JP6851152B2 - Heating device - Google Patents

Description

The present invention relates to a heating device including a heat exchanger that is heated by the combustion exhaust of a burner.

The heating device includes a burner, a heat exchanger heated by the combustion exhaust of the burner, and a circulation path for circulating hot water heated by the heat exchanger with a circulation pump. A heater installed indoors is provided in the middle of the circulation path. The hot water heated by the heat exchanger circulates in a circulation path provided with a heater, and heat is dissipated from the heater to heat the room.

An exhaust pipe for exhausting the combustion exhaust gas generated by the combustion of the burner to the outside is connected to the heating device. The heat exchange device described in Patent Document 1 is provided with an exhaust temperature sensor (exhaust temperature detecting means) that detects the temperature inside the exhaust passage (exhaust pipe). If the exhaust temperature sensor is short-circuited or disconnected, the exhaust temperature sensor may not be able to detect the temperature normally, and the detected temperature may deviate from the appropriate temperature. In the heat exchange device described in Patent Document 1, when the temperature detected by the exhaust temperature sensor deviates from the appropriate temperature during combustion of the burner, the opening degree of the gas amount adjusting valve inserted in the gas circuit to the burner is adjusted. The amount of combustion of the squeezing and burner is reduced. By performing such control and lowering the temperature of the combustion exhaust gas flowing through the exhaust pipe, a short circuit or disconnection of the exhaust temperature sensor is dealt with.

Japanese Unexamined Patent Publication No. 8-226703

The heat exchange device described in Patent Document 1 deals with a short circuit or disconnection of the exhaust temperature sensor, but when the exhaust temperature sensor fails, the output value of the exhaust temperature sensor is predetermined with respect to the actual temperature. There is also an intermediate failure that is output in a state where the value is off. In this intermediate failure, it may be determined that the temperature detected by the exhaust temperature sensor is an appropriate temperature, and in this case, the abnormality of the exhaust temperature sensor cannot be detected.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a heating device capable of reliably detecting a failure of a temperature sensor that detects an exhaust temperature.

The heating device of the present invention includes a circulation path through which a heat medium flows, a heating terminal provided in the middle of the circulation path, and a heat exchanger provided in the middle of the circulation path on the upstream side of the heating terminal. By burning the burner that heats the heat exchanger, the exhaust pipe that discharges the combustion exhaust gas of the burner to the outside, and the burner, the heat medium heated by the heat exchanger is circulated to the heating terminal. A heating control means for executing the heating operation, an inflow water temperature detecting means for detecting the temperature of the heat medium flowing into the heat exchanger, and an exhaust temperature detecting means for detecting the temperature inside the downstream side of the exhaust pipe. When the detection temperature by the exhaust temperature detecting means becomes equal to or lower than the detection temperature by the inflow water temperature detecting means during the heating operation, the abnormality detecting means for detecting the abnormality of the exhaust temperature detecting means and the abnormality detecting means. A can body including the burner, and the circulation path passes through the can body again on the upstream side of the heating terminal after passing through the heat exchanger and exiting the can body. It is a feature.

According to the present invention, when the burner is burned and the heat medium is heated by the heat exchanger (for example, 80 ° C.), if the exhaust temperature detecting means is operating normally, the exhaust temperature detecting means may be used. The combustion exhaust gas of the burner is sent, and the detection temperature by the exhaust temperature detecting means exceeds the detection temperature (for example, 60 ° C) by the inflow water temperature detecting means flowing into the heat exchanger, for example, about 65 ° C. .. Focusing on this point, when the detection temperature by the exhaust temperature detecting means is equal to or lower than the detected temperature by the inflow water temperature detecting means, the abnormality of the exhaust temperature detecting means is detected, so that the exhaust temperature detecting means can be easily used. Abnormality can be detected. Further, since the temperature difference between the temperature detected by the inflow water temperature detecting means (for example, 60 ° C) and the temperature detected by the exhaust temperature detecting means (for example, 65 ° C) is small, there is an abnormality in the exhaust temperature detecting means. In some cases, the temperature detected by the exhaust temperature detecting means tends to be equal to or lower than the temperature detected by the inflow water temperature detecting means, and an abnormality can be detected at an early stage.

Further, the combustion stopping means for stopping the combustion of the burner is provided when the detection temperature by the exhaust temperature detecting means is equal to or higher than a predetermined temperature or when the abnormality detecting means detects an abnormality of the exhaust temperature detecting means. Is preferable.

