Combustion device

Abstract

To provide a combustion device capable of inexpensively restraining reduction in accuracy of flame detection of an ultraviolet sensor by a temperature drift of sensitivity.SOLUTION: The hot water supply device 1 includes the combustor 110, the heat exchanger 140 that is heated by the flame generated by the combustor 110 and exchanges heat with passing water, the temperature detector 170 that detects the temperature of the heat exchanger 140, the ultraviolet sensor 160 that is disposed in the vicinity of the combustor 110 and detects the flame generated by the combustor 110, and the controller (corrector) that corrects the detection value of the ultraviolet sensor 160 based on the temperature of the heat exchanger 140 detected by the temperature detector 170. The control unit determines whether or not the combustion unit 110 generates a flame based on a detection value of the ultraviolet sensor 160, and performs an abnormality process in a case where it is determined that a flame is not generated when the combustion unit 110 is operated and in a case where it is determined that a flame is generated when the combustion unit 110 is not operated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a combustion device, and is suitable for use in, for example, a water heater. [Background technology]

[0002] Conventionally, there has been known a water heater that uses an ultraviolet sensor to detect a flame generated by a combustion unit. For example, Patent Document 1 describes a water heater that includes a mixed gas supply passage for supplying a mixed gas of fuel gas and air to the combustion unit, and a flame sensor located in the mixed gas supply passage that detects a backfire flame when the backfire occurs from the combustion unit to the mixed gas supply passage, and in which the ultraviolet sensor is used as the flame sensor. The ultraviolet sensor detects the flame by detecting ultraviolet rays contained in the flame.

[0003] In Patent Document 1, an ultraviolet sensor detects a flashback flame from a combustion unit. Alternatively, a water heater can be configured so that an ultraviolet sensor detects a flame generated by the combustion unit during normal combustion. In this case, the location where the ultraviolet sensor is installed is susceptible to heat from the flame in the combustion unit, and the temperature around the ultraviolet sensor, i.e., the ambient temperature, tends to be relatively high. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-91932 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, when the ambient temperature of the UV sensor becomes high, there is a concern that the sensitivity of the UV sensor may drift with temperature. If temperature drift occurs, the output signal of the UV sensor will shift, and the output signal will not be accurate according to the amount of UV light, which may result in inaccurate flame detection.

[0006] In view of the above problem, an object of the present invention is to provide a combustion device that can inexpensively suppress a decrease in the accuracy of flame detection by an ultraviolet sensor due to temperature drift of sensitivity. [Means for solving the problem]

[0007] A combustion device according to a first aspect of the present invention comprises a combustion unit, a heat exchanger that is heated by a flame generated by the combustion unit and exchanges heat with water passing through it, a temperature detection unit that detects the temperature of the heat exchanger, an ultraviolet sensor that is arranged near the combustion unit and detects the flame generated by the combustion unit, and a correction unit that corrects the detection value of the ultraviolet sensor based on the temperature of the heat exchanger detected by the temperature detection unit.

[0008] The "temperature of the heat exchanger" is a concept that refers not only to the temperature of the heat exchanger itself, but also to the temperature of the pipes connected to the heat exchanger in the vicinity of the heat exchanger.

[0009] The combustion device according to this aspect can correct the detection value of the ultraviolet sensor according to the ambient temperature of the ultraviolet sensor, which is predicted based on the temperature of the heat exchanger. This makes it less susceptible to temperature shifts in the sensitivity of the ultraviolet sensor due to increases in ambient temperature, and reduces the deterioration of the accuracy of flame detection by the ultraviolet sensor. Moreover, because no temperature detector for detecting the ambient temperature is provided, the reduction of the deterioration of flame detection accuracy can be achieved inexpensively.

[0010] A combustion device according to a second aspect of the present invention comprises a combustion unit, a heat exchanger that is heated by a flame generated by the combustion unit and exchanges heat with water passing through it, a temperature detection unit that detects the temperature of the heat exchanger, an ultraviolet sensor that is arranged near the combustion unit and detects the flame generated by the combustion unit, and a correction unit that corrects a threshold value that is compared with the detection value of the ultraviolet sensor based on the temperature of the heat exchanger detected by the temperature detection unit.

