JP4475170B2 - Water heater - Google Patents

Description

  The present invention relates to a water heater that can reduce after boiling.

  Conventionally, as shown in FIG. 2, this type of hot water heater is configured to exchange heat in water supplied from a water supply port by a heat exchanger 3 heated by a burner 8 or the like and raise the temperature to a predetermined temperature. The temperature is set to a set temperature by mixing with water supplied from a bypass passage formed by connecting a water supply path and a hot water supply path so as to bypass the vessel 3. A water amount detection device 2 and an incoming water temperature detection device 1 are provided in the water supply path, a bypass valve 18 is provided in the bypass passage, and a hot water temperature detection device 4 and a water solenoid valve 5 are provided in the hot water path. Is provided. The combustion amount of the burner 8 is set based on the information detected by the water amount detection device 2 and the incoming water temperature detection device 1, and the information detected by the tapping temperature detection device 4 is fed back to control the opening degree of the bypass valve 18. Thus, the distribution amount of water to the heat exchanger 3 side and the hot water side is set, and hot water having a temperature set by the external input device 12 is supplied.

  In addition, a pressure relief valve 20 is provided in the water supply path to suppress the pressure to a constant level when the pressure in the water flow path rises due to the subsequent boiling of the heat exchanger 3 or the like. The gas is supplied to the burner 8 through the original solenoid valve 6 and the gas proportional valve 7 and simultaneously mixed with the combustion air supplied from the fan 9 for combustion. A series of operations relating to this combustion is controlled by the combustion control means 24. The external input device 12 has switches 14 and 15 that can set a constant water amount, a display unit 18 that can display the constant water amount, a notification device 13 that notifies that the constant water amount has been reached, and an open / close control of the water electromagnetic valve 5. A second switch 16 that can turn on / off the function of the water electromagnetic valve control means 23 is provided. The control device 22 is configured to add water amount measuring means 25 that adds up the amount of water flowing through the water passage according to a signal from the water amount detection device 2, A water electromagnetic valve control means 23 is provided for closing the water passage by the water electromagnetic valve 5 in the water passage and informing from the alarm 13 of the external input device 12 when the water amount becomes a constant water amount set by the external input device 12.

  With this configuration, when the integrated flow rate flowing through the water passage after the start of operation reaches a certain amount of water set by the external input device 12, the water electromagnetic valve 5 of the water passage closes the water passage to stop hot water supply, and the external input device 12 When the hot water supply is used next time, the water solenoid valve 5 is opened by the second switch 16 of the external input device 12 so that it can be used.

As described above, the conventional water heater automatically stops hot water supply when the set amount of water reaches a certain level, and it does not leave hot water in the bathtub without needing to immediately close the faucet. Control is performed such that hot water can be used as soon as the second switch 16 is turned on (see, for example, Patent Document 1).
JP-A-7-35406

  However, in the conventional configuration, a constant water amount is set by the external input device 12, the water amount flowing through the water passage is integrated by the water amount measuring means 25, and the integrated total water amount reaches a constant water amount set by the external input device 12. The combustion of the burner 8 was continued, and when the water amount reached a certain level, the combustion of the burner 8 was stopped and the water passage was closed by the water electromagnetic valve 5 provided in the water passage. By closing this water passage, the temperature of the residual water in the heat exchanger 3 rises abnormally due to residual heat and becomes a boiled state, and the pressure in the water passage rises. Since this pressure increase is released to the atmosphere by the pressure relief valve 20 installed in the water supply path, the pressure in the water passage is not left in an elevated state, but when the pressure relief valve 20 opens to the atmosphere. However, there was a problem that water in the water supply path leaked out.

