JP6660722B2 - Bath water heater - Google Patents

Description

  The present invention relates to a bath water heater provided with a hot water heater and a bath heater.

BACKGROUND ART Conventionally, bath water heaters having a function of heating hot water in a bathtub have been widely used. As disclosed in Patent Document 1, for example, this bath hot water supply apparatus has passed through a hot water supply side combustion chamber including a hot water supply side heat exchanger and a hot water supply side burner that heats the heat exchanger, and a hot water supply side heat exchanger. A hot-water supply circuit (hot-water supply heating unit) including a hot-water supply pipe for discharging hot water, a bath-side combustion chamber having a bath-side heat exchanger and a bath-side burner for heating the heat exchanger, and a bath-side heat exchanger A bath circuit (bath heating unit) including a return pipe and an outgoing pipe connected between a bath and a bathtub is known. In the bath circuit, the pump burns the bath-side burner while circulating the hot-water in the bathtub with the bath-side heat exchanger, so that the hot-water in the bathtub can be heated or heated by reheating. It has become.
Further, when the heat exchanger includes a plurality of fins and a heat transfer tube penetrating these fins, as disclosed in Patent Document 2, a temperature detection device such as a thermistor for detecting the temperature of the combustion chamber in the apparatus body. There is also known a technique in which a means is provided to detect clogging between fins based on the detection result of the temperature detecting means.

JP 2013-170794 A JP 2014-240716 A

When the temperature detecting means detects clogging of the fins, it is necessary to detect an abnormality of the temperature detecting means itself such as a thermistor, and to perform a process such as stopping or prohibiting combustion when an abnormality occurs. As means for this abnormality detection, it is considered that the temperature detection value by the temperature detection means is monitored after the burner starts burning, and if the temperature detection value does not show a rising tendency, it is considered that a failure has occurred in the temperature detection means. Can be
However, since the bath-side burner is irregularly burned due to reheating of the bathtub, warming operation, or the like, the interval between the stop of combustion and the start of the next combustion is often short. In this case, since the heat from the previous combustion remains in the combustion chamber, even if the thermistor or the like is normal, the temperature detection value does not show a tendency to increase after the start of combustion of the burner, and it is determined that the thermistor has failed. The combustion of the device itself is stopped or prohibited. Therefore, the user may be inconvenienced.

  Therefore, an object of the present invention is to provide a bath water heater that accurately detects an abnormality of a temperature detecting unit and does not impair usability when a thermistor or the like is normal.

Means for Solving the Problems In order to achieve the above object, an invention according to claim 1 includes a hot water supply side burner, a hot water supply side heat exchanger that heats water passing therethrough by combustion exhaust gas of the hot water supply side burner. And a part of a circulation path formed between the bath-side burner and the bathtub in the bath-side combustion chamber, and heats hot and cold water passing through the inside by the combustion exhaust of the bath-side burner. A bath heating unit including a bath-side heat exchanger, a temperature detection unit for detecting a temperature in the bath-side combustion chamber, and monitoring of a temperature detected by the temperature detection unit to control combustion of the hot-water supply-side burner and the bath-side burner. A bath water heater comprising:
After elapse of the first determination time after the start of combustion of the bath-side burner, the controller raises the temperature in the bath-side combustion chamber obtained by the temperature detection means from the initial temperature detected before the start of combustion of the bath-side burner. First determination for determining whether or not
If it is determined in the first determination that the temperature in the bath-side combustion chamber has not risen from the initial temperature by a predetermined temperature, the temperature in the bath-side combustion chamber is reduced to the second temperature within a second determination time after the stoppage of combustion in the bath-side burner . A second determination for determining whether or not a predetermined temperature lowers from a maximum temperature detected after the first determination and before the start of counting of a second determination time ;
When the second determination determines that the temperature in the bath-side combustion chamber has not fallen from the maximum temperature by a predetermined temperature, counting is performed, and when the count reaches the predetermined number, an abnormality has occurred in the temperature detecting means. Is determined.
According to a second aspect of the present invention, in the configuration of the first aspect, when the controller determines in the second determination that the temperature in the bath-side combustion chamber is lower than the maximum temperature by a predetermined temperature, the controller sets the count to 0. It is characterized by resetting.
According to a third aspect of the present invention, in the configuration of the first or second aspect, the hot water supply-side combustion chamber and the bath-side combustion chamber are disposed adjacent to each other via a partition member, and the partition member is provided with a temperature detecting unit. Then, the combustion of the hot water supply side burner can also be detected by the temperature detecting means, and the controller makes the first determination when only the bath side burner is burning.
According to a fourth aspect of the present invention, in the configuration of the first or second aspect, the hot water supply-side combustion chamber and the bath-side combustion chamber are disposed adjacent to each other via a partition member, and the partition member is provided with a temperature detection unit. In addition, the combustion of the hot water supply side burner can be detected by the temperature detecting means, and the controller does not perform the second determination when the hot water supply side burner burns during the second determination time. I do.
According to a fifth aspect of the present invention, in the configuration according to any one of the first to fourth aspects, the predetermined number is two or more, and the controller determines in the first determination that the inside of the bath-side combustion chamber is less than the predetermined number. When it is determined that the temperature has risen by a predetermined temperature from the initial temperature , the count is reset to 0.

