JP2935958B2 - Indoor installation type combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device such as a gas water heater, and more particularly to an indoor installation type combustion device having a device for detecting incomplete combustion.

[0002]

2. Description of the Related Art Conventionally, as this type of apparatus, for example,
A burner is housed in a combustion chamber of a gas water heater installed indoors, and exhaust means such as an exhaust tube for exhausting exhaust gas in the combustion chamber to the outside is provided. A combustion fan for discharging the exhaust gas to the exhaust means,
2. Description of the Related Art There is known an apparatus provided with combustion control means for controlling the combustion of the burner and fan control means for controlling the drive of the combustion fan. The fan control means drives the combustion fan during combustion of the burner, and after the burner is stopped, drives the combustion fan for a predetermined time for post-purging, and then stops the combustion fan. If the post-purge is performed for about 5 to 10 seconds after the stop of the combustion, the exhaust gas in the combustion chamber can be sufficiently discharged.

[0003] The gas water heater further detects the CO concentration in the exhaust gas, compares the CO concentration with a reference value, and, when a CO concentration exceeding the reference value is detected, detects if the burner is incomplete. Incomplete combustion detecting means for detecting combustion, and combustion stopping means for stopping combustion of the burner when incomplete combustion of the burner is detected are provided, and incomplete combustion of the burner is detected. Sometimes the combustion of the burner is immediately stopped.

In recent years, as the robustness of buildings has been improved, highly airtight rooms have been created. Such a highly airtight room is excellent in heat insulation and easily obtains a cooling / heating effect, but outside air cannot be taken in unless forced ventilation is performed.

When the gas water heater is installed in such a highly airtight room, the air in the highly airtight room is supplied to the gas water heater as combustion air. And the incomplete combustion tends to occur. The tendency is further increased when a combustion device of a type that exhausts exhaust gas such as a gas cooker or a gas fan heater into a room is installed in the same room as the gas water heater.

In such a case, when the incomplete combustion is detected in the gas water heater, the combustion of the burner is stopped immediately, and when the CO gas in the combustion chamber is discharged by the post-purge, the burner can be used again. You can do it. However, as described above, when the cause of incomplete combustion is a decrease in the oxygen concentration in the air around the gas water heater, that is, when necessary and sufficient ventilation is not performed in a highly airtight room, the gas water heater is immediately ignited. Then, incomplete combustion occurs again, and there is a disadvantage that the gas water heater cannot be used substantially.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved combustion device.

That is, an object of the present invention is to eliminate such inconveniences and forcibly ventilate the air in the room when incomplete combustion is detected due to a decrease in the oxygen concentration in the air in the room. An object of the present invention is to provide a combustion device that enables combustion.

[0009]

In order to achieve the above object, a first aspect of the indoor installation type combustion apparatus of the present invention is as follows.
A combustion chamber containing a burner, exhaust means for exhausting exhaust gas in the combustion chamber to the outside, and a combustion fan for blowing indoor air to the burner as combustion air and discharging the exhaust gas to the exhaust means. Combustion control means for controlling the combustion of the burner, incomplete combustion detection means for detecting the CO concentration in the exhaust gas by a CO sensor to detect incomplete combustion of the burner, and incomplete combustion of the burner. An indoor unit comprising: combustion stop means for stopping combustion of the burner when detected; and fan control means for controlling driving of the combustion fan and performing post-purging for a predetermined time when combustion of the burner is stopped. In the stationary combustion device, when the combustion of the burner is stopped by the detection of the incomplete combustion,
Post-purge time setting means for setting the time for performing post-purging to be sufficiently longer than the time required for discharging the exhaust gas in the combustion chamber and performing post-purging sufficient for forcibly ventilating the indoor space is provided. Features.

A second aspect of the indoor-installed combustion apparatus of the present invention is a combustion chamber containing a burner, exhaust means for exhausting exhaust gas in the combustion chamber to the outside, and indoor air in the burner. A combustion fan for blowing air as combustion air and discharging the exhaust gas to the exhaust means, a combustion control means for controlling combustion of the burner, and a CO sensor for detecting a CO concentration in the exhaust gas by a CO sensor. An incomplete combustion detecting means for detecting incomplete combustion of the burner, a combustion stopping means for stopping combustion of the burner when incomplete combustion of the burner is detected, and controlling the combustion fan to control the combustion. Means for performing a first post-purge when the combustion of the burner is stopped by the means, and fan control means for performing a second post-purge when the combustion of the burner is stopped by the combustion stopping means. In the combustion apparatus, the rotational speed of the combustion fan during the second post-purge, the first
And fan rotation speed control means for performing post-purging sufficient to forcibly ventilate the interior by increasing the rotation speed at the time of post-purging.

