JP2619205B2 - Combustion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to combustion equipment such as a water heater,
In particular, the present invention relates to a combustion device provided with means for detecting incomplete combustion in a combustion section by an unburned gas sensor such as a CO sensor.

[0002]

2. Description of the Related Art Conventionally, in this type of apparatus, an unburned gas sensor for detecting unburned gas such as CO is provided in an exhaust passage connected to a combustion chamber of a water heater, for example. It is known that an incomplete combustion state is detected based on the output of the corresponding unburned gas sensor, and the combustion operation is stopped by this, and in this type, when the output of the unburned gas sensor exceeds a predetermined determination level, It is determined that an incomplete combustion state has occurred.

An incomplete combustion state in which the output of the unburned gas sensor exceeds a predetermined determination level includes an incomplete combustion state caused by blockage of an exhaust passage and an air supply passage, clogging of fins, and the like, and a combustion chamber of a water heater. There is an incomplete combustion state in which strong air is blown into the combustion chamber and the air supply to the combustion chamber is obstructed, and the former incomplete combustion state causes clogging of exhaust passages and air supply passages, clogging of fins, etc. Unless excluded
Although not resolved, the latter incomplete combustion condition is generally temporary and resolves spontaneously. It is desirable that the combustion operation be stopped when the former incomplete combustion state occurs, and that the combustion operation be continued when the latter incomplete combustion state occurs.

However, in the prior art, the output of the unburned gas sensor is not distinguished between a continuous incomplete combustion state caused by blockage of the exhaust passage and the air supply passage and a temporary incomplete combustion state caused by wind and the like. Is designed to stop the combustion operation when it exceeds a predetermined determination level. Therefore, there is a disadvantage that the combustion operation is originally stopped when it is not necessary to stop the combustion operation.

In order to eliminate such inconvenience, the combustion operation is stopped when an incomplete combustion state in which the output of the unburned gas sensor exceeds a predetermined determination level is continuously detected for a predetermined time. If the detection of the incomplete combustion state is shorter than the predetermined time, the combustion operation may be continued. Further, when a continuous incomplete combustion state is detected, it is conceivable to disable the restart of the combustion equipment and urge the user to request a repair.

However, even in such a case, the incomplete combustion state may continue to some extent due to, for example, a continuous wind longer than the predetermined time. In such a case, the combustion equipment It is desirable to be able to restart.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and it is possible to eliminate the erroneous stop of the combustion operation due to an incomplete combustion state due to the influence of wind, etc. An object of the present invention is to provide a combustion device that operates properly in an incomplete combustion state due to blockage or the like.

[0008]

According to the present invention, there is provided a combustion apparatus provided with an incomplete combustion detecting means for detecting incomplete combustion in a combustion section. The operation control means for stopping the combustion operation of the combustion equipment so that the combustion operation can be restarted when incomplete combustion is detected continuously for the timer time, and restarting after stopping the combustion operation due to the incomplete combustion were repeated. A timer time setting means for setting the timer time according to the number of repetitions, the timer time setting means setting the timer time shorter as the number of repetitions increases. is there.

[0009]

According to the present invention, when the incomplete combustion is detected by the incomplete combustion detection means for a predetermined timer period continuously, the operation control means stops the combustion operation of the combustion equipment in a restartable manner. Is done. On the other hand, in a temporary incomplete combustion state shorter than the timer time due to the influence of wind or the like, the combustion operation is continued. Further, even in the case of the influence of wind, etc., the combustion device is temporarily stopped in a temporary incomplete combustion state longer than the timer time, but the combustion operation is restarted without any trouble by restarting the combustion device. Further, in a continuous incomplete combustion state due to a blockage of the exhaust passage or the like, although the combustion operation is restarted by restarting the combustion equipment, at this time, the timer time is shorter than the previous timer time by the timer time setting means. Since the setting is set, the combustion operation is stopped in a shorter time than the previous operation, and if this operation is repeated, the operation is finally stopped immediately after the restart of the combustion operation. Accordingly, when a continuous incomplete combustion state occurs due to a blockage of the exhaust passage or the like, it is possible to reliably prompt the user to request a repair or the like.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory sectional view of a water heater provided with the present embodiment,
FIG. 2 is a block diagram of a main part of FIG. 1, and FIG. 3 is a flowchart for explaining the operation of the present embodiment.

