JP2017172842A - Bath water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bath water heater capable of preventing an erroneous judgment when several temperature sensing means are compared to perform a trouble judgement.SOLUTION: A bath water heater comprises an additional boiling circulation passage of a bathtub, a hot water pouring passage branched from a hot water supply passage capable of supplying heated water supply and connected to the additional boiling circulation passage, a heat exchanger for additional boiling, a circulation pump for circulating hot water to the additional boiling circulation passage, water flow detecting means for detecting a water flow in the additional boiling circulation passage, circulation temperature detecting means arranged at an upstream side of the heat exchanger for additional boiling, and poured water temperature detecting means for detecting a temperature of hot water flowing at the hot water pouring passage. In the bath water heater, detected temperatures of the circulation temperature detecting means and the feeding hot water temperature detecting means are compared with each other during hot water pouring operation to the bathtub to perform a trouble judgement of both temperature detecting means. The water flow detecting means is arranged at a downstream side of a connecting part between the hot water pouring passage and the additional boiling circulation passage and at an upstream side of the circulation temperature detecting means so as to perform the trouble judgment when the water flow detecting means detects the water flow during the hot water pouring operation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bath water heater having a bath replenishment function, and more particularly to a bath water heater that performs failure determination of a temperature sensor that detects the temperature of hot water.

  A conventional bath hot water supply device having a bath reheating function is heated by a heat source unit while circulating a hot water in a bathtub through a recirculation circulation path by operating a circulation pump in a reheating operation. At the same time, the temperature of the hot water in the bathtub is detected, and when the detected temperature reaches the bath set temperature, the reheating operation is terminated.

  However, if a temperature sensor that detects the temperature of hot water in the bathtub detects a temperature that deviates from the correct temperature, the temperature of the hot water in the bathtub cannot be normally controlled. In particular, if the temperature is shifted so as to detect a temperature lower than the correct temperature, the hot water in the bathtub is excessively heated to a temperature higher than the bath set temperature, and the user may be burned.

  In order to prevent such a danger, Patent Documents 1 and 2 disclose bath water heaters that compare the detected temperatures of a plurality of temperature sensors provided in the bath water heater to determine a failure of the temperature sensor. This temperature sensor failure judgment is based on the bath return passage that sends the hot water from the bathtub to the heat source unit during the bath reheating operation, and the bath return passage that sends the hot water from the heat source device to the bathtub. It is performed at the time of the pouring operation and the water pouring operation in which both transports are performed to send hot water to the bathtub from both sides.

Japanese Patent No. 3800667 Japanese Patent No. 3687078

  However, the water flow resistance of one of the above-mentioned two passages connected to the bathtub may be increased depending on the installation situation of the bathtub and the piping construction situation, and the passage provided with the circulation pump tends to have high water resistance. In this case, in the bath water heaters of Patent Documents 1 and 2, hot water does not flow in a passage having high water flow resistance even if a pouring operation is performed, hot water flows only in a passage on one side, and both are not conveyed. If the temperature sensor failure determination is performed in this state, the temperature detected by the temperature sensor provided in the passage where hot water does not flow is different from the temperature detected by the temperature sensor provided in the passage where hot water flows. Even if the temperature sensor is normal, it may be erroneously determined as a failure.

  An object of the present invention is to provide a bath water heater capable of preventing erroneous determination when making a failure determination by comparing a plurality of temperature detection means.

  The bath hot water supply apparatus of the invention of claim 1 is a reheating circulation passage for a bathtub, a hot water supply passage branched from a hot water supply passage capable of supplying heated hot water and connected to the reheating circulation passage, A heat exchanger, a circulation pump for circulating hot water in the recirculation circulation passage, water flow detection means for detecting a water flow in the recirculation circulation passage, and a circulation temperature detection provided on the upstream side of the recuperation heat exchanger And a pouring temperature detecting means for detecting the temperature of the hot water flowing through the pouring passage, and comparing the detected temperatures of the circulating temperature detecting means and the pouring temperature detecting means during the pouring operation to the bathtub. In the bath hot water supply apparatus that performs failure determination of both temperature detection means, the water flow detection means is disposed on the downstream side of the connecting portion between the pouring passage and the recirculation circulation passage and on the upstream side of the circulation temperature detection means, During pouring operation Flow detecting means is characterized by performing the failure determination if you detect the water flow.

  According to a second aspect of the present invention, there is provided a hot water supply apparatus according to the first aspect, wherein the circulation pump is disposed upstream of the water flow detection means and downstream of the connection portion or the connection portion. It is characterized by that.

