JPH10213350A - Hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible for an apparatus itself to detect an abnormal state, such as a crushed bypass flow passage in automatic mode in a hot water supply device having a bypass flow passage. SOLUTION: A water supply pipe 2 of a hot water supply heat exchanger 1 is connected to a hot water supply pipe 5 with a bypass passage 12. The hot water which comes from the hot water supply heat exchanger 1 is mixed with water which comes from the bypass passage 12 with a mixing ratio control valve 13, thereby supplying hot water whose temperature is specified. A control device 10 sets a mixing ratio between hot water and water of the mixing ratio control valve 13 so that the flow rate of water flowing in the bypass flow passage 12 may be a reference flow rate ratio to a total water supply flow rate during hot water supply operation. On one hand, the reference flow rate flowing in the bypass flow passage 12, which is equivalent to the reference flow rate, is determined by computation. The determined reference flow rate and the measured bypass flow rate detected with a bypass flow rate detection sensor 15 are compared. When the measured flow rate is out of an allowable range of the reference flow rate, it is considered produce something abnormal, for example, a crushed area has been created in the bypass passage 12, thereby outputting an error signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply apparatus for heating water by burning a burner and supplying the hot water to a desired hot water supply location.

[0002]

2. Description of the Related Art FIG. 6 shows a schematic configuration of a conventional general hot water supply apparatus. In FIG. 1, a water supply pipe 2 of a water supply passage is connected to an inlet side of the hot water supply heat exchanger 1, and a water supply temperature sensor 3 for detecting a water supply temperature and a total water supply flow rate (hot water supply flow rate) are connected to the water supply pipe 2. Main flow detection sensor 4 to detect
Is provided.

[0003] A hot water supply pipe 5 functioning as a hot water supply passage is connected to the outlet side of the hot water supply heat exchanger 1, and a hot water temperature sensor 6 for detecting a tapping temperature of hot water from the hot water supply heat exchanger 1 is connected to the hot water supply pipe 5. A hot water tap 7 is provided at a hot water supply destination of the hot water supply pipe 5.

[0004] A burner 8 is provided below the hot water supply heat exchanger 1, and a combustion fan (not shown) for supplying and exhausting air is provided below the burner 8. A remote control 11 is connected to the control device 10 for controlling the hot water supply operation, and the remote control 11 is provided with a temperature setting device for setting the hot water supply temperature, a display unit for the hot water supply temperature, and the like.

[0005] The control device 10 controls the hot water supply operation as follows. When the tap 7 is opened, the main flow detection sensor 4
When a flow rate equal to or more than the operating flow rate is detected, the combustion fan is rotated to supply gas to the burner 8 and operate ignition means (not shown) to burn the burner. And
Hot water temperature detected by hot water temperature sensor 6 is controlled by remote controller 11.
The amount of gas combustion heat (gas supply amount) is controlled so as to reach the hot water supply set temperature set in the step (1), hot water at the set temperature is produced by the hot water supply heat exchanger 1, and the hot water is passed through the hot water supply pipe 5 to a desired place such as a kitchen. Supply hot water to the hot water supply location.

[0006] When the hot water is used and the tap 7 is closed, the control device 10 receives the off signal from the main flow rate detection sensor 4 and stops the combustion of the burner 8, and during the post-purge period (when the exhaust gas in the combustion chamber is exhausted). The combustion fan is stopped when the combustion fan is continuously rotated until it is discharged), and the combustion fan is stopped to prepare for the next hot water supply.

[0007]

However, when the temperature of the feed water entering the hot water supply heat exchanger 1 is low or when the set temperature of the hot water supply is low, the surface temperature of the water pipe of the hot water supply heat exchanger 1 becomes low. Then, a phenomenon occurs in which water vapor components in the exhaust gas generated by the combustion of the burner 8 touch the water pipe having a low temperature, and dew condensation occurs on the water pipe surface.

As described above, when dew is formed on the surface of the water pipe of the hot water supply heat exchanger 1, dirt and the like in the air sent from the combustion fan adhere to the dew condensation, thereby accelerating the clogging of the hot water supply heat exchanger 1. Failure occurs. In addition, components in the exhaust gas dissolve into the dew condensation, and the dew condensation takes on a strongly acidic property,
There is a problem that corrosion of the hot water supply heat exchanger 1 is accelerated and the life of the hot water supply heat exchanger 1 is shortened.

