JP5028656B2 - Water heater abnormality detection device - Google Patents

Description

  The present invention relates to an abnormality detection device for a water heater.

  As shown in FIG. 4, the heat pump type hot water heater includes a tank unit 71 having a hot water storage tank 70 and a heat source unit 73 having a refrigerant circuit 72. In this case, the refrigerant circuit 72 is configured by connecting a compressor 74, a water heat exchanger 75, an expansion valve 77, and an evaporator 78 in this order. The tank unit 71 includes the hot water storage tank 70 and a circulation path 79, and a water circulation pump 80 and a heat exchange path 81 are interposed in the circulation path 79. In this case, the heat exchange path 81 is configured by a water heat exchanger 75. Such a heat pump type water heater is disclosed in Patent Document 1, for example.

  In the above apparatus, when the compressor 74 is driven and the pump 80 is driven (actuated), the stored water (hot water) flows out from the water intake provided at the bottom of the hot water storage tank 70 to the circulation path 79, which exchanges heat. Circulates the channel 81. At this time, the hot water is heated (boiling) by the water heat exchanger 75 and returned to the upper part of the hot water storage tank 70 from the hot water inlet. As a result, hot hot water is stored in the hot water storage tank 70.

As shown in FIG. 4, the circulation path 79 in the above apparatus supplies a hot water from the hot water storage tank 70 to the heat exchange path 81 and a hot water from the heat exchange path 81 to the hot water storage tank 70. And a hot water supply pipe 83 for the purpose. The incoming water pipe 82 includes, for example, a first pipe 82a on the tank unit 71 side, a second pipe 82b on the heat source unit 73 side, and a connection pipe 82c that connects the first and second pipes. Further, the hot water supply pipe 83 includes, for example, a first pipe 83a on the tank unit 71 side, a second pipe 83b on the heat source unit 73 side, and a connection pipe 83c that connects the first and second pipes. And in this kind of heat pump type hot water heater, the refrigerant of the heat source side unit 73 normally flows in the direction of arrow A in FIG. 4, and the hot water in the circulation path 79 on the tank unit 71 side is an arrow opposite to this arrow A direction. It is set to flow in the B direction. Thus, heat is exchanged between the low-temperature water that has entered the heat exchange path 81 and the high-temperature refrigerant, and the temperature is set to rise efficiently as the low-temperature water flows in the direction of arrow B. In addition, a water thermistor 85 that detects the temperature of the low-temperature water flowing into the heat exchange path 81 is disposed in the second pipe 82b, and the temperature of the hot water heated in the heat exchange path 81 is detected in the second pipe 83b. A hot water thermistor 86 is disposed.

  By the way, when installing this type of water heater, on the installation site, the first pipes 82a and 83a on the tank unit 71 side and the second pipes 82b and 83b on the heat source unit 73 side are connected to the connection pipes 82c and 83c, respectively. Was connected through. In this case, the connection pipes 82c and 83c often use the same pipe. For example, the connection pipe 82c connects the first pipe 82a and the second pipe 83b, and the connection pipe 83c connects the first pipe 82c and 83c. In some cases, erroneous connection (erroneous piping) for connecting the first piping 83a and the second piping 82b is performed.

  Thus, when incorrect connection (erroneous piping) is performed, the low temperature water of the lower part of the hot water storage tank 70 enters the heat exchange path 81 from the opposite direction to the normal case. Accordingly, the temperature of the incoming water thermistor 85 increases, but the temperature of the hot water thermistor 86 does not increase. For this reason, the capacity of the pump 80 will be reduced, and the hot water passing through the heat exchange path 81 will flow in the direction of the arrow A opposite to the arrow B, so that a very inefficient operation is performed. Become.

  The present invention has been made to solve the above-mentioned conventional drawbacks, and its purpose is to detect a faulty pipe during construction and to suppress the continuation of inefficient operation of the water heater. It is to provide a detection device.

Therefore, the abnormality detection device for a hot water heater of the present invention includes a hot water storage tank 3, a circulation path 12 connected to the hot water storage tank 3, and a heat exchange path 14 interposed in the circulation path 12. The exchange path 14 is heated by a heat pump heating source, and the low temperature water flowing out from the hot water storage tank 3 to the circulation path 12 is boiled, and an abnormal state of the hot water heater capable of returning to the hot water storage tank 3 is detected. a detecting apparatus for supplying, circulating path 12 of the water heater, the water inlet pipe 15 for supplying the cold water to the heat exchange passage 14, the hot water from the heat exchange passage 14 into the hot water storage tank 3 For the hot water storage tank 3, the second pipe 15b on the heat pump heating source side, and the first and second pipes 15a and 15b. Connecting pipe 15c for connecting Has, determines that the temperature of the second pipe 15b is, when higher than the reference temperature which is set based on the outside air temperature, an abnormal state caused the erroneous connection to the water inlet pipe 15 and the hot water pipe 16 It is characterized by doing.