As shown in FIG. 1, a forced combustion gas water heater A includes a gas burner 2 that burns in a combustion housing 1.
(Combustion section), and the blower fan 3 supplies the combustion air X of the gas burner 2 to the combustion housing 1. Also,
In the water heater A, the combustion control device 4 supplies gas to the gas burner 2, ignites the gas burner 2, and controls the combustion fan 3.

The combustion housing 1 is provided with combustion air X downward.
, And a discharge port 6 for discharging the combustion exhaust gas Z to the outside is provided above. Also, the combustion housing 1
A heat exchanger 7 is arranged above the gas burner 2 in the inside.

The gas burner 2 includes a burner group 8 for forming a flame, and a nozzle tube 10 located below the burner group 8 and having an ejection port 9. The fuel gas Y is supplied to the gas burner 2 through the gas pipe 11. The blower fan 3 has turbo-type blades.

The combustion control device 4 includes a water regulator 12, a water sensor 13, a thermistor 14, an original gas solenoid valve 15, a main solenoid valve 16, a governor gas proportional solenoid valve 17, an igniter 18, a frame rod 19, and a CO sensor. 20 and a controller 21 for controlling them. Controller 2
As shown in FIG. 2, a combustion control means 22 (operation control means), a CO sensor control means 2
3. Incomplete combustion determination means 24 and timer time setting means 2
5 is a microcomputer including: CO sensor 2
0 and incomplete combustion determination means 24 are incomplete combustion detection means 2
6 is constituted.

Next, the controller 21 of the combustion control device 4
Will be described with reference to FIG.

When a hot water tap (not shown) is opened while an operation switch (not shown) is turned on, the controller 21 detects this by a water amount sensor 13 and controls the blower fan 3 by a combustion control means 22. The fuel gas is supplied to the gas burner 2 by driving the igniter 18 and operating the igniter 18 and opening the original gas solenoid valve 15, the main solenoid valve 16, and the proportional solenoid valve 17 to ignite the gas burner 2. Then, the combustion operation of the water heater is started. At this time, when the gas burner 2 is ignited, the ignition is detected by the frame rod 19, and if the ignition by the operation of the igniter 18 is not detected, the igniter 18 and the original gas solenoid valve 15 are turned off to operate the water heater. To stop.
When the ignition is detected, the igniter 18 is turned off, then the proportional control of the gas amount is performed by the proportional solenoid valve 17, and the CO sensor 20 is energized by the CO sensor control means 23 to start it. An incomplete combustion detection operation to be described later is performed by the sensor 20 and the incomplete combustion determination means 24 and the like. The gas amount proportional control and the incomplete combustion detection operation are continuously performed until the hot water tap is closed. In addition, CO
The operation of the sensor 20 may be started at the time when the ON signal is output from the water amount sensor 13 or at the time when a predetermined time has elapsed after detecting the flame.

When the hot water tap is closed, the controller 21 detects this by the water quantity sensor 13 and the combustion control means 22 causes the original gas solenoid valve 15, the main solenoid valve 16,
By controlling the proportional solenoid valve 17 to close, the gas burner 2 is extinguished, the driving of the combustion fan 3 is stopped, and the CO sensor 20 is turned off, thereby stopping the combustion operation of the water heater.

Next, the operation of detecting incomplete combustion will be described in detail with reference to FIG.

The basic operation of this incomplete combustion detection operation will be described. The controller 21 determines that the CO concentration (CO value) detected by the output of the CO sensor 20 corresponds to the incomplete combustion state of the gas burner 2. The combustion operation is stopped when the state of being equal to or more than the predetermined determination value has continued for a predetermined timer time (detection timer time) set at the start of the combustion operation.

More specifically, when the combustion operation starts, CO
When the sensor 20 is started, first, the detection timer time is set by the timer time setting means 25 in accordance with the value of a parameter K indicating the number of repetitions of restart described later, and is given to the incomplete combustion determination means 24. You. In this case, at the time of the first operation of the water heater, the value of the parameter K is initially set to “0”, and at this time, the detection timer time is set to, for example, three minutes.

During the combustion operation, when the CO value detected by the output of the CO sensor 20 exceeds a predetermined judgment value (for example, a CO concentration of 2000 ppm) due to incomplete combustion, the incomplete combustion judgment means 24 The built-in detection timer 24a (see FIG. 2) is started according to the detection timer time.

