temperature sensor or the state in which the hot water temperature sensor has failed is left unattended.

A bypass passage that bypasses the water heating section and communicates the upstream side and the downstream side of the water heating section of the hot water supply path;
A bypass ratio change valve that is driven by a stepping motor and changes a bypass ratio that is a ratio of a flow rate of water flowing through the bypass path to a flow rate of water flowing through the water heating unit;
A water heating part hot water temperature sensor for detecting the temperature of hot water supplied from the water heating part to the hot water supply path;
The hot water temperature sensor detects the temperature of the hot water in the hot water supply channel downstream of the hot water supply channel, rather than the downstream connection point with the bypass channel,
The hot water supply control unit adjusts the heating power of the water heating unit and the bypass ratio so that the detected temperature of the hot water supply temperature sensor becomes the target hot water supply temperature,
The water heating prohibition condition is that, during execution of the hot water supply operation, the detected temperature of the hot water supply temperature sensor is equal to or higher than a first determination temperature, or the detected temperature of the water heating unit hot water temperature sensor is equal to or higher than a second determination temperature. Is, and
When the first temperature difference is less than the first determination value when the failure notifying unit prohibits heating of the water flowing through the hot water supply path by the water heating unit by the water heating prohibiting unit, The prohibition of heating of the water flowing through the hot water supply path by the water heating unit is canceled.

  According to this configuration, when the stepping motor is out of step (state where the control position of the stepping motor deviates from the actual position) due to dust biting of the bypass ratio changing valve, the bypass ratio is controlled by the hot water supply control unit. There is a case where high temperature hot water is supplied from the water heating unit to the hot water supply path and the water heating prohibition condition is satisfied. Further, the water heating prohibition condition may be satisfied due to a failure of the hot water supply temperature sensor or the water supply temperature sensor.

  As described above, in this configuration, the factors that satisfy the water heating prohibition condition include step-out of the stepping motor and failure of the hot water supply temperature sensor or the water supply temperature sensor. Even when the water heating prohibition condition is satisfied by the stepping motor step-out, a failure determination of the hot water supply temperature sensor or the water supply temperature sensor is performed. A failure of the feed water temperature sensor can be detected and notified early.

In addition, a hot water filling passage that communicates a location downstream of the temperature detection location by the hot water temperature sensor of the hot water supply passage, and a bathtub,
A hot water temperature sensor for detecting the temperature of hot water in the hot water path,
When the hot water is being supplied from the hot water supply path to the bathtub through the hot water filling path, the failure notification unit is configured to detect a temperature difference between a detected temperature of the hot water temperature sensor and a detected temperature of the hot water temperature sensor. It is determined whether or not a certain second temperature difference is greater than or equal to a second determination value. When the second temperature difference is greater than or equal to the second determination value, a failure of the hot water supply temperature sensor or the hot water temperature sensor is detected. A second failure notification is made, and when the first temperature difference is greater than or equal to the first determination value in a state where the second failure notification has not been made before, a failure of the feed water temperature sensor is notified. The third failure notification is performed.

  According to this configuration, if the second failure notification has not been made before, there is a high possibility that the hot water temperature sensor has not failed. Therefore, in this state, when the first temperature difference (temperature difference between the detected temperature of the hot water supply temperature sensor and the detected temperature of the feed water temperature sensor) is equal to or higher than the first determination value, it is determined that the feed water temperature sensor has failed. can do. Therefore, by performing the third failure notification for notifying the failure of the feed water temperature sensor, it is possible to identify the cause of the failure and prompt the user to respond quickly.

The block diagram of a hot-water supply apparatus. The flowchart of a failure alerting | reporting process.

  An example of an embodiment of the present invention will be described with reference to FIGS. Referring to FIG. 1, a hot water supply apparatus 1 according to the present embodiment includes a hot water supply apparatus main body 1 and a remote controller 15 for remotely operating the hot water supply apparatus main body 1. The hot water supply device 1 has a hot water supply function of performing hot water supply operation to supply hot water from the hot water tap 6, and an automatic hot water filling function of performing hot water filling operation to fill a predetermined amount of hot water in the bathtub 5.