To solve the problem of the occurrence of dew condensation in the hot water supply heat exchanger 1, the applicant has developed a hot water supply system as shown in FIG. The equipment of this development is
The water supply pipe 2 and the hot water supply pipe 5 are connected and connected by a bypass passage 12, and a mixing ratio (mixing ratio) of the hot water and the water is continuously changed at a merging position of the water exiting the hot water supply heat exchanger 1 and the water exiting the bypass passage 12. A ratio adjusting valve 13 constituted by a possible motor valve or the like is provided, and the temperature of the mixed hot and cold water flowing out of the ratio adjusting valve 13 is detected by a hot water supply temperature sensor 14 as a hot water supply temperature.

In this development device, the hot water supply operation is performed by controlling the amount of combustion heat of the burner 8 by the control device 10 so that the hot water supply temperature detected by the hot water supply temperature sensor 14 becomes the hot water supply set temperature set by the remote controller 11. . According to the apparatus shown in FIG. 5, water supplied from water supply pipe 2 is supplied to hot water supply heat exchanger 1.
And a path passing through the bypass passage 12,
As the amount of water passing through the hot water supply heat exchanger 1 decreases, the temperature of hot water heated by the hot water supply heat exchanger 1 rises, and the temperature of the water pipe surface of the hot water supply heat exchanger 1 also rises, thereby causing dew condensation. Is prevented, and the conventional problem caused by the occurrence of dew condensation can be solved.

Generally, when the hot water supply of the burner 8 is stopped and the burner 8 is burned again in a short time to restart the hot water supply, a problem arises in that hot water due to the post-boiling is discharged immediately after the start of the hot water return. There is. That is, after stopping the hot water supply combustion, the amount of residual heat retained in the hot water supply heat exchanger 1 is transmitted to the retained hot water in the hot water supply heat exchanger 1, and the so-called post-boiling causes the hot water in the hot water supply heat exchanger 1 to reach a high temperature. When hot water tap 7 is opened and hot water is re-started in that state, hot water in hot water supply heat exchanger 1 and bypass passage 12
However, in the normal bypass ratio, the amount of water passing through the bypass passage opening is not enough for the boiling water to reach the set hot water temperature at the normal bypass ratio. Hot water with a hot water temperature higher than the set hot water temperature comes out of the tap 7,
A problem arises that makes the user of the hot water feel uncomfortable.

In order to solve such a problem, for example, the temperature of hot water in the hot water supply heat exchanger 1 is detected by the hot water temperature sensor 6 and the hot water in the hot water supply heat exchanger 1 is supplied to the bypass passage 12.
The mixing ratio of hot water and water for mixing hot water and hot water at a set hot water supply temperature is determined in advance in accordance with the temperature of each hot water in the hot water supply heat exchanger 1, and after the hot water supply heat exchanger 1 The mixing ratio of the hot water and the water of the ratio adjusting valve 13 is variably set according to the hot water temperature in the hot water supply heat exchanger 1 in accordance with the temperature of the boiling water and stands by, and the hot water is exchanged when the hot water is re-started. The amount of water corresponding to the temperature of the post-boiled water of the vessel 1 is supplied from the bypass passage 12,
It is conceivable to control so as to supply hot water at a hot water supply set temperature substantially eliminating post-boiling.

However, if the pipeline is crushed in the bypass passage 12 or if a component such as calcareous adheres to the inside of the bypass passage 12 due to long-term use, the influence of the after-boiling of the hot water supply heat exchanger 1 is eliminated. Even if the mixing ratio of hot water and water is calculated and set to the mixing ratio of hot water and hot water, the target amount of water cannot be obtained from the bypass passage 12 and the post-boiling at the time of returning hot water is effective. It is difficult to resolve the problem.

In addition, during the combustion operation of this type of hot water supply apparatus, the difference between the feedforward heat quantity required to raise the feed water temperature to the set hot water supply temperature and the hot water supply temperature relative to the set hot water supply temperature (the temperature detected by the hot water supply temperature sensor 14). The amount of combustion heat of the burner 8 is controlled by the total amount of heat obtained by adding the amount of feedback heat to correct the amount of heat. However, if the bypass passage 12 is crushed or if lime or the like adheres to the inside of the passage, the amount of feedback heat becomes large. For example, when the hot water temperature changes or the hot water set temperature is changed during hot water operation, the responsiveness of the combustion heat quantity control deteriorates, and the control accuracy of the hot water temperature decreases. Occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to automatically detect and notify of abnormalities as soon as possible when crushing or calcareous deposits occur in a bypass passage. Another object of the present invention is to provide a hot water supply device capable of promptly responding to the abnormality.