[0011] In the combustion device according to this aspect, the threshold value for comparison with the detection value of the UV sensor can be corrected in accordance with the ambient temperature of the UV sensor, which is predicted based on the temperature of the heat exchanger. This makes it less susceptible to temperature shifts in the sensitivity of the UV sensor due to increases in ambient temperature, and reduces the deterioration of the accuracy of flame detection by the UV sensor. Moreover, because no temperature detection unit for detecting the ambient temperature is provided, the reduction of the deterioration of flame detection accuracy can be achieved inexpensively. [Effects of the Invention]

[0012] As described above, according to the present invention, it is possible to provide a combustion apparatus that can inexpensively suppress a decrease in the accuracy of flame detection by an ultraviolet sensor due to temperature drift of sensitivity.

[0013] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the embodiments shown below are merely examples of how the present invention can be implemented, and the present invention is not limited to the embodiments described below. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing a configuration of a water heater according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing a circuit block of the water heater according to the first embodiment. [Figure 3] Fig. 3(a) is a diagram showing the relationship between the temperature detected by the temperature detection unit, the predicted ambient temperature of the UV sensor, and the sensitivity correction value of the UV sensor according to embodiment 1. Fig. 3(b) is a diagram showing the configuration of a sensitivity correction value determination table according to embodiment 1. [Figure 4] FIG. 4 is a diagram showing an abnormality detection process of the combustion unit executed by the control unit according to the first embodiment. [Figure 5] FIG. 5 is a diagram showing an abnormality detection process of the combustion unit executed by the control unit according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a combustion apparatus according to the present invention will now be described with reference to the accompanying drawings. In this embodiment, the present invention is applied to a water heater.

[0016] <Embodiment 1> FIG. 1 is a diagram showing a configuration of a water heater 1 according to the first embodiment.

[0017] 1, water heating apparatus 1 includes water heater 10 and remote controller 20. Water heater 10 is installed outdoors or indoors. Remote controller 20 is installed, for example, in an indoor kitchen, has an operation display unit such as a touch panel, and is used to set the hot water temperature and display various information.

[0018] Water heater 10 includes housing 100 that forms the outer shell of the water heater. An intake port 101 and an exhaust port 102 are provided on the top surface of housing 100. Within housing 100, a combustion case 103 and a can body 104 are arranged side by side in the vertical direction.

[0019] A combustion section 110 is disposed in the lower portion of the combustion case 103. The combustion section 110 has a burner 111 and an igniter 112. A mixed gas supply path 105 is formed in a serpentine manner above the combustion section 110 in the combustion case 103. An intake fan 120 and a fuel supply pipe 130 are connected to the inlet of the mixed gas supply path 105. An electromagnetic valve 131, the opening and closing amount of which is adjustable, is provided in the fuel supply pipe 130. A fuel gas flows through the fuel supply pipe 130. In this embodiment, the fuel gas is hydrogen gas.

[0020] A heat exchanger 140 is disposed within the can body 104. The heat exchanger 140 is composed of piping 141 through which water flows and a number of fins 142. The piping 141, i.e., the inlet section 140a and outlet section 140b of the heat exchanger 140, extend out from the can body 104. A water inlet pipe 151 is connected to the inlet section 140a, and a hot water outlet pipe 152 is connected to the outlet section 140b. Outside the housing 100, the water inlet pipe 151 is connected to a water faucet, and the hot water outlet pipe 152 is connected to a faucet or the like. The heat exchanger 140, the water inlet pipe 151, and the hot water outlet pipe 152 are made of metal.

[0021] A detection case 106 is disposed on the outside of the upper end of the can body 104. A window 106a facing the inside of the can body 104 is provided in the detection case 106. An ultraviolet sensor 160 for detecting the flame generated by the combustion unit 110 is disposed inside the detection case 106. The ultraviolet sensor 160 is disposed inside the detection case 106, and is thereby disposed near the combustion unit 110. The ultraviolet sensor 160 outputs a detection value corresponding to the amount of ultraviolet light contained in the flame, for example, an analog detection signal (detection voltage) having a magnitude corresponding to the amount of light.

[0022] A temperature detection unit 170 is disposed at outlet 140b of heat exchanger 140. Temperature detection unit 170 is, for example, a thermistor, and detects the temperature of heat exchanger 140, specifically, the temperature of outlet 140b located outside can body 104.

[0023] An exhaust duct 107 is connected to the lower end of the can body 104. The exhaust duct 107 extends upward from the lower end of the can body 104 and is connected to the exhaust port 102.