Further, the present invention is applied to a combustion device such as a gas water heater.

[0012]

According to the first aspect of the combustion apparatus of the present invention, when the combustion of the burner is stopped due to the detection of the incomplete combustion, the time required for discharging the exhaust gas from the combustion chamber is reduced. Since the post-purging is performed for a sufficiently longer time than that, air having a low oxygen concentration in the room is discharged to the outside from the exhaust means, so that a large amount of fresh air is taken in from the outside of the room, and the combustion is restarted. It is in a state where it can be continued.

According to a second aspect of the combustion apparatus of the present invention, when the incomplete combustion is detected and the combustion stopping means stops the combustion of the burner, the combustion control means controls the combustion of the burner. Than when it was stopped
Since the post-purge is performed by increasing the rotation speed of the combustion fan, air having a low oxygen concentration in the room is discharged to the outside from the exhaust means, so that a lot of fresh air is taken in from the outside of the room. Then, the combustion can be continued again.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a combustion apparatus according to the present invention. FIG. 1 is an explanatory sectional view of a room in which a gas water heater as a combustion device of the present embodiment is installed, FIG. 2 is an explanatory sectional view of the gas water heater shown in FIG. 1, and FIG. It is a block diagram which shows the structure of the main control apparatus of the gas water heater shown, and FIG. 4 thru | or FIG. 7 is a flowchart which shows operation | movement of the gas water heater of a present Example.

As shown in FIG. 1, the forced combustion gas water heater A is installed in a highly airtight room R, and has a duct D as an exhaust means for discharging exhaust gas to the outside. The gas water heater A is installed near a sink B provided in the room R, and a gas cooker C is installed on the sink B as another combustion device. The gas cooker C
Has no exhaust means and exhaust gas is directly discharged into the room R. Therefore, if the gas water heater A and the gas cooker C are used at the same time, the air in the room R will have an oxygen concentration. May be in a low state.

As shown in FIG. 2, the gas water heater A is provided with a gas burner 2 for performing combustion in a combustion chamber 1, an intake port 3 for combustion air X below, and a combustion exhaust gas Z above. Exhaust ports 4 are provided for exhausting the air. The air supply port 3 is for taking in the air in the room R.
Is connected to the duct D shown in FIG. A combustion fan 5 having sirocco-type blades provided in the air supply port 3
Thus, the combustion air X of the gas burner 2 is supplied to the combustion chamber 1. Above the gas burner 2 in the combustion chamber 1, a heat exchanger 6 is provided. The gas burner 2 includes a burner group 7 that forms a flame, and an ejection port 8 located below the burner group 7.
, And the fuel gas Y is supplied through the gas pipe 10.

The water heater A is provided with a main controller 11 for controlling the supply and stop of the fuel gas Y to the gas burner 2, the ignition of the gas burner 2, the stop of the combustion of the gas burner 2, and the driving of the combustion fan 5. And a water sensor 1 on the input side
3, a thermistor 14, a frame rod 19, and a CO sensor 20 are connected. On the output side, a source gas solenoid valve 15, a main solenoid valve 16, a governor type gas proportional solenoid valve (hereinafter abbreviated as a proportional valve) 17, and an igniter 18. Is connected.

As shown in FIG. 3, the main controller 11 includes a temperature setting device 12, a water amount sensor 13, a thermistor 14, a source gas solenoid valve 15, a main solenoid valve 16, a proportional valve 17, an igniter 1, and the like.
8. Combustion control means 21 for controlling combustion of gas burner 2 by flame rod 19; CO detection means 22 for detecting incomplete combustion of gas burner 2 based on CO concentration in exhaust gas Z detected by CO sensor 20; 19
A detection means 23 for detecting the extinguishing of the gas burner 2 by detecting the flame of the gas burner 2, a fan control means 24 for controlling the driving of the combustion fan 5, and an abnormality detecting means 25 for detecting an abnormality or the like of the combustion fan 5. It has. Note that the fan control unit 24 also functions as a fan rotation speed control unit 24 that controls the rotation speed of the combustion fan 5.
The abnormality detecting means 25 includes a combustion control means 2 before the start of combustion.
1 and the like, the combustion control means 21 after the start of combustion, C
Failures of the devices such as the O detecting means 22 and the extinguishing detecting means 23 and the ignition failure of the gas burner 2 are also detected as abnormalities of the device.