[0016]

In order to achieve the above object, the present invention takes the following measures. That is,
In the first invention, a water supply pipe is connected to an inlet side of the hot water supply heat exchanger, a hot water supply pipe is connected to an output side of the hot water supply heat exchanger, and the water supply pipe and the hot water supply pipe are connected by a bypass passage. The water supplied from the water supply pipe to the hot water supply heat exchanger by the combustion heating by the burner of the hot water supply heat exchanger is turned into hot water, and the hot water coming out of the hot water supply heat exchanger and the water passing through the bypass passage are mixed to set a predetermined temperature. In a hot water supply device for controlling combustion of a burner to supply hot water, a main flow rate detection sensor provided in a water supply pipe upstream of a connection portion of the bypass passage to detect a total supply flow rate, and a hot water supply sensor provided in the bypass passage. A bypass flow rate detection sensor for detecting the flow rate of the bypass passage;
A flow rate variable control means for variably controlling a flow rate flowing through the bypass passage; a data storage memory in which reference flow ratio data of a bypass passage side flow rate to a total feed water flow rate or a flow rate of the hot water supply heat exchanger side is provided; The bypass flow path side flow rate is set by the flow rate variable control means so that the reference flow rate ratio given to the bypass flow path is measured by the bypass flow rate detection sensor in the flow rate setting state and the bypass flow path determined by the reference flow rate ratio. This is a means for solving the problem with a configuration having a bypass passage abnormality detection unit that compares the reference flow rate and outputs an error signal when the measured bypass flow rate is out of a predetermined allowable range with respect to the reference flow rate. .

According to a second aspect of the present invention, in addition to the configuration of the first aspect, a time measuring means is further provided, and an actual measured bypass flow rate is out of an allowable range given in advance with respect to a reference flow rate. In some cases, an error signal is output when a time that is out of the allowable range exceeds a preset time, which is a means for solving the problem.

According to a third aspect of the present invention, in the apparatus having the structure of the first or second aspect, the bypass flow rate detection sensor is provided in the connection portion between the water supply pipe and the bypass passage instead of being provided in the bypass passage. This is provided as a means for solving the problem by being provided on the side of the passage that passes through the hot water supply heat exchanger that reaches the junction on the exit side of the bypass passage via the through-hole, and indirectly detects the flow rate that passes through the bypass passage.

[0019] In the invention having the above configuration, during hot water supply operation, the total flow rate of water supplied from the water supply pipe is detected by the main flow rate detection sensor, and the flow rate passing through the bypass passage is detected by the bypass flow rate detection sensor. Then, for example, in a stable steady state operation in which the hot water supply temperature is equal to the hot water supply set temperature, the ratio of the flow rate of the bypass passage to the total supply water flow rate or the ratio of the flow rate of the bypass passage to the flow rate of the hot water supply heat exchanger side is a reference. It is set by the flow rate variable control means so as to obtain the flow rate ratio.

In this state, the measured bypass flow rate detected by the bypass flow rate detection sensor is compared with the reference flow rate in the bypass passage calculated by the reference flow rate ratio, and the measured bypass flow rate is given in advance to the reference flow rate. When the time exceeds the allowable range or when the time out of the allowable range exceeds a preset time, an error signal is output by the bypass passage abnormality detecting unit, and the collapse of the bypass passage is prevented. An abnormality due to the adhesion of lime or the like inside the passage is automatically detected and reported by the appliance itself, and an appropriate countermeasure can be taken by reporting this error signal.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows a system configuration of the first embodiment of the hot water supply apparatus. In the system of FIG. 2, the same components as those of the system shown in FIGS. 5 and 6 are denoted by the same reference numerals, and the description thereof will not be repeated. What is characteristic in the system of this embodiment is that a bypass flow rate detection sensor 15 for directly detecting a flow rate (bypass flow rate) flowing through the bypass path 12 is provided in the bypass path 12.
5 is provided in the control device 10 to automatically detect collapse of the bypass passage 12 and adhesion abnormality such as lime in the bypass passage using the detected flow rate of FIG. Is similar to the device shown in FIG.

FIG. 1 shows a characteristic control structure of this embodiment. A combustion control unit 16, a feedback calorie deviation judging unit 17, a hot water temperature stabilizing judging unit 18, a flow rate variable control means 19, Ratio detection unit 20 and data storage memory 2
1, a bypass passage abnormality detecting unit 22, and a time measuring unit 2.
3, the bypass passage abnormality detecting section 22 includes an error determination start command section 24, a reference flow rate calculating section 25, a ratio setting section 26, a flow rate comparing section 27, and an error signal output section. And a portion 28.

