JPH0484021A - Device to detect trouble in kerosene burner - Google Patents

Abstract

PURPOSE:To detect for sure any troubles in a fuel supply valve and inform it by outputting a stop signal to a fuel supply valve at the time when the combustion time to the first cycle has passed and outputting a stop signal to a fuel supply pump only when no flame is detected. CONSTITUTION:In the check of troubles, at first, the stop instruction is given to fuel supply valves 24 and 34 that are open by a control section 70 when the combustion time to the first cycle has passed, and if flame detectors 23 and 33 detect no flame, it is judged that the valves 24 and 34 are normal, and at the same time the stop instruction is issued to a fuel supply pump 40. With this the first cycle combustion is finished. By the way at the time when the combustion time has passed to the first cycle, ignitors 22 and 32 are redriven, and on the other hand if the flame detectors 23 and 33 continue to detect flame in the flame detection judgment, a display signal as a trouble informing signal is outputted on the condition that the flame detection is continued for a certain time, and the display is made by a trouble display lamp 82. And the pump 40 is tuned OFF.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a petroleum oil burner equipped with two burners and capable of instantaneously heating hot water at a set temperature through on-off cycle combustion that repeats on-off cycles in relatively short cycles. The present invention relates to a water heater failure detection device.

<Prior art and its problems> Oil combustion in which oil from one common fuel supply pump is supplied to two burners through respective fuel supply on-off valves, and one or two burners are combusted as necessary. In a burner, the flame detector installed on each burner also detects the combustion flame light of the other burner, so when only one burner is burning, the fuel supply on-off valve to the other burner can be turned on and off. Even if oil leaks and combustion occurs due to a malfunction, it is possible to determine whether or not the burner on the malfunctioning side is truly malfunctioning by detecting a flame from the flame detector of the burner on the malfunctioning side. Can not.

Conventionally, the off signal from the combustion operation switch caused the fuel supply pump to stop at the same time as the fuel supply on-off valve closed, so if the combustion operation switch was turned off, even if the fuel supply valve remained open due to a malfunction. Even if it is, the fuel supply to the burner is stopped and combustion is stopped. In other words, a failure or leak in the fuel supply on/off valve could not be detected.

Therefore, in order to eliminate the above-mentioned drawbacks, the applicant has
No. 109591 provided a device for checking for failures and leaks in fuel supply on-off valves.

However, since the invention disclosed in Japanese Patent Application No. 2-109591 is a device that performs a check every time there is a command to stop combustion, a combustor that frequently turns combustion on and off has the disadvantage of excessive checking. In other words, the hot water supply system instantaneously supplies hot water at a predetermined set temperature by calculating the ratio of combustion on-time and off-time from the required amount of heat and repeating combustion on and off in relatively short cycles using that ratio. If the device were to have a mechanism that performs a check every time there is a combustion off command, the number of checks would be excessive, and if there was an afterflame during the check, the combustion on time would be extended each time. There was a problem that the on/off ratio deviated from the calculated value and the hot water tap temperature shifted to the higher temperature side, resulting in poor hot water tap characteristics.

Therefore, the present invention solves the above-mentioned conventional problems, and provides an instantaneous two-bin type oil water heater using on-off cycle combustion that does not deteriorate the hot water output characteristics, and also reliably detects leakage due to failure of the fuel supply on-off valve. The purpose of the present invention is to provide a failure detection device that can perform the following tasks.

<Means for Solving the Problems> In order to achieve the above object, the failure detection device for an oil combustor of the present invention includes two burners each equipped with a fuel supply on-off valve and a flame detector; It has at least a common fuel supply pump for sending petroleum through the fuel supply on-off valve and a control unit that controls the operation of each part of the water heater, and the setting is made by on-off cycle combustion that repeats on and off in relatively short cycles. This is a failure detection device for an oil water heater that instantaneously supplies hot water at a temperature of In addition to outputting a closing signal, a stop signal for the fuel supply pump is output after waiting for a flame non-detection signal from the flame detector to be input, and a flame non-detection signal from the flame detector is output after a certain period of time has elapsed. The first feature is that it is configured to output a late N notification signal if no input is made.

Furthermore, in addition to the first feature described above, the oil combustor failure detection device of the present invention does not input a flame non-detection signal from the flame detector even after a certain period of time has elapsed after the output of the closing signal of the fuel supply on-off valve. In this case, the second feature is that the control section is configured to output a cycle combustion stop signal as well.