  According to the first aspect of the present invention, since the failure determination of the temperature sensor is not performed when the water flow is not detected, it is possible to prevent the erroneous determination of the failure of the temperature sensor due to the fact that both are not conveyed during the pouring operation. it can.

  According to the invention of claim 2, in the hot water supply apparatus of claim 1, since the circulation pump is arranged at the connecting portion between the pouring passage and the recirculation circulation passage or at the downstream side of this connection portion, the recirculation circulation passage Even if there is a risk that the water flow resistance will be high and neither of them will be transported, if the water flow is not detected, the temperature sensor will not be judged for failure. Can be prevented.

It is a schematic block diagram of a hot water supply system. It is a flowchart which shows the operation | movement at the time of pouring operation.

  Hereinafter, modes for carrying out the present invention will be described based on examples.

A hot water supply system 1 shown in FIG. 1 includes a hot water supply device 2 for supplying hot water to a hot water tap and the like, and a bath hot water supply device 3.
First, the heat source unit 4 used for both the hot water supply device 2 and the bath hot water supply device 3 will be described.
The heat source unit 4 is a gas water heater that heats hot water using combustion heat of fuel gas, and has a combustion fan 5 that supplies combustion air, and a plurality of combustion tubes that mix and burn fuel gas and air. Hot water supply burner 6 and bath burner 7, hot water supply heat exchanger 8 for heating clean water by heat exchange with combustion gas, reheating heat exchanger 9 for heating hot water in bathtub 30 by heat exchange with combustion gas, neutralization And a fuel gas supply passage 11 for supplying fuel gas to the hot water supply burner 6 and the bath burner 7.

  The hot water supply heat exchanger 8 has a hot water supply primary heat exchanger 8a that heats clean water by sensible heat of combustion gas and a hot water supply secondary heat exchanger 8b that heats clean water by latent heat of the combustion gas. The connected water supply passage 12 is connected to the hot water supply secondary heat exchanger 8b, the hot water supply passage 13 is connected to the hot water supply primary heat exchanger 8a, and the hot water supply primary heat exchanger 8a and the hot water supply secondary heat exchanger 8b are connected to the passage. It is connected by the part 8c.

  The reheating heat exchanger 9 has a bath primary heat exchanger 9a that heats hot and cold water by sensible heat of the combustion gas and a bath secondary heat exchanger 9b that heats hot and cold water by the latent heat of the combustion gas. The heat exchanger 9a and the bath secondary heat exchanger 9b are connected by a passage portion 9c.

  The combustion gas is exhausted to the outside of the heat source unit 4 after completing the heat exchange in the hot water supply heat exchanger 8 and the reheating heat exchanger 9. Moisture contained in the combustion gas is condensed by cooling in the hot water supply secondary heat exchanger 8b and the bath secondary heat exchanger 9b to become acidic drain water, and is discharged to the outside through the neutralizer 10.

Next, the water supply passage 12 will be described.
The water supply passage 12 is configured to supply clean water to the heat source unit 4, distribute the clean water by the distribution valve 14, supply the hot water to the hot water supply passage 13 via the bypass passage 17, and mix the distributed clean water and hot water. Has been. The water supply passage 12 is provided with a hot water supply amount sensor 15 that detects the amount of water supplied to the heat source unit 4 and a water supply temperature sensor 16 that detects the temperature of the clean water.

Next, the hot water supply passage 13 will be described.
The hot water supply passage 13 supplies hot water heated by the heat source unit 4 to the hot water tap 18 or the like. The hot water supply passage 13 is provided with a water amount adjustment valve 19 capable of adjusting the flow rate of hot water supplied to the hot water tap 18, and a hot water supply for detecting the temperature of the hot water flowing through the hot water supply passage 13 is located near the water amount adjustment valve 19. A temperature sensor 20 (pouring temperature detection means) is provided. A pouring passage 21 for supplying hot water from the hot water supply device 2 to the bath hot water supply device 3 branches from the water amount adjustment valve 19.

Next, the pouring passage 21 will be described.
The pouring passage 21 is provided with a pouring flow rate sensor 22, a pouring electromagnetic valve 23, and a check valve 24 on the downstream side of the water amount adjustment valve 19.

Next, the bath water heater 3 will be described.
The bath water heater 3 includes a part of the heat source device 4 (bath burner 7 and reheating heat exchanger 9 and the like), a recirculation circulation passage 32 for retreating hot water in the bathtub 30, and the hot water supply passage 13. The pouring passage 21 branched and connected to the recirculation circulation passage 32, a circulation pump 33 for circulating hot water in the recirculation circulation passage 32, and a water flow detection switch 34 (for detecting the water flow in the recirculation circulation passage 32) And a circulation temperature detection sensor 35 (circulation temperature detection means) provided on the upstream side of the reheating heat exchanger 9 in the recirculation circulation path 32. Hereinafter, the water flow detection switch 34 is referred to as a water flow SW 34.