[0023] The combustion control unit 16 controls the heat of combustion of the burner 8, obtained by calculation and a feedforward heat Pff and the feedback amount of heat P _FB. The feedforward heat quantity Pff is the combustion heat quantity of the burner 8 required to increase the water of the total supply flow rate detected by the main flow rate detection sensor 4 to hot water at the hot water supply set temperature set by the remote controller 11, and the feedforward heat quantity Pff is It is obtained by the following equation (1).

Pff = Q _T (T _SP −T _IN ) / η (1)

In the equation (1), Q _T is the total water supply flow rate detected by the main flow rate detection sensor 4, and T _SP is the remote control 1
The hot water supply set temperature set in 1 and T _IN is a feed water temperature sensor 3
And η indicate thermal efficiency, respectively.

The feedback heat amount P _FB is a measured hot water supply temperature (a hot water supply temperature detected by the hot water supply temperature sensor 14) T _{MIX with} respect to the hot water supply set temperature T _SP set by the remote controller 11.
Is a heat quantity that cancels the deviation of the feedback heat quantity to zero, and the feedback heat quantity P _FB is calculated by the following equation (2).

P _FB = Q _T (T _SP −T _MIX ) / η (2)

The combustion control unit 16 controls the gas supply amount to the burner 8 so that the combustion heat of the feedforward heat amount Pff is generated at the time of the ignition of the burner 8, and the feedforward heat amount Pff after the ignition of the burner 8. Then, the combustion heat amount of the burner 8 is controlled by the total heat amount obtained by adding the feedback heat amount P _FB and the feedback heat amount P _FB (by controlling the gas supply amount that generates the total heat amount to the burner 8). Further, the combustion control unit 16 determines the ratio detected by the ratio detection unit 20 when the hot water supply stability determination unit 18 determines that the measured hot water supply temperature is stable within the allowable range of the set hot water supply temperature. When the mixing ratio of hot water and water of the adjusting valve 13 is deviated from a predetermined reference flow ratio (reference ratio), the mixing ratio of hot water and water of the ratio adjusting valve 13 is adjusted by the ratio setting unit 26 and the variable flow control means 19. Set to the reference flow ratio.

The feedback calorie deviation determining unit 17 takes in the calculation result of the feedback calorie P _FB obtained by the combustion controller 16 and calculates the calculated feedback calorie P _FB from the predetermined allowable range of the feedback calorie variation. It is judged whether or not it is out of the allowable fluctuation range. If it is out of the allowable fluctuation range, it is judged to be abnormal, and if the feedback heat amount Pff is within the allowable fluctuation range, it is judged to be normal. It is added to the command section 24.

The hot water temperature stability judging section 18 fetches information on the hot water supply set temperature T _SP set by the remote controller 11 and the hot water supply temperature T _MIX detected by the hot water supply temperature sensor 14, and gives the information to the hot water supply set temperature in advance. It is determined whether or not the measured hot water supply temperature is within the allowable range of the hot water temperature fluctuation. When the measured hot water temperature is out of the allowable range, the hot water temperature is determined to be in an unstable state, and when the measured temperature is within the allowable temperature range, the hot water temperature is in a stable state. The judgment is made and the results of these judgments are added to the error judgment start command section 24 and the combustion control section 16.

The ratio detecting section 20 detects the mixing ratio of the hot water supplied from the hot water supply heat exchanger 1 and the water supplied from the bypass passage 12 based on the operation state of the ratio adjusting valve 13. The ratio adjusting valve 13 in this embodiment has a configuration in which the relationship between the control operation amount or control operation position and the mixing ratio of hot water and water clearly corresponds to each other. If the mixing ratio adjusting mechanism is of a rotation control type using a motor, the relationship between the rotation angle of the motor and the mixing ratio is determined in advance as data, and the rotation angle of the motor at the control operation position is controlled by an encoder or a volume. Is detected, the mixture ratio of hot water and water is detected.
In addition, the relationship between the operation time from the home position, which is the reference position of the motor, and the mixing ratio can be determined in advance, and the mixing ratio can be detected based on the operation direction and operation time from the home position. Further, a stepping motor may be used as the motor, and the mixing ratio may be detected based on the number of operation pulses for driving the stepping motor and the rotation angle per pulse. Ratio adjusting valve 1 by means
3. The mixing ratio of hot water and water is detected. Then, the detection result is applied to the error determination start command unit 24, the ratio setting unit 26, and the variable flow rate control unit 19.

The data storage memory 21 stores data on the ratio of the flow rate through the bypass passage 12 to the total flow rate of water supplied from the water supply pipe 2 or the flow rate between the flow rate passing through the hot water supply heat exchanger 1 and the flow rate passing through the bypass passage 12. Ratio data is stored.