Further, main controller 11 is provided with CO detecting means 2.
2. Combustion stopping means which is connected to the extinguishing detecting means 23 and the abnormality detecting means 25, and stops the supply of fuel gas to stop the combustion of the gas burner 2 when a malfunction is detected by each of the means 22, 23, 25. 26, the respective means 22,
There is provided a post-purge time setting means 27 for setting a post-purge time of the combustion fan 5 after the detection of the failure in accordance with the failure detected by 23 and 25.

The post-purge time setting means 27 is connected to a four-minute timer 28 and a five-second timer 29 which are selected according to the type of the problem, and each of the timers 28 and 29 is connected to the fan control means 24. Further, the combustion control means 21 is connected to a post-purge time setting means 27 for performing post-purging at the time of normal combustion stop.

Next, the operation of the water heater A having the above configuration will be described with reference to FIGS.

First, as shown in FIG. 4, the operation switch is turned on.
When the hot water tap (not shown) is opened in the state described above, the operation of the water heater A is started. When the hot water tap is opened,
The water amount sensor 13 is turned on, and then the fan control means 24 is operated by the combustion control means 21 so that the combustion fan 5 starts rotating. Then, the abnormality detecting means 25 detects the presence or absence of an abnormality in the combustion fan 5 and the presence or absence of an abnormality in an initial state of each unit of the apparatus.

The presence or absence of an abnormality in the combustion fan 5 is detected based on whether or not the combustion fan 5 reaches a predetermined rotation speed.
The abnormality of the combustion fan 5 detected here may be the air supply port 3 or the exhaust port 4 closed in addition to the abnormality of the combustion fan 5 itself. Abnormalities in the initial state of each part of the device include circuit abnormalities of solenoid valves such as the original gas solenoid valve 15, the main solenoid valve 16, and the proportional valve 17, and the O of the frame rod 10.
N failure, abnormal temperature fuse not shown, thermistor 1
There are 4 abnormalities.

When it is confirmed that there is no abnormality in the initial state of the combustion fan 5 and the various parts of the apparatus, the igniter 18 is turned on by the combustion control means 21, and subsequently the original gas solenoid valve 15,
The main solenoid valve 16 is turned on, and the proportional valve 17 is opened to a predetermined opening to start supplying the fuel gas, and the gas burner 2 is ignited. When the gas burner 2 is ignited and the flame is detected by the frame rod 19, the igniter 18 is turned off, the CO sensor 20 is subsequently turned on, and the combustion of the gas burner 2 is started.

The combustion of the gas burner 2 is detected by the abnormality detecting means 2.
5. If the CO detecting means 22 and the extinction detecting means 23 do not detect incomplete combustion such as abnormality of the apparatus, generation of CO or extinction, the operation is continued until the hot water tap is closed. Here, in addition to the abnormality of the combustion fan 5 itself, if the continuous combustion limiter (not shown) detects that the combustion has continued for 60 minutes or more, the thermistor 14 and the CO sensor 20 There may be an abnormality in itself, a case where the temperature detected by the thermistor 14 becomes 95 ° C. or more, and a boiling prevention device (not shown) is activated. During the combustion of the gas burner 2, proportional control of the fuel gas supplied by the proportional valve 17 is performed.

When the hot water tap is closed, the water quantity sensor 13 is turned off, so that the original gas solenoid valve 15,
The main solenoid valve 16 and the proportional valve 17 are turned off, and a signal is sent to the post-purge time setting means 27. In this case, since the normal combustion is stopped, the 5-second timer 29 is operated. After the exhaust gas in the combustion chamber 1 is discharged to the duct D shown in FIG. 1 by the post-purge, when the 5-second timer 29 times out, the rotation of the combustion fan 5 is stopped by the fan control means 24, and then the CO sensor 20 is stopped and the operation switch is turned off, so that the water heater A
The operation of is ended.

Next, the operation when a failure is detected during the combustion of the gas burner 2 in FIG. 4 will be described with reference to FIGS.

First, as shown in FIG. 4, during the combustion of the gas burner 2, when an abnormality in the apparatus such as the combustion fan 5 or incomplete combustion such as generation or extinguishing of CO is detected, the abnormality detecting means 25, CO A signal is sent from the detecting means 22 or the extinction detecting means 23 to the combustion stopping means 26.

Next, as shown in FIG. 5, the combustion stopping means 26 sets the proportional valve 17, the main solenoid valve 16, and the original gas solenoid valve 15 to O.
By stopping the supply of the fuel gas by performing FF, the combustion of the gas burner 2 is stopped and a signal is sent to the post-purge time setting means 27. In the case of the disappearance, the supply of the fuel gas is stopped by the combustion stopping means 26, and the release of the raw gas is stopped.