  The hot water supply apparatus 1 has a heat exchanger 30 provided in the middle of a hot water supply path 2 connected at one end to a water supply (not shown) and supplied with water from the water supply, a burner 31 for heating the heat exchanger 30, and a burner 31 A gas supply pipe 32 for supplying fuel gas, a gas main valve 35 for opening and closing the gas supply pipe 32, and a gas flow rate adjusting valve 34 for adjusting the supply flow rate of the fuel gas to the burner 31 by changing the opening of the gas supply pipe 32. Bypassing the heat exchanger 30 and connecting the upstream side and the downstream side of the heat exchanger 30 of the hot water supply path 2 on the downstream side of the downstream side connection point between the hot water supply path 2 and the bypass path 50 A hot water filling passage 7 branched from the hot water supply passage 2 and connected to the bathtub 5 and a controller 20 for controlling the overall operation of the hot water supply device 1 are provided. The heat exchanger 30, the burner 31, the gas supply path 32, the gas main valve 35, and the gas flow rate adjustment valve 34 constitute a water heating unit of the present invention.

  The controller 20 is connected to the remote controller 15 via the communication cable 16, and the user operates the remote controller 15 to target hot water supply temperature (temperature of hot water supplied from the hot water tap 6 by the hot water supply function), target hot water filling. A temperature (temperature of hot water supplied to the bathtub 5 by the automatic hot water filling function), a target hot water filling amount (amount of hot water supplied to the bathtub by the automatic hot water filling function), and the like can be set. Further, the user operates the remote controller 15 to change the hot water supply device 1 into an operating state (a state in which the hot water supply operation and the hot water filling operation are executed) and a standby state (a state in which the hot water supply operation and the hot water filling operation are not executed). Can be switched.

  The hot water supply path 2 includes a water temperature sensor 43 for detecting the temperature of water in the hot water supply path 2 upstream of the heat exchanger 30 (temperature of water supplied from the water supply to the hot water supply path 2, water supply temperature) Tin, hot water supply A water supply flow rate sensor 42 for detecting the flow rate of water flowing through the passage 2 (feed water flow rate), a flow rate adjusting valve 41 for adjusting the feed water flow rate, and the temperature of hot water supplied from the heat exchanger 30 to the hot water supply passage 2 (heat exchange hot water) (Temperature) Heat exchanging hot water temperature sensor 44 for detecting Thex (corresponding to the water heating portion hot water temperature sensor of the present invention), and a hot water supply path downstream of the downstream connection location of the hot water supply path 2 and the bypass path 50 A hot water temperature sensor 45 for detecting the temperature (hot water temperature) Tout of hot water in 2 is provided, and a hot water tap 6 is connected to the tip of the hot water supply path 2.

  The bypass path 50 is a bypass ratio change valve that adjusts the ratio (bypass ratio) of the flow rate of water flowing through the bypass path 50 to the flow rate of water flowing through the heat exchanger 30 by changing the opening of the bypass path 50. 51 is provided. The bypass ratio changing valve 51 is driven by a stepping motor 51a.

  The hot water filling path 7 includes a hot water filling valve 60 that opens and closes the hot water filling path 7, a hot water flow rate sensor 61 that detects the flow rate of hot water flowing through the hot water filling path 7, and the temperature of hot water in the hot water filling path 7 (hot water). A hot water temperature sensor 62 for detecting the tension temperature Tb is provided.

  In this embodiment, the thermistor is used as the feed water temperature sensor 43, the hot water temperature sensor 44, the hot water temperature sensor 45, and the hot water temperature sensor 62, but other types of temperature sensors may be used. .

  The controller 20 is an electronic circuit unit configured by a CPU, a memory, various interface circuits, and the like (not shown). By executing a control program for the hot water supply device 1 held in the memory by the CPU, the hot water supply control unit 21, It functions as the water heating prohibition unit 22 and the failure notification unit 23.