The error determination start command unit 24 receives both the determination result that the hot water supply temperature is stable from the hot water temperature stability determination unit 18 and the abnormality determination result of the feedback heat amount by the feedback heat amount deviation determination unit 17. At this time, a start command for error determination is added to the reference flow rate calculation unit 25 and the ratio setting unit 26.

When the ratio setting unit 26 receives an error determination start command from the error determination start command unit 24, the mixing ratio of hot water and water of the ratio adjusting valve 13 detected by the ratio detection unit 20 is determined by the data. It is determined whether or not the reference flow ratio stored in the storage memory 21 is attained. If the detection ratio detected by the ratio detection unit 20 is not at the mixing ratio corresponding to the reference flow ratio, the flow rate variable control means 1
In step 9, the mixing ratio of the ratio adjusting valve 13 is variably controlled in a direction to correct the deviation of the mixing flow ratio so as to be the reference flow ratio.

The variable flow control means 19 receives a ratio setting command from the ratio setting section 26, controls and drives the motor of the ratio adjusting valve 13, and adjusts and sets the mixing ratio of the ratio adjusting valve 13 to the reference flow ratio.

The reference flow rate calculator 25 calculates the reference flow rate flowing through the bypass passage 12 corresponding to the reference flow rate ratio based on the data of the reference flow rate ratio stored in the data storage memory 21.

When the data storage memory 21 stores the flow ratio data of the bypass flow rate to the total feed water flow rate, for example, the ratio of the total feed water flow rate Q _T to the bypass flow rate Q _B is a: b (Q _T : Q). _{Assuming that B} = a: b), the flow rate Q _B flowing through the bypass passage 12 becomes Q _B = Q
_It is obtained by the calculation of _T × (b / a).

Further, the reference flow ratio is the ratio, for example n of the flow rate through the flow rate and the bypass passage 12 through the hot water supply heat exchanger 1 side: If given as m, the flow rate Q _B through the bypass passage Q _B = Q _T × {m / (m + n)}.

The flow rate comparing section 27 confirms from the signal of the ratio setting section 26 that the mixing ratio of the ratio adjusting valve 13 is set to be the mixing ratio corresponding to the reference flow rate ratio, The measured flow rate flowing through the bypass passage 12 detected at 15 and the reference flow rate calculating section 25
In comparing the reference flow rate Q _B of the bypass passage 12 are calculated. The flow rate comparison unit 27 is given in advance an allowable range with respect to the reference flow rate, for example, ± 0.5 liter, and the flow rate comparison unit 27 determines that the measured bypass flow rate detected by the bypass flow rate detection sensor 15 is larger than the reference flow rate. It is determined whether or not it is within a given allowable range, and a match signal is added to the error signal output unit 28 when it is within the allowable range, and a mismatch error signal is output when it is not within the allowable range.

In a normal state in which the bypass passage 12 is not crushed or calcareous adhered to the inside of the passage, the mixing ratio is set and controlled so that the ratio adjusting valve 13 has a reference flow ratio. The reference flow rate and the measured bypass flow rate should match, but if the bypass passage 12 is crushed or if lime or the like adheres inside the passage,
The reference flow rate and the measured bypass flow rate do not match. When the error signal output unit 28 receives, from the flow comparison unit 27, a mismatch error signal indicating that the measured bypass flow is out of the allowable range given with respect to the reference flow, the bypass passage 12 It determines that an abnormality such as crushing or calcification inside the passage has occurred, and outputs an error signal.

In this case, the error signal may be output immediately upon receiving the mismatch error signal from the flow rate comparison unit 27. However, the mismatch error signal may be output from the flow rate comparison unit 27 due to noise or the like. Therefore, if more safety is anticipated, a mismatch error signal is continuously output from the flow rate comparison unit 27 for a set time given in advance from the time when the mismatch error signal is added by the time measuring unit 23. It is confirmed whether or not a mismatch error signal is continuously applied until the set time elapses.
2 may be determined to have an abnormality and an error signal may be output. In this case, the reliability of the abnormality detection of the bypass passage 12 is improved.

When an error signal is output from the error signal output section 28, an error in the bypass passage 12 is displayed on a display section of the remote controller 11 based on the error signal.

The first embodiment is configured as described above. Next, the operation will be described with reference to the flowchart of FIG. First, in step 101, it is determined whether or not a flow rate (ON flow rate) equal to or greater than the operating flow rate is detected from the main flow rate detection sensor 4 after the start of the hot water supply operation. In other words, when the tap 7 is opened, the ON flow rate is detected in step 101. When the ON flow rate is not detected, the hot tap 7 is determined to be closed, and waits until the ON flow rate is detected. . When the ON flow rate is detected in step 101, the combustion of the burner 8 is started in the next step 102.