According to this configuration, when the detection temperature by the exhaust temperature detecting means is equal to or higher than a predetermined temperature, or when the abnormality detecting means detects an abnormality in the exhaust temperature detecting means, the combustion of the burner is stopped, so that the exhaust temperature is detected. Due to an abnormality in the means, high-temperature combustion exhaust gas does not flow into the exhaust pipe. For example, even if the material of the exhaust pipe is vinyl chloride and the heat-resistant temperature is low, it will be damaged by heating. Can be prevented.

Further, it is preferable to provide a combustion amount control means for reducing the combustion amount of the burner by a predetermined amount when the abnormality detecting means detects an abnormality of the exhaust temperature detecting means.

According to this configuration, when the abnormality detecting means detects an abnormality of the exhaust temperature detecting means, the combustion amount of the burner is reduced by a predetermined amount, and if it is a temporary abnormality detection, the abnormality determination based on the detected temperature is performed again. If so, it is possible to prevent the abnormality from being detected. As a result, only permanent abnormalities can be detected.

The system configuration diagram of the heating device of this embodiment. A flowchart showing a flow of processing for detecting the presence or absence of an abnormality in the exhaust temperature sensor.

As shown in FIG. 1, the heating device 1 includes a burner 2 and a can body 3 incorporating the burner 2. The can body 3 includes a combustion chamber 3a for accommodating the burner 2 and an exhaust passage 3b extending from the combustion chamber 3a to exhaust the combustion exhaust gas.

The combustion chamber 3a is provided with a spark plug 4 for igniting the burner 2 and a frame rod 5 for detecting the ignition of the burner 2. An exhaust pipe 6 made of, for example, vinyl chloride for exhausting the combustion exhaust gas to the outside is connected to the downstream end of the exhaust passage 3b. Further, at the downstream end of the exhaust passage 3b, an exhaust temperature sensor 7 for detecting the temperature inside the exhaust passage 3b is provided.

The can body 3 is provided with a combustion fan 8 for supplying combustion air for the burner 2 in the combustion chamber 3a.

Fuel gas is supplied to the burner 2 via the fuel gas supply pipe 9. The fuel gas supply pipe 9 is provided with a source gas solenoid valve 10 and a gas proportional valve 11 in this order from the upstream side thereof. The fuel gas supply pipe 9 is connected to the burner 2 via the burner gas solenoid valve 12.

A heat exchanger 16 is provided inside the can body 3. The heating device 1 includes a circulation path 19 and a water replenishment solenoid valve (not shown) connected to a water supply (not shown) to replenish water to the circulation path 19. The heat exchanger 16 is connected to a part of the circulation path 19. The heat exchanger 16 absorbs heat from the combustion exhaust gas in the can body 3 to heat the water flowing through the circulation path 19.

The circulation path 19 circulates the hot water that has flowed into the heat exchanger 16. The circulation path 19 is provided with a heater 21 installed in the room and a heating pump 22. The drive of the heating pump 22 is controlled by a controller 30, which will be described later.

By driving the heating pump 22, hot water circulates in the circulation path 19 via the heater 21, and the heat radiated from the heater 21 heats the room.

An inflow water temperature sensor 25 for detecting the temperature of hot water before flowing into the heat exchanger 16 is provided on the upstream side of the heat exchanger 16 of the circulation path 19. Further, on the downstream side of the heat exchanger 16 of the circulation path 19, a runoff water temperature sensor 26 for detecting the temperature of the hot water flowing out from the heat exchanger 16 is provided.

The operation of the heating device 1 is collectively controlled by the controller 30. The controller 30 is an electronic circuit unit composed of a CPU, a memory, and the like (not shown), and controls the operation of the heating device 1 by executing a control program of the heating device 1 held in the memory on the CPU.

A remote controller 33 for remotely controlling the heating device 1 is connected to the controller 30 via a remote controller 34. The remote controller 33 is provided with a display unit 35 and an operation switch group (a temperature setting switch for setting the heating temperature, etc.) (not shown).

The detection signals of the frame rod 5, the exhaust temperature sensor 7, the inflow water temperature sensor 25, and the outflow water temperature sensor 26 are input to the controller 30. Further, the operation of the spark plug 4, the combustion fan 8, the original gas solenoid valve 10, the gas proportional valve 11, and the burner gas solenoid valve 12 is controlled by the control signal output from the controller 30.

The controller 30 starts the heating operation when the remote controller 33 is operated by the user and receives a signal from the remote controller 33 to start the heating operation while the heating device 1 is powered on.