  The recirculation circulation passage 32 has a bath return passage 32a extending from the bathtub 30 to the bath secondary heat exchanger 9b, and a bath outlet passage 32b extending from the bath primary heat exchanger 9a to the bathtub 30. A downstream end of the pouring passage 21 is connected to the bath return passage 32a, and a circulation pump 33 is interposed downstream of the connecting portion of the bath returning passage 32a and the pouring passage 21 or a connecting portion thereof. Among them, a water flow SW34 is interposed in the vicinity of the downstream side of the circulation pump 33, and a circulation temperature detection sensor 35 is interposed on the downstream side of the water flow SW34 in the bath return passage 32a.

  As described above, since the connecting portion between the bath return passage 32a and the pouring passage 21 does not exist on the downstream side of the circulation pump 33, hot water in the bathtub 30 may flow back into the pouring passage 21 when the circulation pump 33 is operated. There is no. Further, a bath hot water temperature sensor 36 is provided in the bath going passage 32b. The bath hot water temperature sensor 36 is provided in order to prevent high temperature hot water due to heating of the heat source unit 4 unintended by the user from flowing into the bathtub 30. The pouring passage 21 is provided with a water level sensor 31 capable of detecting the water level of the bathtub 30.

  The hot water supply system 1 includes a control unit 37 that controls the circulation pump 33, the electromagnetic valve, and the like based on a command from an operation remote controller 38 operated by a user and detection signals from the various sensors.

Next, the control unit 37 will be described.
The control unit 37 is based on detection signals from temperature sensors and flow sensors provided in the hot water supply system 1 in accordance with the temperature of clean water, the hot water supply set temperature set by the user using the operation remote controller 38, the bath set temperature, and the like. Then, the combustion state of the heat source unit 4 is controlled, the circulating pump 33, the pouring electromagnetic valve 23, etc. are operated to supply hot water at the hot water supply set temperature, and the temperature of the hot water in the bathtub 30 is adjusted. In addition, the control unit 37 notifies the user by display or sound of the operation remote controller 38 when any abnormality or operation error occurs in the hot water supply system 1.

  At the time of bathing operation, the circulation pump 33 and the bath burner 7 of the heat source unit 4 are operated, and hot water in the bathtub 30 is circulated through the circulation passage 32 and heated. At this time, the temperature of the hot water in the bathtub 30 is detected by the circulating temperature sensor 35, and the bath reheating operation is terminated when the detected temperature reaches the bath set temperature.

  During the pouring operation, the pouring electromagnetic valve 23 is opened to operate the hot water supply burner 6 of the heat source unit 4, and the heated tap water flows into the pouring passage 21. Further, the control unit 37 integrates the amount of hot water flowing through the pouring passage 21 based on the amount of water detected by the pouring water amount sensor 22 and supplies a predetermined amount of water to the bathtub 30. Both hot water flowing through the pouring passage 21 is conveyed and supplied to the bathtub 30 from the bath return passage 32a and the bath going-out passage 32b. Since the bath burner 7 is not operated at this time, the hot water flowing through the pouring passage 21, the bath return passage 32a, and the bath going-out passage 32b are at substantially the same temperature.

Next, the failure determination of the temperature sensor during the pouring operation will be described with reference to FIG. Si (i = 1, 2,...) Represents a step.
First, when the pouring operation is started in S1, it is determined in S2 whether or not the circulation pump 33 is operating. If the determination is Yes, the circulation pump 33 is stopped in S3 and the process proceeds to S4. If the determination is No, the process proceeds to S4.

  Next, in S4, it is determined that the water flow SW34 is OFF, that is, the water flow SW34 has not detected the water flow with the circulation pump 33 stopped. If the determination is Yes, the process proceeds to S5. If the determination is No, it is determined that the water flow SW 34 is out of order, the abnormality of the water flow SW 34 is notified in S12, and the process proceeds to S13, where the pouring operation is terminated.

  Next, in S5, the pouring electromagnetic valve 23 is opened, and the clean water heated by the heat source unit 4 is supplied to the pouring passage 21 through the hot water supply passage 13. The heated clean water flowing through the pouring passage 21 is transported in both directions and poured from the bath return passage 32a to the bathtub 30 and from the bath going passage 32b to the bathtub 30 and proceeds to S6. At this time, the bath burner 7 is not operated so that hot water is not heated in the reheating heat exchanger 9.