According to the first aspect of the present invention, it is possible to accurately detect the abnormality of the temperature detection means, and to greatly reduce the erroneous detection of the intermediate failure caused by the residual heat in the bath-side combustion chamber. Therefore, when the temperature detecting means is normal, the usability of the user is not impaired.
According to the second aspect, in addition to the effect of the first aspect, it is possible to improve the detection accuracy by eliminating accidental abnormality detection.
According to the third and fourth aspects of the present invention, in addition to the effects of the first or second aspect, it is possible to prevent an error from being made in the abnormality determination due to the influence of heat from the hot water supply side combustion chamber accompanying the combustion of the hot water supply side burner. Can be prevented.
According to the fifth aspect of the invention, in addition to the effect of any one of the first to fourth aspects, the abnormality of the temperature detecting means is determined only when the first and second determinations are determined to be abnormal two or more consecutive times. Therefore, the reliability of the abnormality determination can be further improved.

It is a schematic circuit diagram of a bath water heater. It is explanatory drawing of a combustion chamber part. It is a flowchart of an intermediate failure detection control.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic circuit diagram of a bath water heater. The bath water heater 1 has a hot water supply side burner 5, 5... In a hot water supply side combustion chamber 4, a primary heat exchanger 6 as a hot water supply side heat exchanger, and a secondary heat exchanger. A hot water supply heating unit 2 that is provided with a heat exchanger 7 to heat tap water and supplies hot water, and a bath-side burner 21 and a bath-side heat exchanger 22 in a bath-side combustion chamber 20 are used for additional cooking of a bath. And a bath heating unit 3.
First, in the hot water supply heating unit 2, an inlet of the secondary heat exchanger 7 is connected to a water supply pipe 8 having a hot water supply amount sensor 9 for supplying tap water from a water supply system, and an outlet of the secondary heat exchanger 7 is connected to the primary heat exchanger. A connecting pipe 10 for supplying hot water heated by the secondary heat exchanger 7 to the primary heat exchanger 6 is connected between the inlet of the exchanger 6 and the hot water supply thermistor at the outlet of the primary heat exchanger 6. 12 is connected to a tapping pipe 11 for tapping hot water heated by the primary heat exchanger. 13 is a hot water tap.

  In the hot water supply side combustion chamber 4, the primary heat exchanger 6 is disposed upstream of the combustion exhaust path of the hot water supply burner 5, and the secondary heat exchanger 7 is disposed downstream of the combustion exhaust path. The water in the heat pipe is exchanged with the combustion exhaust. A gas pipe 14 for supplying gas to the hot water supply side burner 5 has a gas source electromagnetic valve 15, a hot water supply gas proportional control valve 16 from the upstream side, and a hot water supply switching electromagnetic valve 17, 17 for each branch pipe to each hot water supply burner 5.・ ・ Are provided respectively. Below the hot-water supply combustion chamber 4, a fan 18 for supplying combustion air to each hot-water supply burner 5 and a bath-side burner 21 is provided. Reference numeral 19 denotes an ignition igniter.