Next, the post-purge time setting means 27 activates the 4-minute timer 28 in response to a signal received from the combustion stopping means 26 to operate the 4-minute timer 28 in the case of stopping combustion due to incomplete combustion such as generation of CO or extinguishing. When the combustion is stopped due to an abnormality of the device such as the fan 5, the timer 29 for 5 seconds is operated. Then, after the post-purge, when the 4-minute timer 28 or the 5-second timer 29 times up, the fan control means 24 stops the rotation of the combustion fan 5. Next, when the operation switch is turned off, the water heater A
The operation of is ended.

In this embodiment, as shown in FIG. 1, since the gas water heater A and the gas cooker C are provided in the same room R, the air in the room R has a low oxygen concentration. Become
For this reason, the incomplete combustion may occur. The air in the room R is discharged to the duct D shown in FIG. 1 by setting the post-purge time in such a case to 4 minutes longer than that in the normal combustion stop or the combustion stop due to an abnormality in the apparatus. Since fresh air flows in from outside the room R, the inside of the room R is forcibly ventilated. As a result,
The oxygen concentration in the air in the room R is restored, and it is possible to prevent incomplete combustion from occurring again at the next ignition.

The forced ventilation can be sufficiently performed by lengthening the post-purging time when the combustion of the gas burner 2 is stopped by the combustion stopping means 26 when the incomplete combustion is detected. By making the rotation speed of the combustion fan 5 higher by the fan rotation speed control means 24 than by the combustion control means 21 when the combustion of the gas burner 2 is stopped, the combustion can be performed more reliably.

In the forced ventilation, the post-purge time when the combustion of the gas burner 2 is stopped by the combustion stopping means 26 after the incomplete combustion is detected is replaced by a fan rotation speed controlling means. 24, the number of revolutions of the combustion fan 5 may be increased by the combustion control means 21 compared to when the combustion of the gas burner 2 is stopped.

Next, the operation when an abnormality of the apparatus is detected before the igniter 18 is turned on in FIG. 4 will be described with reference to FIGS.

As shown in FIG. 4, when an abnormality of the combustion fan 5 or an abnormality of each part of the apparatus is detected in the initial state by the abnormality detecting means 25 following the start of rotation of the combustion fan 5,
At this time, since the supply of the fuel gas has not been started yet, the signal from the abnormality detecting means 25 is sent directly to the post-purge time setting means 27 without passing through the combustion stopping means 26, and the post-purge time setting means 27 5 as shown in 6
The second timer 29 is operated.

When the 5-second timer 29 times out, the fan control means 24 stops the rotation of the combustion fan 5. Next, when the operation switch is turned off, the operation of the water heater A ends.

Next, the operation when the ignition failure is detected in FIG. 4 will be described with reference to FIGS.

As shown in FIG. 4, when the abnormality detection means 25 detects an ignition failure of the gas burner 2, first, as shown in FIG. 7, it is determined whether or not the ignition failure is a predetermined number of times or more. You. If the ignition failure is, for example, twice or less, the abnormality detecting means 25 does not regard the ignition failure as an abnormality of the apparatus, and the rotation speed of the combustion fan 5 is controlled by the fan rotation speed control means 24 and the gas burner 2 is controlled by the combustion control means 21. After the combustion is stopped, the engine is rotated at a higher speed than in the case where the combustion is stopped, and fresh air is sent into the combustion chamber 1, and then the igniter O shown in FIG.
The ignition operation of N or less is repeated.

When the ignition failure exceeds two times, the abnormality detection unit 25 first detects the ignition failure as an abnormality of the apparatus and sends a signal to the combustion stopping unit 26. Then, the combustion stopping means 26 operates the proportional valve 17 and the main solenoid valve 1.
6. The combustion of the gas burner 2 is stopped by turning off the source gas solenoid valve 15 to stop the supply of the fuel gas, and a signal is sent to the post-purge time setting means 27.

When the ignition failure exceeds two times, the post-purge time setting means 27 operates the 5-second timer 29. Then, as shown in FIG. 7, when the 5-second timer 29 times out, the fan control means 24 stops the rotation of the combustion fan 5. Next, when the operation switch is turned off, the operation of the water heater A ends.