  The hot water supply control unit 21 monitors the detection flow rate of the water supply flow rate sensor 42 when the hot water supply device 1 is in an operating state, and executes the hot water supply operation when the detection flow rate of the water supply flow rate sensor 42 is equal to or greater than a predetermined operating flow rate. In the hot water supply operation, the ignition process of the burner 31 is performed, the opening of the gas flow rate adjustment valve 34 is adjusted so that the hot water supply temperature Tout becomes the target hot water supply temperature, and the heating power (heating power) of the burner 31 is adjusted. This is a process for adjusting the bypass ratio by changing the opening of the bypass ratio change valve 51. Further, in the hot water supply operation, even if the heating power of the burner 31 is maximized, if the hot water supply temperature Tout does not reach the target hot water supply temperature, the hot water supply control unit 21 restricts the supply water flow rate by the flow rate adjustment valve 41.

  Further, the hot water supply control unit 21 executes the hot water filling operation when the hot water supply device 1 is in an operating state and the remote controller 15 performs an automatic hot water filling instruction operation. The hot water filling operation is a process of supplying a set amount of hot water (set by the remote controller 15) from the hot water supply passage 2 to the bathtub 5 through the hot water filling passage 7 by opening the hot water filling valve 60. is there.

  In the hot water filling operation, the hot water supply control unit 21 changes the opening of the gas flow rate adjustment valve 34 so that the hot water filling temperature Tb becomes the target hot water filling temperature (set by the remote controller 15). While adjusting, the opening degree of the bypass ratio change valve 51 is changed, and a bypass ratio is adjusted. In the hot water filling operation, even if the heating power of the burner 31 is maximized, the hot water supply control unit 21 restricts the flow rate of the supplied water by the flow rate adjustment valve 41 when the hot water filling temperature Tb does not reach the target hot water filling temperature.

  The hot water supply control unit 21 integrates the detected flow rate of the hot water flow rate sensor 61 from the start of the hot water filling operation, and closes the hot water filling valve 60 when the integrated flow rate reaches the target hot water filling amount. The burner 31 is extinguished and the filling operation is terminated.

  The water heating prohibition unit 22 performs heat exchange by the burner 31 when the heat exchanging hot water temperature Thex or the hot water supply temperature Tout (corresponding to the temperature of the hot water supplied from the hot water supply pipe of the present invention) exceeds the high temperature determination temperature. The process which prohibits the heating (heating of the water which distribute | circulates the hot water supply path 2) of the water heater 30 is performed.

  The failure notification unit 23 determines whether or not there is a failure in the hot water supply temperature sensor 45 and the water supply temperature sensor 43 and notifies when a failure is detected.

  Next, a series of processing by the hot water supply control unit 21, the water heating prohibition unit 22, and the failure notification unit 23 will be described according to the flowchart shown in FIG.

  STEP 1 to STEP 2 and STEP 20 to STEP 21 in FIG. 2 are processes by the hot water supply control unit 21. The hot water supply control unit 21 proceeds to STEP 2 when the detected flow rate of the feed water flow rate sensor 42 becomes equal to or higher than the preset operation flow rate in STEP 1. In STEP 2, the hot water supply control unit 21 performs an ignition process of the burner 31 and starts a hot water supply operation.

  Subsequent STEP 3 to STEP 4 are processes performed by the water heating prohibition unit 22. In the judgment loop by STEP3 and STEP20, the water heating prohibition unit 22 is in STEP3, (1) the condition that the hot water supply temperature Tout is 60 ° C. (high temperature judgment temperature) or higher continues for 1 second, or (2) heat exchange It is determined whether or not a condition that the state where the hot water temperature Thex is 100 ° C. (high temperature determination temperature) or more continues for 3 seconds is satisfied. In step 20, the hot water supply control unit 21 determines whether or not the detected flow rate of the feed water flow rate sensor 42 is equal to or higher than the operating flow rate. The conditions (1) and (2) correspond to the water heating prohibition condition of the present invention.