Then, in step 103, the hot water temperature detected by hot water temperature sensor 14 falls within the allowable range of hot water temperature variation given in advance with respect to the hot water set temperature set by remote controller 11, for example, ± 1 ° C. It is determined whether or not. When the hot water temperature does not fall within the allowable range of the hot water temperature fluctuation, the combustion amount control is performed in the next step 104 so that the hot water temperature becomes the set temperature.

On the other hand, when it is determined in step 103 that the hot water supply temperature is within the allowable range of the hot water temperature variation given to the set temperature, that is, it is determined that the hot water supply temperature has approached the set temperature. Then, in step 105, a timer or the like is further used to wait for the elapse of a predetermined time until the hot water supply operation state is stabilized. Then, after confirming that the time has elapsed, in step 106, the mixing ratio of hot water and water of the ratio adjusting valve 13 is changed to the reference position, that is, the mixing ratio corresponding to the reference flow ratio given to the data storage memory 21. It is determined whether or not it is.

When the mixing ratio of the ratio adjusting valve 13 is not at the reference position, the mixing ratio of hot water and water of the ratio adjusting valve 13 is controlled in the next step 107 so as to be at the reference position.

When it is determined in step 106 that the mixture ratio of the ratio adjusting valve 13 is equal to the reference ratio, in step 108, the feedback heat amount _PFB calculated by the combustion control unit 16 falls within the allowable fluctuation range. Judge whether it is in or not. When the feedback calorie is not within the fluctuation allowable range, in the next step 109, the measured bypass flow rate detected by the bypass flow rate detection sensor 15 is compared with the reference flow rate calculated by the reference flow rate calculation unit 25, and the measured bypass flow rate is compared with the reference flow rate. It is determined whether or not the flow rate is within an allowable range.

When the measured bypass flow rate is out of the allowable range given with respect to the reference flow rate, it is determined in step 110 whether or not the state continues until a preset time has elapsed. If the deviation state outside the permissible range of the measured bypass flow rate continues until the time elapses, it is determined that the bypass passage 12 has collapsed or that there is an abnormal adhesion of calcareous or the like in the bypass passage 12, and the next step At 111, an error signal is output. On the other hand, after the control of the mixing ratio of the ratio adjusting valve 13 is performed in step 107, or when it is determined that the predetermined time has not elapsed in step 105, or in step 108, the feedback heat amount falls within the allowable fluctuation range. When it is determined that the measured bypass flow rate is within the allowable range in step 109, or when it is determined that the time during which the measured bypass flow rate is out of the allowable range is within the set time in step 109, Hot water supply operation is continued in this state.

Then, while the combustion operation of the hot water supply is being performed, it is determined in step 112 whether or not the off flow rate detection signal is added from the main flow rate detection sensor 4. If the off flow rate detection signal is not added, that is, When the hot water supply combustion operation is continuing, the operation after step 103 is repeatedly performed. On the other hand, when it is detected in step 112 that the off-flow detection signal is added from the main flow detection sensor 4, that is, when it is detected that the tap 7 is closed, the combustion of the burner 8 is stopped in step 113. Stop and prepare for the next hot water supply operation.

According to this embodiment, the bypass passage 1
2 is configured to automatically detect an abnormality due to crushing or adhesion of lime or the like inside the passage and output an error signal. Therefore, the abnormality in the bypass passage 12 can be immediately recognized by the error signal. , Various measures can be taken. As a countermeasure, for example, it is possible to quickly check the abnormality of the bypass passage 12 to confirm the safety of the combustion operation. If the abnormality of the bypass passage 12 is severe, a new hot water supply device may be used. On the other hand, when the degree of abnormality of the bypass passage 12 is small, it is possible to take measures such as variably setting the amount of combustion heat lower by a predetermined amount given in advance to enhance the safety of the combustion operation.

FIG. 3 shows a system configuration of a second embodiment of the hot water supply apparatus. In the second embodiment, a continuous bypass passage 30 having no passage opening / closing valve between the water supply pipe 2 and the hot water supply pipe 5 and a bypass passage 12 having a bypass valve 31 such as a solenoid valve for opening / closing the passage are provided. The bypass passages 12 are connected to each other in parallel, and a bypass flow rate detection sensor 15 for detecting a flow rate flowing through the bypass passage 12 is provided in the bypass passage 12, and the other configuration is the same as that of the first embodiment.