[0024] When water heater 10 supplies hot water, air supply fan 120 operates, and external air taken in through air intake 101 is introduced into mixed gas supply path 105. Also, electromagnetic valve 131 is opened, and fuel gas is introduced from fuel supply pipe 130 into mixed gas supply path 105. The air and fuel gas are mixed in mixed gas supply path 105 to form mixed gas, and this mixed gas is supplied to combustion section 110. Igniter 112 ignites burner 111, and combustion section 110 burns the mixed gas to generate a flame. The flame is generated at the upper end of can body 104. Ultraviolet rays contained in the flame enter detection case 106 through window 106a and are detected by ultraviolet sensor 160.

[0025] Air heated by the flame in the combustion section 110 flows downward within the can body 104 as combustion gas and passes through the heat exchanger 140. The combustion gas heats the heat exchanger 140. The heat exchanger 140 is heated by the combustion gas generated by the flame in the combustion section 110. Therefore, it can be said that the heat exchanger 140 is heated by the flame.

[0026] Water from the faucet flows through the water inlet pipe 151 and is introduced into the heat exchanger 140. The water passing through the heat exchanger 140 is heated by heat exchange with the combustion gas and becomes hot water. The hot water leaves the heat exchanger 140 and flows through the hot water outlet pipe 152 to be supplied to a faucet or the like.

[0027] The temperature of outlet 140b of heat exchanger 140 is detected by temperature detection unit 170. The temperature detected by temperature detection unit 170 correlates with the temperature of the hot water coming out of heat exchanger 140, i.e., the temperature of the hot water coming out of water heater 10 (outlet hot water temperature). Therefore, the outlet hot water temperature can be predicted from the temperature detected by temperature detection unit 170. When the detected temperature is close to the outlet hot water temperature, the detected temperature can also be considered as the outlet hot water temperature.

[0028] The combustion gas that has passed through the heat exchanger 140 passes through the exhaust duct 107 and is discharged to the outside of the housing 100 through the exhaust port 102 .

[0029] FIG. 2 is a diagram showing a circuit block of the water heater 10 according to the first embodiment.

[0030] The water heater 10 includes a control unit 201, a storage unit 202, and a communication unit 203.

[0031] Control unit 201 includes a microcomputer. A signal corresponding to a detected value is output from ultraviolet sensor 160 to control unit 201, and a signal corresponding to a detected temperature is output from temperature detection unit 170. Since the signal from ultraviolet sensor 160 is very small, it is amplified by an amplifier circuit or the like and then sent to control unit 201. Control unit 201 controls each part in water heater 10, such as igniter 112, air supply fan 120, and electromagnetic valve 131, according to a program stored in memory unit 202.

[0032] The storage unit 202 includes a memory and stores a predetermined control program. The communication unit 203 communicates with the remote controller 20 under the control of the control unit 201.

[0033] When supplying hot water, after ignition of combustion unit 110, control unit 201 adjusts the amount of fuel gas supplied by electromagnetic valve 131 and adjusts the amount of combustion by combustion unit 110 based on the temperature detected by temperature detection unit 170 so that the temperature of hot water discharged from water heater 10 becomes the set temperature preset by remote controller 20. In this way, control unit 201 controls the operation of combustion unit 110 based on the temperature detected by temperature detection unit 170.

[0034] Furthermore, if the temperature detected by the temperature detection unit 170 reaches an abnormally high temperature, the control unit 201 closes the electromagnetic valve 131 to stop the operation of the combustion unit 110. This prevents damage to the heat exchanger 140 and the hot water outlet pipe 152 due to empty heating.

[0035] Furthermore, the control unit 201 executes the following abnormality detection process for the combustion unit 110. That is, the control unit 201 acquires detection values ​​from the ultraviolet sensor 160 both when hot water is being supplied and when hot water supply is stopped, i.e., both when the combustion unit 110 is operating and when it is stopped, and determines whether or not the combustion unit 110 is generating a flame based on the detection values. Then, when the control unit 201 determines that no flame is being generated when the combustion unit 110 is operating, or when it determines that a flame is being generated when the combustion unit 110 is not operating, the control unit 201 executes abnormality processing such as an abnormality notification.