  On the other hand, in the bath heating unit 3, a return pipe 24 provided with a circulation pump 25 and a bath thermistor 26 and an outgoing pipe 27 are connected between the bath-side heat exchanger 22 and the bathtub 23. The return pipe 24 is connected to a dropping pipe 28 branched from the tapping pipe 11 and provided with a hot water supply solenoid valve 29 and a dropping water amount sensor 30, and the hot water supply solenoid valve 29 provided on the dropping pipe 28 is opened. The hot water heated by the hot water supply heating unit 2 can be supplied to the bathtub 23. A switching solenoid valve 31 is provided in a branch pipe from the gas pipe 14 connected to the bath-side burner 21. Reference numerals 32 and 33 denote check valves provided on the downstream side of the hot water supply solenoid valve 29 in the dropping pipe 28, and open and close the return pipe 24 on the return pipe 24 on the upstream side of a connection portion with the dropping pipe 28. A control motor 34 for driving possible valve bodies is provided. 35 is a controller, 36 is a hot water supply remote controller, and 37 is a bath remote controller.

FIG. 2 is an explanatory view of a combustion chamber portion. Here, a vertical partition member 41 is provided in a can body 40, and the hot water supply side combustion chamber 4 and the bath side combustion chamber 20 are formed adjacent to each other. The hot water supply side combustion chamber 4 is provided with a hot water supply side burner 5, a primary heat exchanger 6, and a secondary heat exchanger 7 (omitted in FIG. 2) in this order from below. A bath-side burner 21 and a bath-side heat exchanger 22 are provided in this order. Are fins provided in each of the heat exchangers 6 and 22 and are stacked in plural numbers at predetermined intervals in the front-rear direction (the direction perpendicular to the plane of FIG. 2), and 43 is a meandering penetrating fin 42. An air supply chamber 44 to which combustion air is supplied from the fan 18 is formed below the two burners 5 and 21.
A combustion chamber thermistor 45 is provided between the two burners 5 and 21 and the heat exchangers 6 and 22 in the partition member 41 as temperature detecting means for detecting the temperature in the combustion chambers 4 and 20. .

In the bath water heater 1 configured as described above, first, normal hot water is supplied as follows.
When the hot water tap 13 provided on the tapping pipe 11 is opened and water is passed through the appliance, and the hot water is detected by the hot water supply amount sensor 9, the controller 35 rotates the fan 18 for a predetermined time to perform hot water combustion. The combustion exhaust gas stored in the chamber 4 and the bath-side combustion chamber 20 is discharged (prepurge). Thereafter, the gas source electromagnetic valve 15 of the gas pipe 14 and each hot water supply switching electromagnetic valve 17 are opened, and the hot water supply gas proportional control valve 16 is opened at a predetermined opening to supply gas to each hot water supply side burner 5 and The igniter 19 is operated to ignite the hot water supply side burners 5, 5,.

  Then, the combustion exhaust gas of the hot water supply side burner 5 first passes through the primary heat exchanger 6 and exchanges heat with water passing through the heat transfer tubes, and then passes through the secondary heat exchanger 7 to exchange heat with water passing through the heat transfer tubes. And is discharged outside. Thereby, the sensible heat is recovered in the primary heat exchanger 6 and the latent heat is recovered in the secondary heat exchanger 7, and the heated hot water is discharged from the hot water tap 13.

  The controller 35 monitors the hot water temperature by the hot water supply thermistor 12 of the hot water pipe 11, and controls the opening and closing of the hot water supply switching electromagnetic valve 17 and the hot water supply so that the hot water temperature becomes the set temperature instructed by the hot water remote control 36 or the bath remote control 37. The opening degree of the gas proportional control valve 16 is adjusted, and the air amount is continuously changed by controlling the rotation speed of the fan 18. When the hot-water tap 13 is closed, the controller 35 confirming that the signal of the hot-water supply amount sensor 9 has stopped shuts off the gas source electromagnetic valve 15 and the hot-water supply switching electromagnetic valve 17, extinguishes the hot-water supply burner 5, and rotates the fan 18 for a predetermined time ( Post purge).