In the second embodiment, the ratio adjusting valve 13 of the first embodiment is omitted, and the hot water flowing out of the hot water supply heat exchanger 1 and the hot water constantly flowing out of the bypass passage 30 and the bypass passage 12 are operated by the bypass valve 31. The mixing ratio of hot water and water is varied in two stages by two operations of the open state and the closed state of the bypass valve 31.

Also in the second embodiment, FIG.
And a circuit for automatically detecting an abnormality in the bypass passage 12 is provided. In the second embodiment, in the data storage memory 21 shown in FIG. 1, the ratio of the bypass flow rate flowing through the bypass passage 12 to the total supply water flow rate when the bypass valve 31 is opened or the bypass valve 31 is opened. In this state, data of a flow rate ratio between the flow rate through the hot water supply heat exchanger 1, the flow rate through the bypass passage 30, and the flow rate through the bypass passage 12 is stored.

Then, the ratio detecting section 20 includes a bypass valve 31
Is detected to detect the mixture ratio when the bypass valve 31 is open and when the bypass valve 31 is closed.
Then, when the bypass valve 12 is not opened when the abnormality determination of the bypass passage 12 is performed, the ratio setting unit 26 waits until the bypass valve 31 is opened, such as when the temperature of the remote controller changes or when the hot water is again supplied. .

When the bypass valve 31 is open, the reference flow rate calculating unit 25 operates the main flow rate detecting sensor 4.
The reference flow rate flowing through the bypass passage 12 is calculated based on the detection information of the total supply water flow rate detected in step (1) and the reference ratio data provided in the data storage memory 21. The flow rate comparison unit 27 compares the reference flow rate calculated by the reference flow rate calculation unit 25 with the actually measured bypass flow rate detected by the bypass flow rate detection sensor 15, and determines the allowable range where the actually measured bypass flow rate is given to the reference flow rate. Is determined, and the result is added to the error signal output unit 28.

The error signal output unit 28 receives this determination result, and when the measured bypass flow is out of the allowable range given with respect to the reference flow, immediately or by using the time measuring means 23, An error signal is output when the flow rate is outside the allowable range given for the flow rate for a set time. As a result, similarly to the first embodiment, an abnormality caused by the collapse of the bypass passage 12 or the adhesion of lime or the like inside the passage is automatically detected, and appropriate measures can be taken against the abnormality of the bypass passage. This has the same effect as the first embodiment.

It should be noted that the present invention is not limited to the above embodiments, but can adopt various embodiments. For example, in each of the above embodiments, the bypass flow rate detection sensor 15 is provided in the bypass passage 12 to directly detect the bypass flow rate flowing through the bypass passage 12. However, for example, as shown by a chain line in FIGS. A sensor 15 is provided on the side of the passage passing through the hot water supply heat exchanger 1 from the connection between the water supply pipe 2 and the bypass passage 12 to the junction of the bypass passage 12 and the hot water supply pipe 5 via the hot water supply heat exchanger 1 and the bypass passage. The bypass flow rate flowing through the filter 12 may be detected indirectly. In this case, the bypass flow rate flowing through the bypass passage 12 is indirectly calculated by subtracting the flow rate detected by the bypass flow rate detection sensor 15 from the total water supply flow rate detected by the main flow rate detection sensor 4. It is possible to ask. Further, a bypass flow rate detection sensor 15 is provided in the bypass passage 12,
A main flow rate detection sensor 4 for detecting a flow rate passing through the hot water supply heat exchanger 1 on a path from a connection between the water supply pipe 2 and the bypass passage 12 to a junction of the bypass passage 12 and the hot water supply pipe 5 via the hot water supply heat exchanger 1. May be provided. In this case, the total supply flow rate is obtained as the sum of the two flow rate sensors 4 and 15.

Further, in the above embodiment, the main flow rate detection sensor functions as the main flow rate detection section, and the bypass flow rate detection sensor functions as the bypass flow rate detection section. The flow rate detection unit may be configured to obtain the bypass flow rate and the total supply water flow rate by the unit and the flow rate detection sensor. In this case, for example, in the system shown in FIG.
_P , the detected temperature of the hot water supply temperature sensor is T _MIX , the detected temperature of the hot water supply temperature sensor 3 is T _IN , the flow rate through the hot water supply heat exchanger 1 is Q _N , the flow rate through the bypass passage 12 is Q _B , and the total water flow rate is Q _{Assuming T} , the number G is given by the following equation.