The state in which the CO value is equal to or greater than the predetermined determination value continues for the detection timer time and the detection timer 24a times out.
Controls the combustion control means 22 to close the source gas solenoid valve 15, the main solenoid valve 16, and the proportional solenoid valve 17 to extinguish the gas burner 2 and stop driving the combustion fan 3; Is turned off, thereby stopping the combustion operation of the water heater. Further, the value of the parameter K is increased by "1".

When the incomplete combustion state continues for the detection timer period and the combustion operation is stopped, the water heater of this embodiment is restarted by, for example, turning on an operation switch (not shown) again. The restarting restarts the combustion operation as described above. When the combustion operation restarts, the detection timer time of the detection timer 24a is newly set according to the value of the parameter K at that time.

The parameter K indicates the number of repetitions of restarting when the combustion operation is stopped while the incomplete combustion state continues for the detection timer time. The detection timer time has a large value of the parameter K. In other words, it is set to be shorter as the number of repetitions of restarting when the combustion operation is stopped due to incomplete combustion increases. More specifically, the detection timer time is, for example, 3 minutes when the number K of restarts is "0", 2 minutes when K = 1, and 1 minute when K = 2. , K = 3, it is set to 0 minutes.

Thus, when the incomplete combustion state (CO value ≧ judgment value) is not a temporary one caused by wind, but a continuous one caused by blockage of the introduction port 5 and the exhaust port 6, etc. When the restart of the water heater is repeated, each combustion operation time (detection timer time) gradually decreases,
Eventually, after the restart, the combustion operation stops immediately. Then, the user can recognize that the inlet port 5 and the exhaust port 6 are clogged and the repair is necessary by stopping the combustion operation immediately after the restart.

On the other hand, referring to FIG. 4, in the incomplete combustion detection operation, the time within the detection timer time (detection timer 2
If the CO value becomes smaller than the judgment value before the time-out of 4a, the incomplete combustion judgment means 24 stops the detection timer 24a and clears the value of the parameter K ("0"). To). Therefore, when the incomplete combustion state (CO value ≧ determination value) occurs temporarily due to a temporary wind or the like, the combustion operation of the water heater continues without stopping. The same applies to the combustion operation by restart. Also, if the incomplete combustion state due to wind or the like continues for more than the detection timer time, the combustion operation is temporarily stopped at that time, but it is generally not possible that such a wind or the like continues for a long time. Since it cannot happen, the combustion operation can be restarted without any trouble by restarting.

The present invention is not limited to the above embodiment, but can be appropriately modified without departing from the gist of the present invention. For example, in the present embodiment, a water heater has been described as an example of a combustion device, but it is needless to say that the present invention can be applied to a combustion device such as a fan heater.

[0028]

As is clear from the above description, according to the present invention, the combustion operation of the combustion equipment is restarted when the incomplete combustion detecting means detects incomplete combustion for a predetermined timer period. The timer time is set to be shorter as the number of repetitions increases when restarting after stopping the combustion operation due to the incomplete combustion is repeated. In addition to the erroneous operation in which the combustion operation is stopped when a temporary incomplete combustion state occurs due to the above, even if the combustion operation is stopped due to the effect of wind or the like that continues to some extent, restarting does not hinder combustion. Operation can be resumed. Further, when continuous incomplete combustion occurs due to blockage of the exhaust passage or the like, the combustion operation can be reliably stopped, and the timer time is reset when such continuous incomplete combustion occurs. By shortening each time the restart of the combustion equipment is repeated, the need for repair can be recognized by the user. Therefore, it is possible to provide a combustion device that performs an appropriate operation in accordance with various situations of occurrence of incomplete combustion.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view of a water heater to which an embodiment of the present invention is applied.

FIG. 2 is a block diagram of a main part of FIG. 1;

FIG. 3 is a flowchart for explaining the operation of the water heater of FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the water heater of FIG. 1;

[Explanation of symbols]

22: combustion control means (operation control means), 25: timer time setting means, 26: incomplete combustion detection means.

Claims (1)

(57) [Claims] 1. A combustion apparatus provided with incomplete combustion detection means for detecting incomplete combustion in a combustion section, wherein the incomplete combustion detection means detects incomplete combustion for a predetermined timer period. Operation control means for stopping the combustion operation of the combustion equipment so that the combustion operation can be restarted, and a timer time for setting the timer time according to the number of repetitions when restarting after stopping the combustion operation due to the incomplete combustion is repeated. Combustion equipment, comprising: setting means, wherein the timer time setting means sets the timer time shorter as the number of repetitions increases.