The abnormality detection device for a hot water heater of the present invention includes a hot water storage tank 3, a circulation path 12 connected to the hot water storage tank 3, and a heat exchange path 14 interposed in the circulation path 12. The exchange path 14 is heated by a heat pump heating source, and the low temperature water flowing out from the hot water storage tank 3 to the circulation path 12 is boiled, and an abnormal state of the hot water heater capable of returning to the hot water storage tank 3 is detected. a detecting apparatus for supplying, circulating path 12 of the water heater, the water inlet pipe 15 for supplying the cold water to the heat exchange passage 14, the hot water from the heat exchange passage 14 into the hot water storage tank 3 For the hot water storage tank 3, the second pipe 15b on the heat pump heating source side, and the first and second pipes 15a and 15b. Connecting pipe 15c for connecting And is, temperature of the second pipe 15b is abnormal state when above the set reference temperature based on the feed water temperature, the erroneous connection to the water inlet pipe 15 and the hot water pipe 16 occurs to the hot water storage tank 3 It is characterized by determining that it is.

In the water heater abnormality detection device, when the operation of the water heater is started, the temperature of the tapping pipe 16 (the temperature of the hot water boiled in the heat exchange path 14 and the tapping temperature) rises. The fact that the temperature of the incoming water pipe 15 (the incoming water temperature to the heat exchange path) does not increase is utilized. That is, when the incoming water pipe 15 and the outgoing hot water pipe 16 are misconnected, the incoming water temperature rises, and conversely, the outgoing hot water temperature does not rise. For this reason, when the temperature of the 2nd piping 15b of the inflow piping 15 is higher than reference temperature, it is an incorrect piping (erroneous connection) and it determines with it being an incorrect piping. Therefore, it is possible to reliably determine erroneous piping. As a result, the water heater can be operated with good heat exchange efficiency, and the running cost of the water heater can be reduced. In addition, when the reference temperature is uniquely set, a single existing sensor may be used, so that the control configuration can be simplified, and stable determination accuracy can be maintained.

  Further, if the reference temperature is set according to the outside air temperature, the determination accuracy can be further improved.

Further, by comparing the temperature of the second pipe 15b of the incoming water pipe 15 with a reference temperature based on the temperature of the hot water supply to the hot water storage tank 3, it is possible to reliably determine an erroneous pipe as described above.

  Next, specific embodiments of the abnormality detection device for a hot water heater of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a simplified diagram of a water heater (heat pump type water heater) equipped with this abnormality detection device. The water heater includes a hot water storage tank 3, a circulation path 12 connected to the hot water storage tank 3, and this circulation path. A heat exchange path 14 interposed between the hot water storage tank 12 and the heat exchange path 14 is heated by a heat pump heating source to boil off the low-temperature water flowing out from the hot water storage tank 3 into the circulation path 12. It is possible to return to the current. The hot water stored in the hot water storage tank 3 is supplied to a bathtub or the like (not shown).

  In this case, the hot water storage tank 3 is provided with a water supply port 5 on its bottom wall and a hot water outlet 6 on its upper wall. Then, tap water is supplied from the water supply port 5 to the hot water storage tank 3, and hot hot water is discharged from the hot water outlet 6. The hot water storage tank 3 has a water intake 10 at the bottom wall and a hot water inlet 11 at the top of the side wall (peripheral wall). The water intake 10 and the hot water inlet 11 are connected to each other through the circulation path 12. It is connected. The circulation path 12 is provided with a water circulation pump 13 and a heat exchange path 14. A water supply channel 8 is connected to the water supply port 5.

  By the way, the hot water storage tank 3 is provided with four remaining hot water detectors 18a, 18b, 18c, and 18d at a predetermined pitch in the vertical direction, and a temperature detector 19a that constitutes the feed water temperature detecting means 19. Each of the remaining hot water detectors 18a and the temperature detector 19a is composed of, for example, a thermistor. The circulation path 12 is provided with a water thermistor 20 a serving as the water temperature detection means 20 upstream of the heat exchange path 14, and a hot water thermistor 21 a serving as the hot water temperature detection means 21 downstream of the heat exchange path 14. Is provided.