[0059] Patent number _{(G) = (T P -T} IN) × Q N / 25 = (T MIX -T IN) × Q T / 25 ··· ·· (a)

Also,

Q _T = Q _N + Q _B (b)

Therefore, T _P , T _IN , and T _MIX are detected by both equations (a) and (b), and the flow rate of one of Q _T , Q _N, and Q _B is determined. By detecting, the remaining two flow rates can be calculated and detected.
Note that the number G is obtained by detecting the valve-opening drive current of the proportional valve that controls the gas amount to the burner 8.

Further, in the above-described embodiment, the abnormality detection of the bypass passage 12 has been described as an example. However, in the system of FIG. 3, the reference flow rate that always flows through the bypass passage 30 when the bypass valve 31 is closed. By providing a value, it is possible to always detect an abnormality in the bypass passage 30 by closing the bypass valve 31.

[0064]

According to the present invention, the apparatus itself automatically detects an abnormality caused by the collapse of the bypass passage connecting the water supply pipe and the hot water supply pipe or the adhesion of lime or the like inside the passage, and immediately detects an abnormality in the bypass passage. Since the abnormality is reported by the output of the error signal, when an abnormality occurs in the bypass passage 12, it is possible to immediately recognize the abnormality and take an appropriate countermeasure. Can be increased.

In particular, when the abnormality of the bypass passage is detected during the hot water supply operation, the time during which the measured bypass flow is out of the predetermined allowable range with respect to the reference flow through the bypass passage exceeds the predetermined time. In such a configuration that an error signal is sometimes output, when an error (abnormality of the bypass passage) is instantaneously detected due to the influence of noise or the like, it is determined that the error detection is not an abnormality of the bypass passage. Since the error signal is output only when the abnormality of the bypass passage is reliable, the reliability of the abnormality detection of the bypass passage can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of each embodiment of the present invention.

FIG. 2 is an explanatory diagram of a system configuration of a first embodiment of the hot water supply apparatus.

FIG. 3 is an explanatory diagram of a system configuration of a second embodiment of the hot water supply apparatus.

FIG. 4 is a flowchart showing an operation of the first embodiment.

FIG. 5 is an explanatory diagram of a configuration of a hot water supply device proposed by the present applicant.

FIG. 6 is an explanatory diagram showing a system configuration of a conventional general hot water supply apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 hot water supply heat exchanger 4 main flow rate detection sensor 12 bypass passage 13 ratio adjustment valve 22 bypass passage abnormality detection unit 25 reference flow rate calculation unit 27 flow rate comparison unit 28 error signal output unit 31 bypass valve

Claims (3)

[Claims] A hot water supply pipe is connected to an inlet side of a hot water supply heat exchanger, a hot water supply pipe is connected to an outlet side of the hot water supply heat exchanger, and the water supply pipe and the hot water supply pipe are connected by a bypass passage. The water supplied from the water supply pipe to the hot water supply heat exchanger by the combustion heating by the burner of the hot water supply heat exchanger is turned into hot water, and the hot water flowing out of the hot water supply heat exchanger and the water passing through the bypass passage are mixed to form a hot water having a set temperature. A hot water supply device for controlling combustion of a burner to supply hot water, a main flow rate detection unit for detecting a total supply water flow rate, a bypass flow rate detection unit for detecting a flow rate of the bypass passage, and a total supply water flow rate or a hot water supply heat exchanger side. A data storage memory to which reference flow ratio data of a bypass passage side flow rate to a flow rate is provided, and the bypass flow rate detection unit detects the state of the device having the reference flow ratio provided to the data memory. A bypass passage abnormality detection unit that compares a bypass flow amount with a reference flow amount of the bypass passage obtained by the reference flow ratio, and outputs an error signal when the bypass flow amount is out of a predetermined allowable range with respect to the reference flow amount; A hot water supply device comprising: 2. A time measuring means, wherein when the bypass flow rate is out of a predetermined allowable range with respect to the reference flow rate, the time out of the allowable range exceeds a predetermined time set in advance. The hot water supply apparatus according to claim 1, wherein the hot water supply apparatus is configured to output an error signal. 3. The main flow rate detection section and the bypass flow rate detection section each detect a flow rate using a flow rate detection sensor. Instead of providing the flow rate detection sensor of the bypass flow rate detection section in the bypass passage, the water supply pipe and the bypass passage are provided. And a flow passage passing through the bypass passage and indirectly detecting a flow rate passing through the bypass passage, provided on a passage side passing through the hot water supply heat exchanger from the connection portion of the hot water supply heat exchanger to the junction on the outlet side of the bypass passage via the hot water supply heat exchanger.
Or the hot water supply apparatus according to claim 2.