  In order to solve the conventional problems, a water heater of the present invention controls a heat exchanger that heats supplied water to raise the temperature, a burner that heats the heat exchanger, and combustion of the burner Combustion control means, a water amount detection device for detecting the amount of supplied water, a water amount measurement means for detecting an integrated water amount based on a signal from the water amount detection device, a water electromagnetic valve for opening and closing a water passage, and a constant water amount A water electromagnetic valve control means for controlling the water electromagnetic valve based on information of the water amount measuring means and the external input device, and a water amount that is a predetermined amount less than a constant water amount set by the external input device When the water amount measuring means accumulates, combustion of the burner is stopped by the combustion control means and the water flow is continued, and when the predetermined amount of water is reached, the water electromagnetic valve is closed and hot water supply is stopped. Also It is.

  According to the above invention, the combustion is stopped with the accumulated water amount smaller than the set constant water amount and only the water passage state is continued. Therefore, the after-boiling phenomenon is prevented by flowing water into the heat exchanger and cooling. It is possible to eliminate water leakage from the pressure relief valve by suppressing the pressure rise in the water passage.

  When supplying a set amount of hot water, the water heater of the present invention can prevent deterioration of the heat exchanger due to post-boiling, and can eliminate water leakage from the pressure relief valve.

  1st invention mixes the hot water heated by the heat exchanger heated with the burner with the water supplied via a bypass valve, adjusts it to predetermined temperature, and the fixed amount of water set with the external input device A hot water path that flows through the heat exchanger is provided with a pressure relief valve, a water amount detection device, an incoming water temperature detection device, a water electromagnetic valve, and a hot water temperature detection device, A water amount measuring means for integrating the total amount of water flowing through the hot water path by a signal of the water amount detecting device, and when the integrated value of the water amount measuring means reaches a set water amount, the water electromagnetic valve is closed and opened by an instruction from the external input device. A water electromagnetic valve control means for controlling, and a combustion control means for controlling the combustion of the burner, when the integrated value of the water amount measuring means is a predetermined amount less than a constant amount set by an external input device, Burning the burner Stopping and continuing water flow to the heat exchanger, and when the integrated value reaches a set fixed amount, the water electromagnetic valve is closed to stop water flow to the heat exchanger. Since the combustion is stopped with the accumulated water amount smaller than the set constant water amount and only the water flow state is continued, the post-boiling phenomenon is caused by cooling with flowing water while the heat exchanger is stopped. It is possible to prevent water leakage from the pressure relief valve by suppressing the pressure rise in the water passage.

  The second invention is characterized in that the larger the fixed amount set by the external input device, the combustion of the burner is stopped at a water amount with a smaller integrated value of the water amount measuring means. The longer the heating time of the heat exchanger, the longer the heating time of the burner is stopped at the timing when the integrated value less than the set water amount is detected, and the post-boiling phenomenon is reliably prevented by ensuring a long water passage time to the heat exchanger. In addition, water leakage from the pressure relief valve can be eliminated by suppressing the pressure rise in the water passage.

  According to a third aspect of the present invention, when the integrated value of the water amount measuring means becomes a predetermined amount less than a predetermined amount set by an external input device, the burner combustion amount is changed to the minimum side and the amount of water is passed to the heat exchanger. When water is continued and the integrated value reaches a set fixed amount, combustion of the burner is stopped, the water solenoid valve is closed, and water flow to the heat exchanger is stopped. Yes, the temperature of the heat exchanger is changed by continuing the water flow while suppressing the heat exchanger heating by changing the burner combustion amount to the minimum combustion amount side at the timing when the integrated water amount less than the set constant water amount is detected The after-boiling phenomenon can be prevented while gradually decreasing the pressure, and water leakage from the pressure relief valve can be eliminated by suppressing the pressure rise in the water passage.

  The fourth invention is characterized in that the larger the fixed amount set by the external input device is, the more the amount of water measured by the water amount measuring means is changed, and the burner combustion amount is changed to the minimum side. As the amount of water set increases and the heating time of the heat exchanger increases, the heat exchanger changes the combustion amount of the burner to the minimum combustion amount side at the timing when the integrated value less than the set amount of water is detected and suppresses heating of the heat exchanger By ensuring a long water passage time to the water, it is possible to reliably prevent the post-boiling phenomenon, and it is possible to eliminate water leakage from the pressure relief valve by suppressing the pressure rise in the water passage.