[0036] Incidentally, ultraviolet sensor 160 needs to be positioned relatively close to the flame so that it can easily receive ultraviolet rays from the flame in combustion section 110. For this reason, the inside of detection case 106 where ultraviolet sensor 160 is located is easily subjected to heat from the flame, and the temperature inside detection case 106, i.e., the ambient temperature of ultraviolet sensor 160, is likely to become relatively high. When the ambient temperature becomes high, temperature drift is likely to occur in the sensitivity of ultraviolet sensor 160, and this temperature drift causes a shift in the detection value of ultraviolet sensor 160, making it impossible to obtain an accurate detection value corresponding to the amount of ultraviolet light, and there is a risk that accurate flame detection will not be possible.

[0037] Therefore, in the above-mentioned abnormality detection process, it is conceivable to detect the ambient temperature of the ultraviolet sensor 160 (air temperature inside the detection case 106), correct the sensitivity of the ultraviolet sensor 160 according to the ambient temperature, and correct the detection value based on the sensitivity correction value.

[0038] However, if a temperature detection unit such as a thermistor is disposed in the detection case 106 to detect the ambient temperature of the ultraviolet sensor 160, an increase in costs due to an increase in the number of parts and assembly steps is unavoidable.

[0039] When the combustion unit 110 generates a flame, the heat not only increases the ambient temperature of the ultraviolet sensor 160 but also increases the temperature of the heat exchanger 140. Therefore, the ambient temperature correlates with the temperature of the heat exchanger 140, and it is therefore possible to predict the ambient temperature based on the temperature detected by the temperature detection unit 170 disposed at the outlet 140b of the heat exchanger 140.

[0040] Therefore, in this embodiment, in the abnormality detection process, the ambient temperature of the ultraviolet sensor 160 is predicted based on the temperature detected by the temperature detection unit 170, the sensitivity of the ultraviolet sensor 160 is corrected according to the predicted ambient temperature, and the detection value is corrected based on the sensitivity correction value. This makes it possible to inexpensively suppress a decrease in the accuracy of flame detection by the ultraviolet sensor 160 due to temperature drift of sensitivity.

[0041] Fig. 3(a) is a diagram showing the relationship between the detected temperature of the temperature detection unit 170, the predicted ambient temperature of the ultraviolet sensor 160, and the sensitivity correction value of the ultraviolet sensor 160 according to the first embodiment. Fig. 3(b) is a diagram showing the configuration of a sensitivity correction value determination table 202a according to the first embodiment.

[0042] 3(a), within a range from the ambient temperature at which sensitivity correction of the ultraviolet sensor 160 is required to the ambient temperature that may be increased by the flame of the combustion section 110, each ambient temperature predicted from each detected temperature of the temperature detection section 170 is obtained by conducting experiments in advance. Also, each sensitivity correction value corresponding to each ambient temperature is determined by conducting experiments in advance. Each sensitivity correction value corresponding to each ambient temperature differs depending on the temperature characteristics of the ultraviolet sensor 160.

[0043] The higher the detected temperature of the temperature detection unit 170, the higher the predicted ambient temperature of the ultraviolet sensor 160. Furthermore, the higher the ambient temperature, the larger the sensitivity correction value of the ultraviolet sensor 160. The detected temperature is the temperature of the metal pipe 141, and the ambient temperature is the temperature of the air. For this reason, the detected temperature is generally higher than the ambient temperature, but the opposite may also be true depending on the arrangement of the ultraviolet sensor 160 and the temperature detection unit 170.

[0044] Using each detected temperature and each sensitivity correction value corresponding to each ambient temperature predicted from each detected temperature shown in FIG. 3(a), a sensitivity correction value determination table 202a for determining a sensitivity correction value according to each detected temperature shown in FIG. 3(b) is created and stored in the memory unit 202.

[0045] The values ​​of the detected temperature, the ambient temperature, and the sensitivity correction value shown in FIGS. 3(a) and 3(b) are merely tentative values.

[0046] 4 is a diagram showing an abnormality detection process for the combustion unit 110 executed by the control unit 201 according to the first embodiment. In the abnormality detection process, the control unit 201 functions as a correction unit and corrects the detection value of the ultraviolet sensor 160 based on the temperature of the heat exchanger 140 detected by the temperature detection unit 170.

[0047] 4, control unit 201 acquires a detection value from ultraviolet sensor 160 (S101). Furthermore, control unit 201 acquires a detected temperature from temperature detection unit 170 (S102).