The controller 30 opens the original gas solenoid valve 10 and the burner gas solenoid valve 12 in a state where the combustion fan 8 is rotated, and drives the spark plug 4 to ignite the burner 2. After that, the controller 30 operates the heating pump 22, and the gas is set so that the heating temperature by the heater 21 becomes the temperature set by the remote control 33 based on the signals from the inflow water temperature sensor 25 and the outflow water temperature sensor 26. The operation of the proportional valve 11 and the burner gas solenoid valve 12 is controlled to adjust the combustion amount of the burner 2.

Then, when the remote controller 33 is operated by the user and a signal for stopping heating is received from the remote controller 33, the controller 30 closes the original gas solenoid valve 10 and the burner gas solenoid valve 12 to open the burner 2. The fire is extinguished, the heating pump 22 is stopped, and the heating operation is terminated.

[Exhaust temperature sensor abnormality detection processing during heating operation]
The controller 30 controls the exhaust pipe 6 made of vinyl chloride so that the combustion gas equal to or higher than the heat resistant temperature of the exhaust pipe 6 is not discharged based on the temperature detected by the exhaust temperature sensor 7, and the exhaust temperature sensor 7 Performs anomaly detection processing to detect the presence or absence of anomalies.

As shown in FIG. 2, the remote controller 33 is operated to turn on the heating (STEP 1). In this heating on, the controller 30 turns on the heating pump 22, burns the burner 2, and heats the hot water at the heating set temperature (for example, 80 ° C.) according to the heating set temperature. Control combustion.

The controller 30 determines whether or not the temperature T1 detected by the exhaust temperature sensor 7 is equal to or higher than the heat resistant temperature (for example, 70 ° C) of the exhaust pipe 6 (STEP 2).

When the temperature T1 detected by the exhaust temperature sensor 7 is equal to or higher than the heat resistant temperature (70 ° C) of the exhaust pipe 6 (“YES” in STEP 2), the controller 30 detects that it is in an error state, and the heating pump 22 detects it. Is turned off, and an error stop process for stopping the combustion of the burner 2 is performed (STEP 3). In this error stop processing, since the controller 30 may flow the combustion exhaust gas having a heat resistant temperature or higher through the exhaust pipe 6, it is preferable to display a comment indicating that the combustion of the burner 2 has been stopped on the display unit 35. By this burner combustion stop treatment, it is possible to prevent the combustion exhaust gas having a heat resistant temperature or higher from flowing to the exhaust pipe 6 and being damaged.

On the other hand, when the temperature T1 detected by the exhaust temperature sensor 7 is not equal to or higher than the heat resistant temperature (70 ° C) of the exhaust pipe 6 (“NO” in STEP 2), the controller 30 has a temperature T1 detected by the exhaust temperature sensor 7. , It is determined whether or not the temperature detected by the inflow water temperature sensor 25 exceeds T2 (STEP 4).

When the detection temperature T1 of the exhaust temperature sensor 7 does not exceed the detection temperature T2 of the inflow water temperature sensor 25 (“NO” in STEP 4), the controller 30 detects an abnormality of the exhaust temperature sensor 7 and burner 2 Reduces the amount of combustion by a predetermined amount (for example, 10%) (STEP 5). If the temperature T1 detected by the exhaust temperature sensor 7 exceeds the temperature T2 detected by the inflow water temperature sensor 25 (“YES” in STEP4), STEP2 is performed again.

After reducing the amount of combustion by the burner 2 by 10% (STEP 5), whether the abnormality that became "NO" in STEP 4 is permanent or temporary due to the temperature sensors 7 and 25. In order to determine, in the controller 30, the detection temperature T1 by the exhaust temperature sensor 7 exceeds the detection temperature T2 by the inflow water temperature sensor 25, and the detection temperature T1 by the exhaust temperature sensor 7 is less than 70 ° C. It is determined whether or not there is (STEP 6). In STEP 6, it may be determined only whether or not the temperature T1 detected by the exhaust temperature sensor 7 is less than 70 ° C.