  5th invention mixes the hot water heated by the heat exchanger heated with the burner with the water supplied via a bypass valve, adjusts to predetermined temperature, and the fixed amount of water set with the external input device A hot water path that flows through the heat exchanger is provided with a pressure relief valve, a water amount detection device, an incoming water temperature detection device, a water electromagnetic valve, and a hot water temperature detection device, A water amount measuring means for integrating the total amount of water flowing through the hot water path by a signal of the water amount detecting device, and when the integrated value of the water amount measuring means reaches a set water amount, the water electromagnetic valve is closed and opened by an instruction from the external input device. Water electromagnetic valve control means for controlling and combustion control means for controlling the combustion of the burner, and when the integrated value of the water amount measuring means reaches a constant amount set by an external input device, the water electromagnetic valve is closed to heat Stop water flow to the exchanger After that, the water solenoid valve is opened for a certain period of time so that the water flow to the heat exchanger is restarted. By passing water to the heat exchanger in a state where combustion of the water is stopped, the post-boiling phenomenon is prevented, and water leakage from the pressure relief valve can be eliminated by suppressing the pressure rise in the water passage.

  According to a sixth aspect of the present invention, when the integrated value of the water amount measuring means reaches a certain amount set by the external input device, the water electromagnetic valve is closed to stop water flow to the heat exchanger, and then the water electromagnetic valve is turned over several times. It is characterized in that it is opened for a certain period of time and water is repeatedly passed through the heat exchanger, and a predetermined hot water supply capacity is secured until the set amount of water is discharged, and then the temperature of the heat exchanger is lowered. Accordingly, it is possible to reliably prevent the post-boiling phenomenon by repeating the opening and closing operation of the water solenoid valve, and it is possible to eliminate water leakage from the pressure relief valve by suppressing the pressure rise in the water passage.

  In the seventh invention, when the water solenoid valve is forcibly closed by an external input device to stop the hot water supply operation, the water solenoid valve is then opened for a certain period of time to allow water to flow to the heat exchanger. Even if the hot water supply operation is forcibly stopped by an external input device before reaching the set amount of water, the water solenoid valve is opened and the heat exchanger is cooled. By preventing the post-boiling phenomenon and suppressing the pressure rise in the water passage, water leakage from the pressure relief valve can be eliminated.

  The eighth invention is characterized in that the water passing operation after stopping the combustion of the burner or changing the combustion amount to the minimum side allows the water to pass only to the heat exchanger side by adjusting the bypass valve. The cooling operation of the heat exchanger is performed in a state in which water flow to the bypass passage is suppressed, effectively preventing the post-boiling phenomenon and suppressing the pressure rise in the water passage from the pressure relief valve. Water leakage can be eliminated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a water heater in Embodiment 1 of the present invention. In FIG. 1, an incoming water temperature detecting device 1 for detecting an incoming water temperature provided in a water passage, a water amount detecting device 2 for detecting the amount of water, a heat exchanger 3 for heating water, and a hot water temperature detecting device for detecting a hot water temperature. 4 and a combustion part for heating the heat exchanger 3 are constituted by a gas original solenoid valve 6, a gas proportional valve 7, a burner 8, and a combustion air fan 9, and burns based on information from each detection device. Combustion is controlled by the control means 19.

  A water electromagnetic valve 5 is provided in the water passage and is opened and closed by a predetermined signal to control water flow. Further, a water amount measuring means 21 for integrating the total amount of water flowing through the water passage by a signal of the water amount detecting device 2, first switches 14 and 15 that can set a constant water amount, and a display unit 17 that can display the constant water amount are provided. When the total amount of water integrated by the external input device 12 and the water amount measuring means 21 reaches a constant amount of water set by the external input device 12, the water electromagnetic valve 5 is controlled to close the water passage by the water electromagnetic valve 5 of the water passage. A valve control means 11 is provided, and an external input device 12 notifies that the water passage is closed by the water electromagnetic valve 5. The external input device 12 is provided with a second switch 16 that can turn on and off the function of the water electromagnetic valve control means 11.