[0048] Next, the control unit 201 corrects the detection value of the ultraviolet sensor 160 based on the detected temperature of the temperature detection unit 170 (S103). That is, the control unit 201 refers to the sensitivity correction value determination table 202a and reads out from the sensitivity correction value determination table 202a the sensitivity correction value associated with the detected temperature closest to the acquired detected temperature. Then, based on the read sensitivity correction value, the control unit 201 corrects the detection value of the ultraviolet sensor 160 so as to increase it by an amount corresponding to the sensitivity correction value.

[0049] When the combustion unit 110 is not generating a flame or has just generated a flame, the acquired detected temperature may be lower than the minimum detected temperature in the sensitivity correction value determination table 202a. In this case, the control unit 201 does not correct the detection value of the ultraviolet sensor 160.

[0050] Next, the control unit 201 determines whether or not the detection value of the ultraviolet sensor 160 is greater than the threshold value (S104). If the detection value is greater than the threshold value (S104: YES), the control unit 201 determines that the combustion unit 110 is generating a flame, and determines whether or not the combustion unit 110 is being operated (S105).

[0051] If the control unit 201 is operating the combustion unit 110 (S105: YES), the operation is normal, and the process returns to S101. On the other hand, if the control unit 201 is not operating the combustion unit 110 (S105: NO), a flame is occurring in the combustion unit 110 that is not operating, which is abnormal, and the control unit 201 executes abnormality processing and causes the remote controller 20 to issue an abnormality notification indicating that an abnormality has occurred in the combustion unit 110 (S106). For example, a screen notifying the occurrence of an abnormality may be displayed on the remote controller 20, or a sound such as a voice may be output from the remote controller 20 notifying the occurrence of an abnormality.

[0052] On the other hand, if the detection value of the ultraviolet sensor 160 is below the threshold value (S104: NO), the control unit 201 determines that the combustion unit 110 is not generating a flame and determines whether the combustion unit 110 is being stopped (S107).

[0053] If the control unit 201 is in the process of stopping the combustion unit 110 (S107: YES), the operation is normal, and the process returns to S101. On the other hand, if the control unit 201 is not in the process of stopping the combustion unit 110 (S105: NO), the operation of the combustion unit 110 is abnormal because no flame is being generated in the operating combustion unit 110, and the control unit 201 executes abnormality processing, closes the electromagnetic valve 131 to stop the supply of fuel gas from the fuel supply pipe 130, and causes the remote controller 20 to issue an abnormality notification indicating that an abnormality has occurred in the combustion unit 110 (S108).

[0054] <Effects of the First Embodiment> According to water heating apparatus 1, control unit 201 functions as a correction unit to correct the detection value of ultraviolet sensor 160 based on the temperature of heat exchanger 140 detected by temperature detection unit 170.

[0055] According to this configuration, the detection value of the ultraviolet sensor 160 can be corrected according to the ambient temperature of the ultraviolet sensor 160, which is predicted based on the temperature of the heat exchanger 140, so that the sensitivity of the ultraviolet sensor 160 is less susceptible to temperature shifts caused by rising ambient temperatures, and it is possible to suppress a decrease in the accuracy of flame detection by the ultraviolet sensor 160. Moreover, by using the temperature detection unit 170 that detects the temperature of the heat exchanger 140 to control the operation of the combustion unit 110, no temperature detection unit for detecting the ambient temperature is required, so that a decrease in the accuracy of flame detection can be suppressed at low cost.

[0056] Furthermore, according to water heating apparatus 1, control unit 201 determines whether combustion unit 110 is generating a flame based on the detection value of ultraviolet sensor 160, and if it determines that a flame is not being generated when combustion unit 110 is operating, or if it determines that a flame is being generated when combustion unit 110 is not operating, it executes abnormality processing.

[0057] With this configuration, the ultraviolet sensor 160 can detect flames with high accuracy, making it possible to accurately determine whether the combustion section 110 is generating a flame, thereby reducing the risk of erroneous abnormality processing being performed.

[0058] <Embodiment 2> The configuration of water heater 1 of the second embodiment is similar to that of the first embodiment.

[0059] FIG. 5 is a diagram showing an abnormality detection process for the combustion unit 110 executed by the control unit 201 according to the second embodiment.

[0060] In the first embodiment, as shown in FIG. 4, in S103 of the abnormality detection process for the combustion unit 110, the control unit 201 corrects the detection value of the ultraviolet sensor 160 based on the detected temperature of the temperature detection unit 170 (S103).