When the abnormality of "NO" in STEP 4 is temporary, the temperature T1 detected by the exhaust temperature sensor 7 exceeds the temperature T2 detected by the inflow water temperature sensor 25, and the exhaust temperature sensor 7 is used. It is determined that the detected temperature T1 is less than 70 ° C (“YES” in STEP 6), and the controller 30 stops heating in response to the heating off operation (“YES” in STEP 7). STEP8). If the heating off operation has not been performed (“NO” in STEP 7), STEP 6 is performed again. That is, the abnormality of "NO" in STEP 4 is temporary, the temperature T1 detected by the exhaust temperature sensor 7 exceeds the temperature T2 detected by the inflow water temperature sensor 25, and the exhaust temperature sensor 7 If the detected temperature T1 in is less than 70 ° C (“YES” in STEP 6) and the heating off operation is not performed (“NO” in STEP 7), heating is continuously performed.

On the other hand, when the abnormality of "NO" in STEP 4 is a permanent one caused by the temperature sensors 7 and 25, the temperature T1 detected by the exhaust temperature sensor 7 is the temperature detected by the inflow water temperature sensor 25. It is determined that the temperature does not exceed T2 (for example, T1 is 40 ° C and T2 is 55 ° C), or the temperature detected by the exhaust temperature sensor 7 is not less than 70 ° C (“NO” in STEP 6). , The controller 30 performs an error stop process (STEP 3). Note that STEP5 to STEP8 may be deleted, and STEP3 (error stop) may be performed when STEP4 is "NO". Moreover, STEP2 may be deleted.

In the present embodiment, when the exhaust temperature sensor 7 operates normally and the temperature T1 detected by the exhaust temperature sensor 7 is not equal to or higher than the heat resistant temperature (70 ° C) of the exhaust pipe 6 (“NO” in STEP 2). The detection temperature T1 of the exhaust temperature sensor 7 is about 65 ° C, and the detection temperature T2 of the inflow water temperature sensor 25 is about 60 ° C. Therefore, it is determined that the temperature T1 detected by the exhaust temperature sensor 7 exceeds the temperature T2 detected by the inflow water temperature sensor 25 (“YES” in STEP4), STEP2 is performed again, and thereafter, STEP2 and STEP4 Is repeated, and heating is continued.

Further, even when the detection temperature T1 of the exhaust temperature sensor 7 does not exceed the detection temperature T2 of the inflow water temperature sensor 25 (“NO” in STEP 4), the exhaust temperature sensor 7 or the inflow water temperature sensor 25 is abnormal. Whether it is a permanent abnormality detection caused by the cause or a temporary abnormality detection caused by another factor cannot be immediately determined. Therefore, when the result is "NO" in STEP 4, the controller 30 reduces the amount of combustion by the burner 2 by 10% (STEP 5).

In the present embodiment, a state in which the detection temperature T1 of the exhaust temperature sensor 7 does not exceed the detection temperature T2 of the inflow water temperature sensor 25 (“NO” in STEP 4) is a temporary abnormality detection, and the exhaust temperature sensor When 7 is operating normally, when the amount of combustion by the burner 2 is reduced by 10% (STEP 5), the detection temperature T1 by the exhaust temperature sensor 7 is about 60 ° C, and the detection temperature T2 by the inflow water temperature sensor 25 is about 60 ° C. It will be about 55 ° C. Therefore, it is determined that the detection temperature T1 by the exhaust temperature sensor 7 exceeds the detection temperature T2 by the inflow water temperature sensor 25, and the detection temperature T1 by the exhaust temperature sensor 7 is less than 70 ° C (in STEP 6). If the heating off operation is not performed (“NO” in STEP 7), the heating is continuously performed.

On the other hand, when the exhaust temperature sensor 7 is not operating normally (intermediate failure), the temperature T1 detected by the exhaust temperature sensor 7 is still high even if the burner 2 controls to reduce the combustion amount by 10% (STEP5). The temperature detected by the inflow water temperature sensor 25 is about 40 ° C (a predetermined intermediate value), and the temperature T2 is about 55 ° C. Therefore, it is determined that the detection temperature T1 of the exhaust temperature sensor 7 does not exceed the detection temperature T2 of the inflow water temperature sensor 25 (“NO” in STEP 6), and the controller 30 performs an error stop process (STEP 3). ).

In this way, when it is determined that the detection temperature T1 by the exhaust temperature sensor 7 does not exceed the detection temperature T2 by the inflow water temperature sensor 25, the exhaust temperature sensor 7 is not operating normally ( Since the intermediate failure) is detected, the abnormality (intermediate failure) of the exhaust temperature sensor 7 can be easily detected.