  The circulation path 12 includes a water inlet pipe 15 and a hot water outlet pipe 16. The water inlet pipe 15 has a first pipe 15a on the hot water storage tank 3 side where the pump 13 is interposed, and a heat source side where a water inlet thermistor 20a is interposed. It consists of a second pipe 15b and a connection pipe 15c that connects (connects) the first and second pipes 15a and 15b. The hot water discharge pipe 16 is provided with a first pipe 16a on the hot water storage tank 3 side and a hot water thermistor 21a. The heat source side second pipe 16b and a connection pipe 16c for connecting (connecting) the first and second pipes 16a and 16b. In this case, as will be described later, the connection pipes 15c and 16c are connected on site.

  The heat pump heating source includes a refrigerant circuit, and the refrigerant circuit includes a compressor 25, a water heat exchanger 26 constituting the heat exchange path 14, an electric expansion valve (decompression mechanism) 27, and an air heat exchanger ( Evaporator) 28 are connected in order. That is, the discharge pipe 29 of the compressor 25 is connected to the water heat exchanger 26, the water heat exchanger 26 and the electric expansion valve 27 are connected by the refrigerant passage 30, and the electric expansion valve 27 and the evaporator 28 are connected to the refrigerant. The evaporator 31 and the compressor 25 are connected to each other through a passage 31 and a refrigerant passage 33 in which an accumulator 32 is interposed. Thus, when the compressor 25 is driven, the water flowing through the heat exchange path 14 is heated in the water heat exchanger 26. The evaporator 28 is provided with a fan 34 that adjusts the ability of the evaporator 28.

Incidentally, the control unit of the water heater, as shown in FIG. 2, the incoming water temperature detecting means 20, a hot water temperature detector 21 output, the feedwater temperature detecting means 19, the outside air temperature detecting means 22, various data A setting unit 24 to be set, a timer unit 35, and a control unit 36 to which data (numerical values) from the detection units 19, 20, 21, 22, 35, etc. are input. In this case, as shown in FIG. 1, the incoming water temperature detecting means 20 may be constituted by the incoming water thermistor 20a, the hot water temperature detector 21 output can be configured by the hot water thermistor 21a, the feed water temperature detecting means 19 Can be constituted by a temperature detector 19 a attached to the lower part of the hot water storage tank 3. Further, the outside air temperature detection means 22 can also be constituted by a temperature detection thermistor. The control means 36 can be configured using a microcomputer, for example.

  According to the water heater configured as described above, when the compressor 25 is driven and the water circulation pump 13 is driven (actuated), the stored water (low temperature water) is drawn from the water intake 10 provided at the bottom of the hot water storage tank 3. ) Flows out and flows through the heat exchange path 14 of the circulation path 12. At this time, the hot water is heated (boiling) by the water heat exchanger 26 and returned to the upper part of the hot water storage tank 3 from the hot water inlet 11. By continuously performing such an operation, hot hot water can be stored in the hot water storage tank 3. Further, during operation, discharge pipe control is performed by adjusting the opening degree of the electric expansion valve 27 and adjusting the discharge pipe temperature of the compressor 25 to the target discharge pipe temperature. In this case, since the current electricity rate system is set at a lower price than the daytime electricity rate unit, this operation is performed at a low price in the late night hours (for example, from 23:00 to 7:00) To do.

  That is, it operates for a predetermined time from a certain time (for example, 24:00 after the start of midnight time) in the midnight time (from 23:00 to 7:00 am of the next day), and the predetermined time (midnight time end time, A boiling operation for boiling a predetermined volume of water (for example, the capacity of the hot water storage tank 3) is performed at 7 am. In addition, if the required amount of hot water per day exceeds the capacity of the hot water storage tank 3, after midnight operation, additional operation is performed in the daytime outside midnight hours to secure the required hot water amount for the day. To do. In this case, when a quantity of hot water that satisfies the capacity of the hot water storage tank 3 is boiled, if a predetermined amount (for example, 50 liters) of hot water is used and the amount of stored hot water decreases, the reduced predetermined amount The additional operation of boiling the hot water is performed, and the necessary amount of hot water for the day is ensured by performing this additional operation at least once. In these boiling operations, the operation start and operation stop are determined based on the detected values of the remaining hot water detectors 18a, 18b, 18c, 18d, the incoming water thermistor 20a, and the like.