  The water passage is provided with a pressure relief valve 20 for preventing pressure rise and a bypass passage in which the water supply side and the hot water side are communicated so as to bypass the heat exchanger 3, and the heat exchanger is provided in the bypass passage. A bypass valve 18 that distributes the amount of water on the side and the outlet side is provided.

  About the hot water heater comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  With the above-described components, the water heater of the present invention distributes the amount of water from the water inlet to the heat exchanger 3 side and the hot water side by the bypass valve 18 through the incoming water temperature detecting device 1 and the water amount detecting device 2, Heat is absorbed by the heat exchanger 3 and then mixed with water on the outlet side of the bypass valve 18 so that the hot water reaches a predetermined temperature from the outlet through the outlet temperature detector 4 and the water electromagnetic valve 5. Control is performed and the hot water is discharged. In addition, a pressure relief valve 20 is installed at the water inlet to prevent pressure in the water passage by post-boiling or the like. The gas is supplied to the burner 8 through the original solenoid valve 6 and the gas proportional valve 7, and is mixed with the air supplied by the combustion air fan 9 and burned by the combustion control means 19 for controlling the combustion. The external input device 12 includes switches 14 and 15 that can set a constant water amount, a display unit 18 that can display the constant water amount, a notification device 13, and a second switch 16 that can turn on and off the functions of the water electromagnetic valve control means 11. The control device 10 includes a water amount measuring means 21 for integrating the amount of water flowing through the water passage according to a signal from the water amount detection device 2, and when the integrated total water amount reaches a constant water amount set by the external input device 12, A water electromagnetic valve control means 11 for closing the passage and notifying from the alarm 13 of the external input device 12 is provided.

  With this configuration, when the integrated flow rate flowing through the water passage after the start of operation reaches a certain amount of water set by the external input device 12, the water electromagnetic valve 5 of the water passage closes the water passage to stop hot water supply, and the external input device 12 When the hot water supply is used next time, the water solenoid valve 5 is opened by the second switch 16 of the external input device 12 so that it can be used.

  With the configuration as described above, hot water can be supplied immediately if the second switch 16 is turned on when necessary without turning off the hot water to the bathtub or the like without immediately closing the faucet. Yes.

  However, conventionally, a constant amount of water is set by the external input device 12 and the water amount measuring means 21 for integrating the amount of water flowing through the water passage, and when the integrated total water amount reaches the constant amount of water set by the external input device 12, Although the water passage was closed by the valve 5, water leaked from the pressure relief valve 20 installed to prevent pressure due to a pressure increase caused by the subsequent boiling of the water passage by the heat exchanger 3 by closing the water passage. It had the problem of end.

  In the present embodiment, the combustion control means 19 is set at the timing of the water amount slightly before the set water amount before the set water amount is detected by the water amount measuring means 21 which sets the set water amount and integrates the total water amount flowing through the water passage. Then, the combustion operation is stopped, and then only water flow to the heat exchanger 3 is continued. When the set amount of water is reached, the water solenoid valve 5 is closed to close the water passage and stop hot water supply. With this series of operations, the heat exchanger 3 can be cooled while the set amount of water is discharged, and water leakage from the pressure relief valve 20 can be prevented by suppressing the pressure rise in the water passage due to the post-boiling phenomenon. That is, when the water amount measuring means 21 detects a water amount that is smaller than the constant water amount set by the external input device 12, the combustion of the burner 8 is first stopped, and then the water amount measuring means 21 detects the set water amount. Continue water flow only. By controlling the bypass valve 18 to be closed during this water-only operation, the temperature of the heat exchanger 3 can be lowered in a short time by passing only the heat exchanger 3. By shortening the time of this single water flow operation as much as possible, the after-boiling phenomenon of the heat exchanger 3 can be prevented without affecting the hot water supply performance.