On the other hand, when the automatic switch of the hot water supply remote control 36 or the bath remote control 37 is pressed in the bath heating unit 3, the controller 35 opens the hot water supply electromagnetic valve 29 of the dropping pipe 28 to allow the hot water supply heating unit 2 to pass water and supply hot water. The side burner 5 is burned. Hot water from the tapping pipe 11 is supplied to the bathtub 23 through the dropping pipe 28 and the return pipe 24. At this time, the flow path of the return pipe 24 is opened by the control motor 34. When the amount of water detected by the drop water amount sensor 30 provided in the drop pipe 28 reaches the set water amount, the hot water supply electromagnetic valve 29 is closed to stop water supply, and the hot water supply side burner 5 is extinguished.
Next, the circulation pump 25 is operated to circulate the hot water in the bathtub 23 in the bath heating unit 3. At this time, the temperature of the hot water is monitored by a bath thermistor 26 provided in the return pipe 24, and when the temperature is equal to or lower than a set temperature, the bath-side burner 21 is ignited. Therefore, bath circulating water circulating between bath heat exchanger 22 and bathtub 23 is heated to the set temperature. When the temperature reaches the set temperature, the combustion of the bath-side burner 21 is stopped, and the circulation pump 25 is stopped.

  When the combustion products adhere between the fins 42 of the heat exchangers 6 and 22 and the fins 42 are clogged, air from the fan 18 can pass between the fins 42 and 42. The temperature of the combustion chambers 4 and 20 rises, and the combustion chamber thermistor 45 is overheated. When the detected temperature of the combustion chamber thermistor 45 reaches the set temperature in this way, the controller 35 stops the combustion of both burners 5 and 21 assuming that the fin has clogged.

At the same time, the controller 35 monitors the detected temperature of the combustion chamber thermistor 45 during the automatic operation of the bath heating unit 3 and detects an intermediate failure of the combustion chamber thermistor 45 (the output (resistance value) does not change regardless of overheating of the heat-sensitive part). Intermediate fault detection control for detecting a fault). Hereinafter, the intermediate failure detection control will be described with reference to the flowchart of FIG.
First, in S1, it is determined whether or not the hot water supply side burner 5 is burning. Here, if the hot water supply side burner 5 is burning, that is, if the hot water supply heating unit 2 is in use, the failure detection is not performed.
If the hot-water supply burner 5 is not burning, the initial temperature T ₀ of the bath-side combustion chamber 4 is detected by the combustion chamber thermistor 45 in S2, and in S3, the combustion of the bath-side burner 21 is started by additional heating or the like. It is determined whether it has been performed. Here, if the start of combustion of the bath-side burner 21 is confirmed, a first timer, which counts up for a first predetermined time (for example, 180 seconds), is started in S4.

If the stop of combustion of the bath-side burner 21 is confirmed in S6 before the first timer times out in S5, the process returns to S1 and processing is again performed from confirmation of combustion of the hot-water supply burner 5.
When the first timer times up in S5, in S7, the first determination temperature _{T 1} of the bath side combustion chamber 20 is detected by the combustion chamber thermistor 45, in S8, the first from the initial temperature _{T 0} determined temperatures _{T 1} It is determined whether the temperature has risen by 5 ° C. or more (first determination). Here, if a temperature rise of 5 ° C. or more can be confirmed, the count of the number of preliminary determinations is reset to 0 in S9, and then the process returns to S1 after waiting for the stoppage of combustion of the bath-side burner 21 in S10.
On the other hand, if the temperature rise is less than 5 ° C. in S8, the temperature in the bath-side combustion chamber 20 is continuously detected by the combustion chamber thermistor 45, and the maximum temperature T _M is stored in S11.

Next, if it is confirmed in S12 that the combustion of the bath-side burner 21 has stopped, in S13-1 , a second timer that times up for a second predetermined time (for example, 180 seconds) is started, and in S13-2, detecting a second judgment temperature T ₂ of the bath side combustion chamber 20 by combustion chamber thermistor 45. In addition, if the combustion of the hot water supply side burner 5 or the bath side burner 21 is confirmed in the determination of S14 during the counting of the second timer, the counting is canceled and the process returns to S1. If the combustion is stopped, it is determined in S15 whether or not the difference (decreased temperature) between the maximum temperature T _M obtained in S11 and the second determination temperature T ₂ is 5 ° C. or more (second). Judgment). Here, when a decrease of 5 ° C. or more is confirmed, the combustion chamber thermistor 45 is determined to be normal, the count of the number of preliminary determinations is reset to 0 in S16, the count of the second timer is canceled, and the process returns to S1. S15 at 5 ° C. without checking the decrease in the above, but before time is up in S17, detects a second judgment temperature _{T 2} again returns to S13-2.