  By the way, in the water heater shown in FIG. 1, the connection work of the connection pipes 15c and 16c is performed in the field. And when it connects normally, the 1st piping 15a, the connection piping 15c, and the 2nd piping 15b constitute the inflow piping 15, and with the 1st piping 16a, the connecting piping 16c, and the 2nd piping 16b, The hot water of low temperature flowing out from the water intake 10 at the lower part of the hot water storage tank 3 passes through the heat exchange path 14 that has flowed through the water intake pipe 15, and constitutes the hot water flowing out of the heat exchange path 14. The hot water flows through the outlet pipe 16 and is returned from the hot water inlet 11 to the hot water storage tank 3. Therefore, the incoming water thermistor 20a constituting the incoming water temperature detecting means 20 detects a low incoming water temperature, and the outgoing hot water thermistor 21a constituting the outgoing hot water temperature detecting means 21 detects a hot outgoing hot water temperature.

  However, since the connection pipes 15c and 16c are connected at the site as described above, the first pipe 15a and the second pipe 16b are connected by the connection pipe 15c, and the first pipe 16a is connected by the connection pipe 16c. May be connected to the second pipe 15b. In such a case, the low temperature hot water flowing out from the water intake 10 at the lower part of the hot water storage tank 3 flows from the first pipe 15a to the second pipe 16b via the connection pipe 15c and flows into the heat exchange path 14. Further, from the heat exchange path 14, hot hot water flows out into the second pipe 15b and flows into the first pipe 16a from the second pipe 15b through the connection pipe 16c, and hot water is stored from the first pipe 16a. It will be returned to the tank 3.

Therefore, if such an erroneous connection (false pipe) is carried out, it increases to the extent that the detected temperature of the incoming water thermistor 20a (incoming water temperature) is not considered in the normal. This is impossible if it is normally connected, and the erroneous piping can be detected (detected) by comparing the incoming water temperature with the reference temperature.

  Next, a method for determining whether or not the piping is incorrect will be described using the flowchart of FIG. First, the operation is started in step S1, and it is determined in step S2 whether or not a predetermined time has elapsed from the start of operation. Here, the predetermined time is a count time (for example, 200 to 300 seconds) of the erroneous pipe detection timer (TMP) of the timer means 35. And if predetermined time has not passed, it will wait until it will pass, and if it has passed, it will transfer to Step S3. That is, the erroneous pipe detection timer (TMP) is continuously counted and waits until a predetermined time elapses. This is because when this predetermined time has elapsed from the start of operation, a difference of a predetermined amount or more occurs between the incoming water temperature and the hot water temperature. Also in this case, if other abnormality occurrence processing is performed, it is necessary to perform interrupt processing as shown in step S12. At this time, the compressor 25 is stopped and the TMP described above is stopped as in step S9. It is necessary to reset the counter in step S1.

  In step S3, the outside air temperature is read, and in the next step S4, the reference temperature T is set based on the outside air temperature. In step S5, it is determined whether or not the incoming water temperature (DTO)> the reference temperature (T). If the incoming water temperature is higher than the reference temperature in this step S5, it is predicted that the piping is erroneous as described above, and the process proceeds to step S6, and if the incoming water temperature is low, it is determined to be normal. The process proceeds to step S7.

In step S6, the count is incremented by 1, and then the process proceeds to step S8. In step S8, it is determined whether or not the number of defect determinations (NMP) is a specified number (for example, 4 times). If less than the specified number of times in step S 8, the process returns to step S9, to stop the compressor 25, to reset the TMP, to restart the compressor 25 (compressor operation start in step S1) Become. If the specified number of times (4 times in this case) is reached in step S8, the process proceeds to step S10, the compressor 25 is stopped, and the system is down (operation of the compressor 25 is prohibited) as erroneous piping. .

  In step S7, it is determined whether the hot water has been boiled. If the water has boiled, the process proceeds to step S11 to stop the compressor 25 and reset the TMP counter to end the boiling operation. If it does not boil in step S7, it waits until it boils. In the determination shown in FIG. 3, if the incoming thermistor 20 a and the outgoing hot water thermistor 21 a are not defective and the heat pump heating source has a refrigerant circuit defrost circuit, the defrost operation (defrosting operation) is performed once after the compressor is started. ) Is not performed.