  Further, the integrated water amount for stopping the combustion operation and starting the single water flow operation is changed according to the constant water amount set by the external input device 12, and is started at a timing when the integrated water amount is smaller as the set water amount is larger. Like that. That is, when the set water amount is large and the combustion time is long, the temperature rise of the heat exchanger 3 is also high, and the cooling period is also long. Therefore, when the set water amount is large, the combustion operation is stopped at a timing when the integrated water amount is small, and the cooling effect of the heat exchanger 3 is enhanced by performing the single water flow operation for a long time. When the set water amount is small, the integrated water amount is The combustion operation is stopped at many timings, and a short water-only operation is performed, so that the cooling effect of the heat exchanger 3 is ensured while reducing the influence on the hot water supply capacity.

(Embodiment 2)
In the second embodiment of the present invention, when the integrated value of the water amount measuring means 21 becomes a predetermined amount less than the constant amount set by the external input device 12, the combustion amount of the burner 8 is changed to the minimum side and the heat is increased. Continuing water flow to the exchanger 3 and stopping the combustion of the burner 8 and closing the water solenoid valve 5 to stop water flow to the heat exchanger 3 when the integrated value reaches a set fixed amount. This is different from the first embodiment in that the cooling operation of the heat exchanger 3 is performed while the burner 8 is burned with the minimum combustion amount. That is, the combustion is continued while reducing the combustion amount on the near side of the set water amount, and the operation to the set water amount is ensured while ensuring a certain amount of hot water supply while suppressing the temperature rise of the heat exchanger 3 to the extent that the post-boiling phenomenon does not occur. It is something that is made to do.

  According to the present embodiment, since the hot water supply operation is performed up to the set amount of water in a combustion state in which the after-boiling phenomenon does not occur, it is possible to suppress the phenomenon that cold water comes out due to the cooling operation of the heat exchanger 3 and is easy to use. It is possible to prevent deterioration of the heat exchanger and water leakage while improving the efficiency.

(Embodiment 3)
In Embodiment 3 of the present invention, when the integrated value of the water amount measuring means 21 reaches a certain amount set by the external input device 12, the water electromagnetic valve 5 is closed to stop water flow to the heat exchanger 3, and then The water solenoid valve 5 is configured to open for a certain period of time to resume water flow to the heat exchanger 3, and in the first embodiment, the conventional hot water supply operation is performed up to a set amount of water, and water is supplied after the hot water supply operation is completed. The solenoid valve 5 is opened and water is passed through the heat exchanger 3 to reduce the temperature and prevent the post-boiling phenomenon. In other words, the combustion operation is continued until the water amount set by the external input device 12 is discharged at the set hot water temperature, and then the single water flow operation to the heat exchanger 3 is performed until the temperature of the heat exchanger 3 decreases. This is to prevent an increase in pressure in the water passage.

  Further, the single operation of water flow by the opening operation of the water solenoid valve 5 after stopping the hot water supply operation can obtain the same effect even if the opening and closing operation is repeated for a short time for the purpose of attenuating the pressure in the water passage. is there.

  According to the present embodiment, since the heating operation is performed with a predetermined capacity up to the set amount of water, the hot water supply capacity can be surely ensured, and the heat exchanger is deteriorated and water leakage is improved while improving usability. Can be prevented.

(Embodiment 4)
In the fourth embodiment of the present invention, when the water electromagnetic valve 5 is forcibly closed by the external input device 12 and the hot water supply operation is stopped, the water electromagnetic valve 5 is opened for a certain period of time and then passed to the heat exchanger 3. It is configured to perform water. That is, when stopping in the middle of the normal hot water supply operation, the water electromagnetic valve 5 can be forcibly closed and stopped by operating the external input device 12, but in this case as well, the burner 8 burns simultaneously with the stop of the hot water supply operation. Will stop, and the after-boiling phenomenon of the heat exchanger 3 may occur depending on the combustion time. In order to prevent such a phenomenon, even when the operation is stopped by the external input device 12, the water electromagnetic valve 5 is opened after the operation is stopped, and the water flow alone operation to the heat exchanger 3 is performed.