[0061] 5, in this embodiment, the process of S111 is executed instead of the process of S103 in the abnormality detection process of the combustion unit 110. The other processes are the same as those in the first embodiment.

[0062] That is, in S111, the control unit 201 corrects the threshold value to be compared with the detection value of the ultraviolet sensor 160 based on the detected temperature of the temperature detection unit 170 (S111). Specifically, the control unit 201 refers to the sensitivity correction value determination table 202a and reads out from the sensitivity correction value determination table 202a the sensitivity correction value associated with the detected temperature closest to the acquired detected temperature. Then, based on the read sensitivity correction value, the control unit 201 corrects the threshold value so as to reduce it by an amount corresponding to the read sensitivity correction value. In S104, the acquired detection value of the ultraviolet sensor 160 is compared with the corrected threshold value.

[0063] According to this embodiment, the threshold value to be compared with the detection value of ultraviolet sensor 160 can be corrected in accordance with the ambient temperature of ultraviolet sensor 160 predicted based on the temperature of heat exchanger 140, making it less susceptible to the temperature shift in the sensitivity of ultraviolet sensor 160 caused by rising ambient temperature, and suppressing a decrease in the accuracy of flame detection by ultraviolet sensor 160. Moreover, because no temperature detection unit for detecting ambient temperature is provided, it is possible to inexpensively suppress a decrease in the accuracy of flame detection.

[0064] <Example of change> Although the embodiment of the present invention has been described above, the combustion device according to the present invention is not limited to the configuration of the above embodiment, and various modifications are possible.

[0065] For example, in the first embodiment, the temperature detection unit 170 detects the temperature of the heat exchanger 140 itself. However, the temperature detection unit 170 may detect the temperature of a portion of the hot water outlet pipe 152 connected to the heat exchanger 140 near the heat exchanger 140, thereby substantially detecting the temperature of the heat exchanger 140.

[0066] Furthermore, in the first embodiment, the correction unit that corrects the detection value of the ultraviolet sensor 160 is realized by the function of the control unit 201. However, the correction unit may be realized by a correction circuit.

[0067] Furthermore, in the above-described first embodiment, the detection case 106 that houses the ultraviolet sensor 160 is disposed outside the can body 104. However, the detection case 106 may be disposed inside the can body 104. However, by disposing the detection case 106 outside the can body 104, it is possible to prevent the ambient temperature of the ultraviolet sensor 160 from rising more than when the detection case 106 is disposed inside the can body 104.

[0068] Furthermore, water heater 1 may use a fuel gas other than hydrogen gas.

[0069] Furthermore, the present invention can also be used in combustion devices other than the water heater 1, for example, in hot water heating devices that heat rooms or floors using hot water produced by heat exchange in a heat exchanger heated by the flame of the combustion section.

[0070] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the claims. [Explanation of symbols]

[0071] 1. Hot water supply equipment 110 Combustion section 140 Heat exchanger 160 UV sensor 170 Temperature detection unit 201 Control unit (correction unit)

Claims

1. A combustion section; a heat exchanger in which heat is exchanged between the combustion chamber and water passing through the heat exchanger and the flame generated by the combustion chamber; a temperature detection unit that detects the temperature of the heat exchanger; an ultraviolet sensor disposed near the combustion unit for detecting a flame generated by the combustion unit; a correction unit that corrects the detection value of the ultraviolet sensor based on the temperature of the heat exchanger detected by the temperature detection unit; A combustion device comprising:

2. A combustion section; a heat exchanger in which heat is exchanged between the combustion chamber and water passing through the heat exchanger and the flame generated by the combustion chamber; a temperature detection unit that detects the temperature of the heat exchanger; an ultraviolet sensor disposed near the combustion unit for detecting a flame generated by the combustion unit; a correction unit that corrects a threshold value to be compared with the detection value of the ultraviolet sensor based on the temperature of the heat exchanger detected by the temperature detection unit; A combustion device comprising:

3. The combustion apparatus according to claim 1 or 2, Further provided is a control unit that controls the operation of the combustion unit, The control unit determining whether the combustion unit is generating a flame based on the detection value of the ultraviolet sensor; When it is determined that a flame is not generated when the combustion unit is operating, and when it is determined that a flame is generated when the combustion unit is not operating, an abnormality process is executed. A combustion device characterized by:

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