In this way, if the determination as shown in FIG. 3 is performed, erroneous piping at the time of construction can be easily detected (detected) at the time of trial operation after construction, and inefficient operation is avoided (suppressed). Can do. That is, the refrigerant in the refrigerant circuit flows in the direction of arrow A in FIG. 1, and the hot water in the circulation path 12 flows in the direction of arrow B opposite to the direction of arrow A. As a result, heat exchange is performed between the low-temperature water that has entered the heat exchange path 14 and the high-temperature refrigerant, and the temperature rises as the low-temperature water flows in the direction of arrow B, so that operation with good heat exchange efficiency can be performed. . On the other hand, if incorrect piping is performed, the hot water passing through the heat exchange path 14 will flow in the direction of arrow A opposite to arrow B. That is, the hot water passing through the heat exchange path 14 flows in the same direction as the refrigerant in the refrigerant circuit, and the operation is very inefficient.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention. For example, in the above description, the reference temperature T is determined as a function of this temperature based on the outside air temperature, but the outside temperature itself may be used as the reference temperature T. Furthermore, it is also possible to set the reference temperature uniquely without detecting the outside air temperature. In this case, it is possible to detect erroneous piping using an existing single sensor, thus simplifying the control configuration. it can. In addition to the outside air temperature, the reference temperature T can also be obtained as the temperature detected by the feed water temperature detecting means 19 or as a function of the feed water temperature. In addition, when it determines with it being abnormal, you may make it notify a user etc. by generating an alarm sound. Furthermore, in the flowchart of FIG. 3, when determining an abnormality, each determination is performed a plurality of times. Of course, it may be determined that there is an abnormality once, and the number of detection (determination) may be arbitrarily set. Can be changed. If it is performed multiple times, if it is too much, it will be wasteful even if it is definitely in an abnormal state, and it will be useless, so it will be about 4-6 times as in the above embodiment. Is preferred. Carbon dioxide gas is preferably used as the refrigerant of the water heater using this abnormality detection device, but other refrigerants such as dichlorodifluoromethane (R-12) and chlorodifluoromethane (R-22) are also used. Alternatively, an alternative refrigerant such as 1,1,1,2-tetrafluoroethane (R-134a) may be used because of problems such as ozone layer destruction and environmental pollution.

It is a simplified diagram of a water heater equipped with the abnormality detection device of the present invention. It is a simplified block diagram of the control part of the abnormality detection apparatus of the said water heater. It is a flowchart figure which shows the method of detecting the incorrect piping of the abnormality detection apparatus of the said water heater. It is a simplification figure of the abnormality detection apparatus of the conventional hot water heater.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Hot water storage tank 12 Circulation path 14 Heat exchange path 15 Inlet piping 16 Outlet piping 19 Supply water temperature detection means 20 Incoming water temperature detection means 21 Outlet hot water temperature detection means 22 Outside air temperature detection means 25 Compressor

Claims (2)

A hot water storage tank (3), a circulation path (12) connected to the hot water storage tank (3), and a heat exchange path (14) interposed in the circulation path (12), the heat exchange path ( 14) is heated by a heat pump heating source to boil low-temperature water flowing out from the hot water storage tank (3) to the circulation path (12) and return to the hot water storage tank (3). A detection device for detecting an abnormal state, in which a circulation path (12) of the water heater is provided with an inlet pipe (15) for supplying the low-temperature water to the heat exchange path (14), and the heat exchange path ( the hot water from 14) and a hot water pipe (16) to be supplied to the hot water storage tank (3), the water inlet pipe (15), a first pipe of the hot water storage tank (3) side (15a) The second pipe (15b) on the heat pump heating source side and the first and second pipes (15 ) Has a (connection pipe connecting the 15b) (15c), the temperature of the second pipe (15b) is, when higher than the predetermined reference temperature based on the outside air temperature, water inlet pipe (15 ) and hot water pipe (16) and the abnormality detecting device of a water heater misconnection and judging that the abnormal state has occurred in. A hot water storage tank (3), a circulation path (12) connected to the hot water storage tank (3), and a heat exchange path (14) interposed in the circulation path (12), the heat exchange path ( 14) is heated by a heat pump heating source to boil low-temperature water flowing out from the hot water storage tank (3) to the circulation path (12) and return to the hot water storage tank (3). A detection device for detecting an abnormal state, in which a circulation path (12) of the water heater is provided with an inlet pipe (15) for supplying the low-temperature water to the heat exchange path (14), and the heat exchange path ( the hot water from 14) and a hot water pipe (16) to be supplied to the hot water storage tank (3), the water inlet pipe (15), a first pipe of the hot water storage tank (3) side (15a) The second pipe (15b) on the heat pump heating source side and the first and second pipes (15 ) Has a (connection pipe connecting the 15b) (15c), the temperature of the second pipe (15b) is higher than the reference temperature which is set based on the water temperature to the hot water storage tank (3) Occasionally, water inlet pipe (15) and hot water pipe (16) and the abnormality detecting device of a water heater misconnection and judging that the abnormal state has occurred in.