  In STEP 20, when the detected flow rate of the water supply flow rate sensor 42 is equal to or higher than the operating flow rate, the process returns to STEP 3 and the hot water supply control unit 21 continues the hot water supply operation. On the other hand, when the detected flow rate of the water supply flow rate sensor 42 is less than the operating flow rate, the process proceeds to STEP 21, the hot water supply control unit 21 extinguishes the burner 31, ends the hot water supply operation, and returns to STEP 1.

  In STEP 3, when both the above conditions (1) and (2) are not satisfied, the process proceeds to STEP 20. When the above conditions (1) or (2) is satisfied, the process proceeds to STEP 4. move on.

  Here, when the above condition (1) or the above condition (2) is satisfied, the bypass ratio change valve 51 can be used in addition to the case where the water supply temperature sensor 43 or the hot water supply temperature sensor 45 has failed. There is a case where the water flow rate on the heat exchanger 30 side is decreased due to the stepping motor 51a out of step (a state where a deviation between the control position of the stepping motor 51a and the actual position occurs) due to dust biting or the like.

  Therefore, in STEP 4, the water heating prohibition unit 22 extinguishes the burner 31 and prohibits heating of the heat exchanger 30 by the burner 31 (heating of water flowing through the hot water supply path 2). Further, the water heating prohibition unit 22 performs initial setting of the bypass ratio change valve 51 (originating process of the stepping motor 51a).

  Subsequent STEP 5 to STEP 11 and STEP 31 to STEP 32 are processes by the failure notification unit 23. The failure notification unit 23 starts the timer in STEP 5 and proceeds to STEP 6 to determine whether or not the detected flow rate of the feed water flow rate sensor 42 is equal to or higher than the operating flow rate. When the detected flow rate of the feed water flow sensor 42 is equal to or higher than the operating flow rate, the process proceeds to STEP 7, and the failure notification unit 23 starts integrating the detected flow rates of the feed water flow sensor 42.

  The integration of the detected flow rate of the water supply flow rate sensor 42 is a range from the connection with the water supply to the location where the hot water supply temperature sensor 45 is arranged (the arrangement of the water supply temperature sensor 43) by supplying water from the water supply to the hot water supply channel 2 in STEP 9 described later. This is performed to determine that the temperature of the water in the hot water supply passage 2 is assumed to be uniform in a range from the installation location to the location where the hot water temperature sensor 45 is provided).

  In the subsequent determination loop by STEP8 and STEP9, the failure notification unit 23, in STEP8, (3) the condition that the timer has counted 15 seconds, or (4) the detected flow rate of the feed water flow rate sensor 42 is less than the operating flow rate. It is determined whether or not the condition is established. In STEP 9, the failure notification unit 23 determines that the integrated value of the detected flow rate of the water supply flow rate sensor 42 is a predetermined value (based on the volume of the hot water supply passage 2 in the range from the connection with the water supply to the location where the hot water temperature sensor 45 is provided). It is determined whether or not the above has been set.

  Here, the condition (3) is that when the waiting time from STEP 9 to STEP 10 is long because the water flow rate of the hot water supply passage 2 is small, the water temperature sensor 43 or the hot water temperature sensor after STEP 10 is used. This is for giving priority to the resumption of the hot water supply operation and returning the processing to STEP 1 rather than the determination of the presence or absence of the failure of 45.

  Further, the condition (4) is that when the user closes the hot water tap 6, the failure of the hot water temperature sensor 43 or the hot water temperature sensor 45 after STEP 10 cannot be detected, so that the next hot water supply operation is started. It is for preparing and returning a process to STEP1.

  When the condition (3) or the condition (4) is satisfied in STEP8, the process branches to STEP1, and when both the condition (3) and the condition (4) are not satisfied, the process proceeds to STEP9. When the integrated value of the detected flow rate of the water supply flow rate sensor 42 is equal to or greater than a predetermined value in STEP 9 (with water supply from the water supply to the hot water supply path 2, in the range from the connection location with the water supply to the location where the hot water temperature sensor 45 is provided When the temperature of the water in the hot water supply path 2 is assumed to be uniform), the process proceeds to STEP 10 and the failure notification unit 23 starts (restarts) the timer.