<Operation> According to the first feature of the present invention, if there is no failure in the fuel supply on-off valve, the fuel supply on-off valve reliably closes the fuel supply path by the closing signal of the fuel supply on-off valve, so that the fuel supply on-off valve reliably closes the fuel supply path. Even if an afterflame may remain for some time, the fire is extinguished reliably, and the fuel supply pump is stopped via the control section in response to a flame non-detection signal from the flame detector. On the other hand, if the fuel supply on-off valve is malfunctioning, the fuel supply on-off valve will not be able to close the path even with the close signal of the fuel supply on-off valve, so fuel from the fuel supply pump that is still in operation will continue to fail. The fuel is sent to the burner through the on-off valve, where it continues to burn. Therefore, the flame detector continues to output a flame detection signal, and as a result of not inputting a flame non-detection signal for a certain period of time or more, the control section determines that the fuel supply on-off valve has failed and outputs a failure notification signal. This allows the user to know if the fuel supply on/off valve is out of order.

In particular, since the failure check of the fuel supply on-off valve accompanied by the closing signal of the fuel supply on-off valve is performed every time the on-off cycle combustion is started, the failure check of the fuel supply on-off valve can be reliably performed. Moreover, the failure check of the fuel supply on-off valve is limited to the time when the combustion time of the first cycle has elapsed after the start of on-off cycle combustion, so even if the combustion time is extended during the check, it will only occur during the first cycle. It is limited to the following cases and does not occur after the second time. Therefore, the pre-calculated ratio of on time and off time can be maintained,
This prevents the tapping temperature from shifting to a higher temperature side.

According to the second feature of the present invention, in addition to the effect of the first feature, if there is a failure in the fuel supply on-off valve, on-off cycle combustion can be stopped to ensure safety.

<Example> Fig. 1 is an overall configuration diagram of an apparatus implementing the present invention, Fig. 2 is a flowchart showing an example of timing control operation of failure check of the fuel supply on/off valve by the control unit, and Fig. 3 is a flowchart showing an example of the timing control operation of the fuel supply on/off valve by the control unit. FIG. 4 is a flowchart showing an example of control operation when checking for valve failure, and FIG. 4 is an operation timing chart of each part during on-off cycle combustion.

Two gun-type burners 20.30 face the combustion chamber 11 of the combustion canister IO. The upper burner 20
is a small burner, which will be referred to as the first burner 20.

Further, the lower burner 30 is a large burner, and is used as a second burner. The first burner 20 and the second burner 30 each have
First and second jet nozzles 21.3I, first and second igniters 22.32 for ignition, first and second flame detectors 23
．． 33, and first and second fuel supply on-off valves 24 and 34. Fuel is sent to the first and second jet nozzles 21.31 from a common fuel supply pump 40 via first and second fuel supply on-off valves 24.34, respectively. 5
0 is a blower fan.

A heat exchanger 60 for hot water supply is provided in the combustion chamber 11,
A water inlet pipe 61 and a hot water outlet pipe 62 are connected. Water inlet pipe 61
is provided with a water quantity sensor 63, and when this water quantity sensor 63 detects a certain minimum operating water quantity (MOQ) or more, it inputs the detection signal to the control unit 70.

The operation of each part of the device is controlled by a control section 70. That is, the control unit 70 has a built-in microcomputer, inputs commands from a remote controller (hereinafter referred to as remote control) 80, and signals from the flame detector 23.33, water amount sensor 63, etc., and controls the igniter 22.32, fuel supply, etc. Operation commands are output to the on-off valves 24 and 34, the fuel supply pump 40, the ventilation fan 50, and the like.

The remote control 80 is provided with at least a hot water supply operation switch 81 and a failure indicator lamp 82. When the hot water supply operation switch 81 is turned on, the control unit 70 causes one burner 20, 30 or both burners to undergo on-off cycle combustion on the condition that the water flow sensor 63 detects the minimum operating water flow (MOQ). .

That is, the control unit 70 calculates the required amount of heat from the set hot water supply temperature, incoming water temperature, and incoming water flow rate, determines which burner or both burners to use, and calculates the amount of heat per unit time of the selected burner. The ratio of the on time and off time of the burner is determined from the calorific value and the required heat amount, and on-off cycle combustion is performed in which on and off cycles are repeated in a relatively short period of time (for example, 3 seconds to 10 seconds).

In the on-off cycle combustion, when the operation switch 81 is turned on, the user opens a door (not shown) of the hot water outlet pipe 62, and the water flow sensor 63 detects the minimum operating water flow or more, the control unit 70 first activates the igniter 22. 32, then after a slight time lag, turn on the fuel supply on/off valve 24.34.
This is done by opening the fuel supply pump 40 and driving the fuel supply pump 40.

The on-off cycle combustion is stopped when the water flow sensor 63 becomes lower than the minimum operating water flow due to the user closing the valve, the fuel supply on/off valve 24, 34,
This is done by closing the pump 40.

Furthermore, during on-off cycle combustion, the combustion stop in each cycle after the second cycle is controlled by the fuel supply on/off valve 24.3.
4 and pump 40 are turned off at the same time (see FIG. 4).