Then, if the second timer times out in S17 without confirming a temperature decrease of 5 ° C. or more in S15, the number of preliminary determinations is counted once in S18. That is, if the temperature detected by the combustion chamber thermistor 45 does not increase by 5 ° C. or more during the combustion of the bath-side burner 21 and does not decrease by 5 ° C. or more after the combustion of the bath-side burner 21 is stopped, the number of preliminary determinations is counted. become. Next, in S19, it is determined whether or not the number of preliminary determinations is less than six. If the number of preliminary determinations is less than six, the process returns to S1.
On the other hand, if the number of preliminary determinations reaches six in the determination of S19, it is determined that an intermediate failure has occurred in the combustion chamber thermistor 45, and the combustion of the hot water supply side burner 5 and the bath side burner 21 is prohibited in S20. At the same time, an error display of a predetermined code is performed on the display units of the hot water supply remote controller 36 and the bath remote controller 37, and the number of preliminary determinations is reset to zero. Therefore, the user can know the occurrence of the trouble by prohibiting the combustion and displaying the error on the remote controller.

  As described above, according to the bath combustion device 1 of the above embodiment, the controller 35 obtains the bath side obtained by the combustion chamber thermistor 45 after the elapse of the first determination time (first timer) after the start of combustion of the bath side burner 21. A first determination (S8) for determining whether the temperature in the combustion chamber 20 has increased by a predetermined temperature (here, 5 ° C.), and the temperature in the bath-side combustion chamber 20 has increased by the predetermined temperature in the first determination. If it is determined that the temperature is not present, the temperature in the bath-side combustion chamber 20 is reduced by a predetermined temperature (here, 5 ° C.) within a second determination time (second timer) after the combustion of the bath-side burner 21 is stopped. A second determination (S15) is performed to determine whether the temperature in the bath-side combustion chamber 20 has not fallen by the predetermined temperature in the second determination (S18). The number of judgments is a predetermined number (here Is reached six times), it is determined that an abnormality has occurred in the combustion chamber thermistor 45, so that the abnormality in the combustion chamber thermistor 45 can be accurately detected, and an intermediate failure caused by residual heat in the bath-side combustion chamber 20 can be detected. False detection can be significantly reduced. Therefore, when the combustion chamber thermistor 45 is normal, the usability of the user is not impaired.

In particular, here, when the controller 35 determines in the second determination that the temperature in the bath-side combustion chamber 20 has decreased by a predetermined temperature, the controller 35 resets the count of the number of preliminary determinations to 0, thereby It is possible to improve the detection accuracy by eliminating the abnormality detection.
Further, the controller 35 performs the first determination when only the bath-side burner 21 is burning, and does not perform the second determination when the hot-water supply-side burner 5 burns during the second determination time. It is possible to prevent the error determination from being erroneous due to the influence of the heat from the hot water supply side combustion chamber 4 accompanying the combustion of the hot water supply side burner 5.
Further, assuming that the number of preliminary determinations for abnormality is 6, the controller 35 determines that the temperature in the bath-side combustion chamber 20 has increased by a predetermined temperature in the first determination when the count of the number of preliminary determinations is less than six. In this case, by resetting the count of the number of preliminary determinations to 0, the abnormality of the combustion chamber thermistor 45 is determined only after the first and second determinations are determined to be abnormal six times in succession. Properties can be further improved.