  In the next loop according to STEP 11 and STEP 31, the failure notification unit 23, in STEP 8, (5) the difference between the detected temperature of the feed water temperature sensor 43 (feed water temperature Tin) and the detected temperature of the hot water supply temperature sensor 45 (hot water supply temperature Tout) ( | Tout−Tin |, corresponding to the first temperature difference of the present invention) that is less than 15 ° C. (corresponding to the first judgment value of the present invention) for 1 second, or (6) feed water flow rate It is determined whether or not a condition that the detected flow rate of the sensor 42 is less than the operating flow rate is satisfied. In STEP 31, the failure notification unit 23 determines whether 15 seconds have elapsed from the timer.

  The condition (5) is that when the difference between the detected temperature of the feed water temperature sensor 43 and the detected temperature of the hot water temperature sensor 45 is less than 15 ° C. for one second, the feed water temperature sensor 43 and the hot water temperature sensor 45 Are both operating normally (no failure has occurred). The condition (6) is for returning the processing to STEP 1 in preparation for the start of the next hot water supply operation when the user closes the hot water tap 6.

  In STEP 11, when it is determined that the condition (5) is satisfied and both the feed water temperature sensor 43 and the hot water temperature sensor 45 are operating normally, or the condition (6) is satisfied and When preparing for the hot water supply operation, the process returns to STEP 1.

  When the condition (2) is satisfied in STEP 3 due to the step-out of the stepping motor 51a described above, the condition (5) is satisfied because the water supply temperature sensor 43 and the hot water temperature sensor 45 have not failed. Then, returning to STEP1, the prohibition of heating of the heat exchanger 30 by the burner 31 is released.

  On the other hand, when both of the conditions (5) and (6) are not satisfied in STEP 11, the process proceeds to STEP 31, and the failure notification unit 23 determines whether 15 seconds have elapsed from the timer. .

  When the timer counts 15 seconds, that is, even if 15 seconds elapses after the integrated value of the detected flow rate of the feed water flow rate sensor 42 exceeds a predetermined value in STEP 9, the detected temperature of the feed water temperature sensor 43 is detected. If the difference between the detected temperature of the hot water supply temperature sensor 45 is not less than 15 ° C., the process proceeds to STEP 32. On the other hand, when 15 seconds have not elapsed, the process returns to STEP 11.

  In STEP 32, the failure notification unit 23 displays an error code for notifying that a failure of the water supply temperature sensor 43 or the hot water supply temperature sensor 45 has occurred on the display unit of the remote controller 15 (corresponding to the first failure notification of the present invention). To do).

  As described above, according to the flowchart of FIG. 2, during the hot water supply operation, the hot water supply temperature Tout or the heat exchanger hot water temperature Thex is higher than the high temperature determination temperature in STEP 3, and the heating of the heat exchanger 30 by the burner 31 is prohibited. Using the timing, it is determined whether or not the water supply temperature sensor 43 or the hot water supply temperature sensor 45 has failed.

  Therefore, it is possible to perform a process of determining whether the water supply temperature sensor 43 or the hot water supply temperature sensor 45 is out of order without depending on the use state of the hot water supply apparatus 1 by the user. And thereby, the possibility that the state in which the feed water temperature sensor 43 or the hot water supply temperature sensor 45 has failed is lowered, and the reliability of the hot water supply apparatus 1 can be improved.

  Note that the set values of temperature and time in STEP 3, STEP 8, STEP 11, and STEP 31 are set as appropriate according to the specifications, installation conditions, operating conditions, and the like of the hot water supply device 1.

  In the present embodiment, as the water heating prohibition condition of the present invention, the condition that the hot water supply temperature Tout in (1) is 60 ° C. or higher continues for 1 second, and the hot water temperature Thex in (2) above. However, for example, a temperature sensor that detects the ambient temperature in the vicinity of the heat exchanger 30 is provided, and the detected temperature of the temperature sensor is determined to be overheated. You may use becoming more than temperature.