Incidentally, when an abnormality of the device such as the combustion fan 5 is detected, the device such as the combustion fan 5 may be stopped immediately.
Alternatively, the post-purge time setting means 27 must be directly connected to the fan control means 24. However, according to the present embodiment, the device such as the combustion fan 5 can be stopped within a short time of 5 seconds after the abnormality of the combustion fan 5 is detected, and the abnormality detection is substantially performed. Immediately after that, an effect equivalent to stopping the device such as the combustion fan 5 is obtained.
In addition, since the above connection is not required and an independent timer is not required for this case, the device configuration can be simplified.

Further, in this embodiment, as shown in FIG. 4, the post-purge time in the case of the normal combustion stop is set to 5 seconds. However, the re-ignition is performed within a short time after the normal combustion stop. It takes a long time for the stopped combustion fan 5 to reach the original rotation speed, and after the end of the post-purge time, the combustion fan 5 is used as a post fan for re-ignition.
May be continued for a predetermined time.

[0043]

As is apparent from the above, according to the present invention, when incomplete combustion is detected due to a decrease in the oxygen concentration in the air in the room, the post-purge time is reduced by the exhaust gas in the combustion chamber. The time is set to be sufficiently longer than the time required for discharging the gas, or when the incomplete combustion is detected and the combustion of the burner is stopped by the combustion stopping means, the combustion of the burner is stopped by the combustion control means. The air in the room can be forcibly ventilated by performing the post-purge by increasing the number of revolutions of the combustion fan as compared to when it is stopped. Therefore, when the incomplete combustion is detected due to the decrease in the oxygen concentration and the combustion device is ignited immediately after the combustion of the burner is stopped, the incomplete combustion is prevented from occurring again, and the combustion device is normally operated. Can be used.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view of a room in which a combustion device according to an embodiment of the present invention is installed.

FIG. 2 is an explanatory sectional view showing the configuration of the combustion device shown in FIG.

FIG. 3 is a block diagram showing a configuration of a main control device of the combustion device shown in FIG. 1;

FIG. 4 is a flowchart showing the operation of the combustion device shown in FIG. 1;

FIG. 5 is a flowchart showing the operation of the combustion device shown in FIG. 1;

FIG. 6 is a flowchart showing the operation of the combustion device shown in FIG. 1;

FIG. 7 is a flowchart showing the operation of the combustion device shown in FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Combustion chamber, 2 ... Burner, 5 ... Combustion fan, 21 ... Combustion control means, 22 ... CO detection means, 24 ... Fan rotation speed control means, 26 ... Combustion stop means, 27 ... Post purge time setting means, A ... Combustion device, D ... exhaust means.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F23N 5/20 101 F23N 5/24 106 F23N 5/24 108

Claims (3)

(57) [Claims] 1. A combustion chamber housing the burner, and exhaust means for exhausting exhaust gas of combustion chamber outdoors, ya the burner
A combustion fan for discharging the exhaust gas to the exhaust means while blowing air inside the combustion air, a combustion control means for controlling the combustion of the burner, CO concentration in the exhaust gas
Combustion detection means for detecting the incomplete combustion of the burner by detecting CO2 by a CO sensor, combustion stop means for stopping combustion of the burner when incomplete combustion of the burner is detected, and the combustion fan And a fan control means for performing post-purging for a predetermined time when the combustion of the burner is stopped, wherein the combustion of the burner is stopped by detecting the incomplete combustion. is when was the row time for performing port Sutopaji, a post-purge sufficient to forced ventilation indoor set sufficiently longer than the time required to discharge the exhaust gas in the combustion chamber
Indoor stationary combustion apparatus characterized by comprising providing sales is post-purge time setting means. 2. A combustion chamber housing the burner, and exhaust means for exhausting exhaust gas of combustion chamber outdoors, ya the burner
A combustion fan for discharging the exhaust gas to the exhaust means while blowing air inside the combustion air, a combustion control means for controlling the combustion of the burner, CO concentration in the exhaust gas
Combustion detection means for detecting the incomplete combustion of the burner by detecting CO2 by a CO sensor, combustion stop means for stopping combustion of the burner when incomplete combustion of the burner is detected, and the combustion fan Fan that performs a first post-purge when combustion of the burner is stopped by the combustion control means, and performs a second post-purge when the combustion of the burner is stopped by the combustion control means in indoor installation type combustion apparatus comprising a control means, the rotational speed of the combustion fan during the second post-purge, larger than the speed during the first post-purge
An indoor-installed combustion apparatus characterized by comprising fan rotation speed control means for performing post-purging sufficient to forcibly ventilate the indoor space . 3. The indoor installation type combustion apparatus according to claim 1, wherein said combustion apparatus is a gas water heater.