It should be noted that the detection temperature other than the detection temperature T2 by the inflow water temperature sensor 25, for example, the temperature of the combustion air supplied into the combustion chamber 3a (supply air temperature) is detected, and the detection temperature T1 by the exhaust temperature sensor 7 is set. It is also conceivable to detect an abnormality (intermediate failure) of the exhaust temperature sensor 7 when it is determined that the detected supply air temperature (for example, 25 ° C.) is not exceeded. However, when the exhaust temperature sensor 7 is operating normally, the detected temperature T1 by the exhaust temperature sensor 7 is about 65 ° C, and the difference from the detected supply air temperature (25 ° C) is large (40 ° C). degree). Therefore, even if an abnormality (intermediate failure) occurs in the exhaust temperature sensor 7, it takes time for the detection temperature T1 of the exhaust temperature sensor 7 to fall below the detected supply air temperature (25 ° C), and the exhaust temperature. The abnormality of the sensor 7 cannot be detected at an early stage.

On the other hand, in the present embodiment, when the exhaust temperature sensor 7 is operating normally, the detection temperature T1 by the exhaust temperature sensor 7 is about 65 ° C, and the detection temperature T2 by the inflow water temperature sensor 25 is 60. It is about ° C, and the difference is small (about 5 ° C). As a result, when an abnormality (intermediate failure) occurs in the exhaust temperature sensor 7, the temperature T1 detected by the exhaust temperature sensor 7 becomes equal to or less than the temperature T2 (60 ° C) detected by the inflow water temperature sensor 25. The time is shorter than that detected using the supply air temperature, and the abnormality can be detected at an early stage.

In the above embodiment, the amount of combustion by the burner 2 is reduced by 10% in STEP5, it is confirmed in STEP6 whether it is a temporary abnormality, and it is determined as "NO" in STEP6 (determination that it is a permanent abnormality). In this case, although the error stop processing (STEP3) is performed, the amount of combustion by the burner 2 may be reduced a plurality of times to confirm whether or not the abnormality is temporary. In this case, after the determination in STEP 6 is "NO", it is determined whether or not the determination has reached a predetermined number of times (for example, 3 times), and if the determination has not reached 3 times (1st or 2nd time). Performs STEP 5 again. Then, when the number reaches three times, an error stop process (STEP3) is performed. Further, the rate of reducing the combustion amount is not limited to 10%, and the combustion amount may be reduced. For example, when the combustion amount is set to three stages of large, medium, and small, and the combustion amount is large or medium. May change the amount of combustion to a small amount.

In the above embodiment, the present invention is implemented in a heating device 1 including one burner 2 and a heat exchanger 16, but two burners and two heat exchangers are provided, and each of them is individually provided. The present invention can also be applied to a heating device controlled by the above. The present invention can also be applied to a heating device that distributes hot water to a plurality of heating terminals.

1 ... Heating device, 2 ... Burner, 3 ... Can body, 3a ... Combustion chamber, 3b ... Exhaust path, 6 ... Exhaust pipe, 7 ... Exhaust temperature sensor, 16 ... Heat exchanger, 19 ... Circulation path, 25 ... Inflow water Temperature sensor, 30 ... controller

Claims (3)

The circulation path through which the heat medium circulates,
A heating terminal provided in the middle of the circulation path and
A heat exchanger provided on the upstream side of the heating terminal in the middle of the circulation path, and
A burner that heats the heat exchanger and
An exhaust pipe that discharges the combustion exhaust gas of the burner to the outside,
A heating control means for executing a heating operation in which a heat medium heated by the heat exchanger is distributed to the heating terminal by burning the burner.
Inflow water temperature detecting means for detecting the temperature of the heat medium flowing into the heat exchanger, and
Exhaust temperature detecting means for detecting the temperature inside the downstream side of the exhaust pipe, and
When the temperature detected by the exhaust temperature detecting means becomes equal to or lower than the temperature detected by the inflow water temperature detecting means during the heating operation, the abnormality detecting means for detecting the abnormality of the exhaust temperature detecting means and the abnormality detecting means.
The can body containing the burner and
Equipped with a,
The heating device is characterized in that the circulation path passes through the heat exchanger, exits from the can body, and then passes through the can body again on the upstream side of the heating terminal. In the heating device according to claim 1,
When the detection temperature by the exhaust temperature detecting means is equal to or higher than a predetermined temperature, or when the abnormality detecting means detects an abnormality of the exhaust temperature detecting means, the combustion stopping means for stopping the combustion of the burner is provided. A characteristic heating device. In the heating device according to claim 1,
A heating device including a combustion amount control means for reducing the combustion amount of the burner by a predetermined amount when the abnormality detecting means detects an abnormality of the exhaust temperature detecting means.

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