[Modified Embodiment]
In the above embodiment, when the detected flow rate of the water supply flow rate sensor 42 is integrated by the processing of STEP 7 to STEP 9 in FIG. 2 and the integrated value of the detected flow rate becomes a predetermined value or more, “ It is determined that the temperature of the water in the hot water supply path 2 is assumed to be uniform in the range up to the location where the temperature sensor 45 is disposed, and the water supply temperature sensor 43 or the hot water temperature sensor 45 after STEP 10 is determined. The failure detection process was performed.

  On the other hand, when the state in which the detected flow rate of the feed water flow sensor 42 is equal to or higher than the operating flow rate continues for a predetermined time or more, “ It may be determined that the temperature of the water in the path 2 has been assumed to be uniform. The predetermined time in this case is the volume of the hot water supply path 2 in the range from the place connected to the water supply to the place where the hot water supply temperature sensor 45 is provided, and the flow rate of water flow through the general hot water supply path 2 when the hot water tap 6 is opened. Etc. are set based on the above.

  In STEP 6 and STEP 8, the operating flow rate is used as the determination value to be compared with the detected flow rate of the feed water flow rate sensor 42, but a determination value other than the operating flow rate may be used.

  During the hot water filling operation, hot water having a target hot water temperature is supplied to the bathtub 5 via the hot water filling path 7 from the downstream connection point between the hot water supply path 2 and the bypass path 50. Therefore, if both hot water temperature sensor 45 and hot water temperature sensor 62 are operating normally, the detected temperature of hot water temperature sensor 45 (hot water temperature Tout) and the detected temperature of hot water temperature sensor 62 (hot water temperature Tb) Are almost identical.

  Accordingly, the failure notification unit 23 determines that the temperature difference between the hot water supply temperature Tout and the hot water filling temperature Tb (corresponding to the second temperature difference of the present invention) is equal to or greater than the second determination value during the hot water filling operation. When the hot water temperature sensor 45 or the hot water temperature sensor 62 is determined to have failed when the hot water temperature sensor 45 or the hot water temperature sensor 62 has failed, an error code indicating that the hot water temperature sensor 45 or the hot water temperature sensor 62 has failed is displayed. Alternatively, it may be displayed on the display unit of the remote controller 15. This display corresponds to the second failure notification of the present invention.

  Further, when the second failure notification has not been made before, it is assumed that both hot water temperature sensor 45 and hot water temperature sensor 62 are operating normally, and no failure of hot water temperature sensor 45 has occurred. Therefore, in the state where the second failure notification has not been made before, the condition (5) above is not satisfied in STEP 11 of FIG. 2, and when the timer counts 15 seconds in STEP 31, the hot water temperature sensor 45 Instead, there is a high possibility that the feed water temperature sensor 43 has failed.

  Therefore, in this case, the failure notification unit 23 may display an error code indicating that a failure of the water supply temperature sensor 43 has occurred on the display of the remote controller 15. This display corresponds to the third failure notification of the present invention.

  In the above embodiment, the configuration including the heat exchanger 30 and the burner 31 (gas burner) for burning the fuel gas is shown as the water heating unit of the present invention. However, the configuration is such that the heat exchanger is heated by the oil burner, the electric heater A water heating unit having another configuration such as a configuration for heating water flowing through the hot water supply path 2 may be adopted.

  Moreover, although the hot water supply apparatus 1 which has a hot water filling function was shown in this embodiment, this invention is applicable also to the hot water supply type hot water supply apparatus which does not have a hot water filling function.

  DESCRIPTION OF SYMBOLS 1 ... Hot-water supply apparatus, 2 ... Hot-water supply path, 5 ... Bathtub, 7 ... Hot water supply path, 10 ... Hot-water supply apparatus main body, 15 ... Remote control, 20 ... Controller, 21 ... Hot-water supply control 0 part, 22 ... Water heating prohibition part, 23 ... Failure notification unit, 30 ... heat exchanger, 31 ... burner, 41 ... flow rate control valve, 42 ... feed water flow rate sensor, 43 ... feed water temperature sensor, 44 ... heat exchange hot water temperature sensor, 45 ... hot water supply temperature sensor, 50 ... bypass Road, 51 ... Bypass ratio change valve, 51a ... Stepping motor, 60 ... Filling valve, 61 ... Filling flow rate sensor, 62 ... Filling temperature sensor.