  The hot water heater of the present invention can prevent deterioration of the heat exchanger due to post-boiling when supplying a set amount of hot water, and can eliminate water leakage from the pressure relief valve. Applicable in general.

The block diagram of the water heater which shows embodiment of this invention Configuration diagram of a water heater showing a conventional embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Incoming water temperature detection apparatus 2 Water quantity detection apparatus 3 Heat exchanger 4 Hot water temperature detection apparatus 5 Water solenoid valve 6 Original solenoid valve 7 Gas proportional valve 8 Burner 9 Fan 10 Control apparatus 11 Water solenoid valve control means 12 External input device 18 Bypass valve 19 Combustion control means 20 Pressure relief valve 21 Water quantity measuring means

Claims (8)

A water heater that mixes hot water heated by a heat exchanger heated by a burner with water supplied via a bypass valve to adjust the temperature to a predetermined temperature and supplies a constant amount of water set by an external input device. There,
In the hot water path flowing through the heat exchanger, a pressure relief valve, a water amount detection device, a water incoming temperature detection device, a water electromagnetic valve, and a hot water temperature detection device are disposed,
A water amount measuring means for integrating the total amount of water flowing through the hot water path by a signal of the water amount detecting device, and when the integrated value of the water amount measuring means reaches a set water amount, the water electromagnetic valve is closed and opened by an instruction from the external input device. Water electromagnetic valve control means for controlling, combustion control means for controlling the combustion of the burner,
When the integrated value of the water amount measuring means becomes a predetermined amount less than a fixed amount set by an external input device, combustion of the burner is stopped and water flow to the heat exchanger is continued, and the integrated value is A water heater in which the water solenoid valve is closed to stop water flow to the heat exchanger when a predetermined amount is set. The hot water heater according to claim 1, wherein the combustion of the burner is stopped at a water amount with a smaller integrated value of the water amount measuring means as the constant amount set by the external input device is larger. When the integrated value of the water amount measuring means becomes a predetermined amount less than a constant amount set by an external input device, the combustion amount of the burner is changed to the minimum side and water flow to the heat exchanger is continued, The hot water heater according to claim 1, wherein when the integrated value reaches a predetermined amount, combustion of the burner is stopped, the water electromagnetic valve is closed, and water flow to the heat exchanger is stopped. The water heater according to claim 3, wherein the combustion amount of the burner is changed to the minimum side with a water amount with a smaller integrated value of the water amount measuring means as the constant amount set by the external input device is larger. A hot water heater that mixes hot water heated by a heat exchanger heated by a burner with water supplied via a bypass valve to adjust the temperature to a predetermined level and supplies a constant amount of water set by an external input device. There,
In the hot water path flowing through the heat exchanger, a pressure relief valve, a water amount detection device, a water incoming temperature detection device, a water electromagnetic valve, and a hot water temperature detection device are disposed,
A water amount measuring means for integrating the total amount of water flowing through the hot water path by a signal of the water amount detecting device, and when the integrated value of the water amount measuring means reaches a set water amount, the water electromagnetic valve is closed and opened by an instruction from the external input device. Water electromagnetic valve control means for controlling, combustion control means for controlling the combustion of the burner,
When the integrated value of the water amount measuring means reaches a certain amount set by an external input device, the water solenoid valve is closed to stop water flow to the heat exchanger, and then the water solenoid valve is opened for a certain period of time to open the heat exchanger. A water heater that resumes water flow to and from. When the integrated value of the water volume measuring means reaches a certain amount set by the external input device, the water solenoid valve is closed and water flow to the heat exchanger is stopped, and then the water solenoid valve is opened for a certain period of time and heat exchange is performed several times. The water heater according to claim 5, wherein water is repeatedly passed through the water heater. 7. When the water solenoid valve is forcibly closed by an external input device to stop the hot water supply operation, the water solenoid valve is then opened for a certain period of time to allow water to flow through the heat exchanger. The water heater according to claim 1. The water flow operation after stopping the combustion of the burner or changing the combustion amount to the minimum side adjusts the bypass valve so that water flows only to the heat exchanger side. Water heater.