The temperature rise and fall of the first and second determinations are not limited to 5 ° C., but can be increased or decreased as appropriate. The number of preliminary determinations is not limited to six, and may be appropriately increased or decreased. However, it is also possible to set the number of preliminary determinations to one, and immediately determine that an abnormality has occurred if the first and second determinations do not confirm a rise in temperature and a decrease in temperature.
In the above embodiment, the number of preliminary determinations is reset to 0 if the temperature increase of 5 ° C. or more can be confirmed in the first determination and the temperature decrease of 5 ° C. or more in the second determination. May be carried over and the subsequent monitoring may be continued.
Further, the notification after the abnormality determination is not limited to the error display on the remote controller, but may be replaced with an electronic sound or a synthesized voice, or may be used in combination. Burning of the burner may be prohibited in consideration of ease of use, and may be performed a plurality of times after the abnormality is determined or after permitting combustion for a predetermined time, or only the bath burner, not all burners, may be prohibited. Can also.

  In the above embodiment, the hot water supply heating section includes the primary heat exchanger and the secondary heat exchanger as the hot water supply side heat exchangers, but has no secondary heat exchanger and has only the primary heat exchanger. It does not matter. The bath heating section may also include a primary heat exchanger and a secondary heat exchanger as bath-side heat exchangers.

  1. Bath water heater, 2. Hot water heater, 3. Bath heater, 4. Hot water combustion chamber, 5. Hot water burner, 6. Primary heat exchanger, 7. Secondary heat Exchanger, 8 ... water supply pipe, 11 ... hot water pipe, 20 ... bath-side combustion chamber, 21 ... bath-side burner, 22 ... bath-side heat exchanger, 23 ... bathtub, 24 ... return pipe, 27. Outgoing piping, 35. Controller, 36. Hot water supply remote control, 37 .. Bath remote control, 40 .. Can body, 41 .. Partitioning member, 45 .. Combustion chamber thermistor.

Claims (5)

A hot-water supply heating unit including a hot-water supply-side burner and a hot-water supply-side heat exchanger that heats water passing therethrough by combustion exhaust gas of the hot-water supply-side burner;
The bath-side combustion chamber includes a bath-side burner and a bath-side heat exchanger that is a part of a circulation path formed between the bathtub and heats hot and cold water passing through the inside by the combustion exhaust gas of the bath-side burner. Bath heating section,
Temperature detection means for detecting the temperature in the bath-side combustion chamber,
A controller for monitoring a temperature detected by the temperature detecting means, and a controller for controlling combustion of the hot water supply side burner and the bath side burner,
The controller is configured such that after a first determination time elapses after the start of combustion of the bath-side burner, the temperature in the bath-side combustion chamber obtained by the temperature detecting means is an initial temperature detected before the start of combustion of the bath-side burner. A first determination for determining whether or not a predetermined temperature rise from
If it is determined in the first determination that the temperature in the bath-side combustion chamber has not risen from the initial temperature by a predetermined temperature, within the second determination time after the stoppage of combustion in the bath-side burner, the temperature in the bath-side combustion chamber is reduced. A second determination for determining whether or not the temperature is lower by a predetermined temperature from the maximum temperature detected before the start of the counting of the second determination time after the first determination ;
Counting the number of times when it is determined in the second determination that the temperature in the bath-side combustion chamber has not dropped by a predetermined temperature from the maximum temperature ,
When the count reaches a predetermined number, it is determined that an abnormality has occurred in the temperature detecting means. The controller according to claim 1, wherein the controller resets the count to 0 when the controller determines in the second determination that the temperature in the bath-side combustion chamber is lower than the maximum temperature by a predetermined temperature. Bath water heater as described. The hot water supply side combustion chamber and the bath side combustion chamber are arranged adjacent to each other with a partition member interposed therebetween, and the partition member is provided with the temperature detection means, and the temperature detection means is used to burn the hot water supply side burner. Is also detectable,
3. The bath water heater according to claim 1, wherein the controller makes the first determination when only the bath-side burner is burning. 4. The hot water supply side combustion chamber and the bath side combustion chamber are arranged adjacent to each other with a partition member interposed therebetween, and the partition member is provided with the temperature detection means, and the temperature detection means is used to burn the hot water supply side burner. Is also detectable,
The bath hot water supply apparatus according to claim 1, wherein the controller does not perform the second determination when the hot water supply side burner burns during the second determination time. The predetermined number is 2 or more, and the controller determines that the temperature in the bath-side combustion chamber has increased by a predetermined temperature from the initial temperature in the first determination when the count is less than the predetermined number. The bath water heater according to any one of claims 1 to 4, wherein the count is reset to 0 in such a case.

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