Claims (3)

A water heating unit that is provided in the middle of the hot water supply path and heats the water flowing through the hot water supply path;
A water supply temperature sensor for detecting the temperature of water in the hot water supply channel upstream of the water heating unit;
A hot water supply temperature sensor for detecting the temperature of hot water in the hot water supply path downstream of the water heating unit;
A water supply flow rate sensor for detecting a flow rate of water flowing through the hot water supply path;
When a flow rate equal to or higher than a predetermined operating flow rate is detected by the water supply flow rate sensor, a hot water supply operation is performed to adjust the heating power of the water heating unit so that the detected temperature of the hot water temperature sensor becomes a target hot water supply temperature. A hot water supply control unit,
A water heating prohibition unit that prohibits heating of water flowing through the hot water supply path by the water heating unit when a water heating prohibition condition is established in which the temperature of hot water supplied from the hot water supply path becomes abnormal;
In a state where heating of the water flowing through the hot water supply passage by the water heating portion is prohibited by the water heating prohibition portion, water supply to the hot water supply passage is detected by the water supply flow rate sensor, and by water supply to the hot water supply passage, Detection of the hot water temperature sensor when the temperature of the water in the hot water supply passage between the location of the hot water temperature sensor and the location of the hot water temperature sensor is assumed to be uniform. It is determined whether or not a first temperature difference that is a temperature difference between the temperature and a temperature detected by the feed water temperature sensor is equal to or greater than a first determination value, and the first temperature difference is equal to or greater than the first determination value A hot water supply apparatus comprising: a failure notification unit that performs a first failure notification for notifying the failure of the hot water supply temperature sensor or the water supply temperature sensor. The hot water supply apparatus according to claim 1,
A bypass path that bypasses the water heating section and communicates the upstream side and the downstream side of the water heating section of the hot water supply path;
A bypass ratio change valve that is driven by a stepping motor and changes a bypass ratio that is a ratio of a flow rate of water flowing through the bypass path to a flow rate of water flowing through the water heating unit;
A water heating part hot water temperature sensor for detecting the temperature of hot water supplied from the water heating part to the hot water supply path;
The hot water temperature sensor detects the temperature of the hot water in the hot water supply channel downstream of the hot water supply channel, rather than the downstream connection point with the bypass channel,
The hot water supply control unit adjusts the heating power of the water heating unit and the bypass ratio so that the detected temperature of the hot water supply temperature sensor becomes the target hot water supply temperature,
The water heating prohibition condition is that, during execution of the hot water supply operation, the detected temperature of the hot water supply temperature sensor is equal to or higher than a first determination temperature, or the detected temperature of the water heating unit hot water temperature sensor is equal to or higher than a second determination temperature. Is, and
When the first temperature difference is less than the first determination value when the failure notifying unit prohibits heating of the water flowing through the hot water supply path by the water heating unit by the water heating prohibiting unit, A hot water supply apparatus which cancels prohibition of heating of water flowing through the hot water supply path by a water heating unit. In the hot water supply apparatus according to claim 1 or claim 2,
A hot water supply passage that communicates a location downstream of the temperature detection location of the hot water supply temperature sensor with the hot water supply passage, and a bathtub,
A hot water temperature sensor for detecting the temperature of hot water in the hot water path,
When the hot water is being supplied from the hot water supply path to the bathtub through the hot water filling path, the failure notification unit is configured to detect a temperature difference between a detected temperature of the hot water temperature sensor and a detected temperature of the hot water temperature sensor. It is determined whether or not a certain second temperature difference is greater than or equal to a second determination value. When the second temperature difference is greater than or equal to the second determination value, a failure of the hot water supply temperature sensor or the hot water temperature sensor is detected. A second failure notification is made, and when the first temperature difference is greater than or equal to the first determination value in a state where the second failure notification has not been made before, a failure of the feed water temperature sensor is notified. A hot water supply device that performs third failure notification.