  Next, in S <b> 6, it is determined whether or not the water flow SW <b> 34 is ON, that is, whether or not hot water poured into the bathtub 30 is flowing toward the reheating heat exchanger 9. If the determination is Yes, the process proceeds to S7. When determination is No, it progresses to S8, and it is determined whether predetermined time (for example, 30 seconds) passed since opening the pouring solenoid valve 23. If the determination in S8 is Yes, the process proceeds to S9, and if the determination in S8 is No, the process returns to S6.

  Next, in S7, the difference between the detected temperature (pour temperature) of the hot water supply temperature sensor 20 (pour temperature detection means) and the detected temperature (circulation temperature) of the circulation temperature sensor 35 (circulation temperature detection means) is below a predetermined temperature. It is determined whether it is (for example, 2 degrees C or less). If the determination is Yes, it is determined that the hot water supply temperature sensor 20 and the circulating temperature sensor 35 are normal, and the process proceeds to S9. If the determination is No, it is determined that the hot water temperature sensor 26 or the circulating temperature sensor 20 is out of order, the process proceeds to S10, the abnormality of the temperature sensor is notified, and the process proceeds to S11. The predetermined temperature is appropriately set according to the specifications of the hot water supply system 1 and the like.

  Next, in S9, the pouring operation is performed until the integrated value of the pouring water amount detected by the pouring water amount sensor 22 reaches a predetermined water amount, and when the predetermined water amount is reached, the process proceeds to S11. The predetermined amount of water can be set by the user or the like from the operation remote controller 38.

  Next, in S11, the pouring electromagnetic valve 23 is closed, and the process proceeds to S13 to end the pouring operation.

Next, the operation and effect of the bath water heater 3 of the present invention will be described.
The bath water heater 3 of the present invention conveys both hot and cold water during the pouring operation, and compares the detected temperatures of the circulating temperature sensor 35 and the hot water temperature sensor 20 when the water flow is detected by the water flow SW 34. Since the failure determination is performed, a failure of the temperature sensor can be detected. On the other hand, when the water flow is not detected by the water flow SW 34, the temperature sensor failure determination is not performed. Therefore, both the hot water and the hot water are not conveyed during the pouring operation. When they are different, it is possible to prevent an erroneous determination that is determined as a failure of the temperature sensor.

Next, a mode in which the embodiment is partially changed will be described.
[1] The temperature sensor failure determination may be performed during a water injection operation to the bathtub 30. In this case, the heating water is not heated by the heat source unit 4, and both of the drinking water are conveyed to the bathtub 30. The temperature of clean water can also be compared with the feed water temperature sensor 16 provided in the feed water passage 12, and the faulty temperature sensor can be easily identified.
[2] In the temperature sensor failure determination, it may be compared with the temperature detected by the bath water temperature sensor 36. The detected temperatures of the three temperature sensors can be compared, and the faulty temperature sensor can be easily identified.
[3] In addition, those skilled in the art can implement the present invention in various forms with various modifications without departing from the spirit of the present invention, and the present invention includes such modifications. It is.

DESCRIPTION OF SYMBOLS 1 Hot-water supply system 2 Hot-water supply apparatus 3 Bath hot-water supply apparatus 4 Heat source machine 8 Hot-water supply heat exchanger 9 Reheating heat exchanger 12 Hot-water supply path 13 Hot-water supply path 20 Hot-water supply temperature sensor (pour-temperature detection means)
21 Pouring passage 23 Pouring solenoid valve 30 Bathtub 32 Recirculation circulation passage 32a Bath return passage 32b Bath passage passage 33 Circulation pump 34 Water flow SW (Water flow detection means)
35 Circulation temperature sensor (circulation temperature detection means)
37 Control unit 38 Operation remote control

Claims (2)

A recirculation passage for the bathtub, a hot water passage branched from the hot water supply passage capable of supplying heated water, and connected to the recirculation circulation passage, a recuperation heat exchanger, and the recirculation circulation passage A circulating pump for circulating hot water, a water flow detecting means for detecting the water flow in the reheating circulation passage, a circulation temperature detecting means provided on the upstream side of the reheating heat exchanger, and the temperature of the hot water flowing through the pouring passage Hot water temperature detecting means for detecting the hot water bath, and comparing the detected temperatures of the circulating temperature detecting means and the pouring temperature detecting means during the pouring operation to the bathtub, and making a failure determination of both temperature detecting means In the device
The water flow detection means is disposed downstream of the connecting portion between the pouring passage and the recirculation circulation passage and upstream of the circulation temperature detection means, and the water flow detection means detects the water flow during the pouring operation. The bath hot water supply device, wherein the failure determination is performed when there is. The bath water heater according to claim 1, wherein the circulation pump is arranged on the upstream side of the water flow detection means and on the downstream side of the connection part or the connection part.