On the other hand, during on-off cycle combustion, combustion stops in the first cycle when the control section 70 first issues a command to close the fuel supply on-off valve 24.34 as the combustion time elapses, and the flame detector 23.33 starts to stop the combustion. This is done by outputting a stop signal for the pump 40 when the control unit 70 inputs the non-detection signal (see FIG. 4).

The operation control by the control section 70 for checking the failure of the fuel supply on-off valves 24, 34 will be further explained with reference to FIGS. 2 to 4.

Now, when the operation switch 81 of the remote control 80 is turned on (
Step 101), the water flow sensor 63 detects the minimum operating water flow (M
O, Q) or more (Step 1)
02), the control unit 70 starts on-off combustion. When the first cycle of combustion occurs (step 104), a failure check is performed (step 105). If the combustion is not in the first cycle, no failure check is performed. If the result of the failure check is normal, combustion continues from the second cycle onwards (step 107). If there is a failure in the on-off valve 24.34, combustion is stopped as a safety operation (step 108).
). Minimum operating water quantity (MOQ) during cycle combustion
When it becomes less than (step 109), cycle combustion is stopped (step 110).

In the failure check, when the combustion time of the first cycle has elapsed (step 201), the control unit 70 issues a command to close the fuel supply on-off valves 24 and 34, which are open (step 202), and the flame detector If no flame is detected at 23.33 (step 203), it is determined to be normal and a command to stop the fuel supply pump 40 is issued (step 204).

This completes the first cycle combustion.

In addition, when the combustion time of the first cycle has elapsed, the igniter 2
2.Redrive the 32 (see Figure 4). On the other hand, in the flame detection determination at step 203, the flame detectors 23.33
If the flame detection continues, a display signal is output as a failure notification signal and a display 206 is performed by the failure indication lamp 82 on the condition that flame detection continues for a certain period of time T (step 205). Then turn off the pump 40 (step 2
07).

The certain time T takes into consideration the afterflame that may occur when the fuel supply on/off valve 24, 34 is closed, and is set to be longer than the time of the afterflame that may occur.

Note that if there is an afterflame, the combustion on time will be extended by that amount from the calculated time.

No check is performed as the combustion time elapses in each cycle after the second cycle. In that case, the fuel supply on-off valve 24.34 and the pump 40 are closed at the same time, and the igniter 22.32 is not driven.

In addition, in the above, cycle combustion is performed with both burners at 20.30
When using burner failure, it is only known that one of the burners is malfunctioning. If only one of the burners is used for cycle combustion, failure of that burner is certain.

<Effects> The present invention has the above configuration, and according to the oil water heater failure detection device according to claim 1, when the combustion time of the first cycle has elapsed, a closing signal is first output to the fuel supply opening/closing valve. Since the fuel supply pump stop signal is output after waiting for flame detection, if there is a failure in the fuel supply on/off valve, this can be detected reliably and this can be reported. can. Moreover, since the check for the presence of a failure is always performed when on-off cycle combustion is performed, the failure check can be performed reliably. Furthermore, since the check for the presence of a failure is limited to the first cycle of the on-off cycle, the number of checks is not excessive, and problems with hot water dispensing characteristics such as shifting the combustion on time to a longer period do not occur.

Furthermore, according to the oil water heater failure detection device according to claim 2, in addition to the effects achieved by the configuration according to claim 1, cycle combustion is stopped when there is a failure in the fuel supply on-off valve. , safety can also be ensured.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of an apparatus implementing the present invention, Fig. 2 is a flowchart showing the timing control operation of a failure check of the fuel supply on-off valve by the control unit, and Fig. 3 is a flowchart showing the timing control operation when the control unit checks for failure of the fuel supply on-off valve. A flowchart showing an example of control operation, and FIG. 4 is an operation timing chart of each part during on-off cycle combustion. 20.30: Base 22.32: Igniter 23.33: Flame detector 24.34: Fuel supply on/off valve 40: Fuel supply pump 63: Water flow sensor 70: Control unit 80: Remote controller 81: Hot water supply operation switch 82 : Malfunction indicator lamp

Claims (2)

[Claims] (1) Two burners each equipped with a fuel supply on-off valve and a flame detector, a common fuel supply pump for sending oil to the burners via the fuel supply on-off valve, and a water heater for each part. A failure detection device for an oil water heater that instantaneously supplies hot water at a set temperature by on-off cycle combustion that repeatedly turns on and off in a relatively short cycle, the device having at least a control section that performs operation control. When the combustion time of the first cycle has elapsed due to the start of cycle combustion, the control section first outputs a closing signal for the fuel supply on-off valve, and waits for input of a flame non-detection signal from the flame detector to switch off the fuel. A petroleum hot water heater characterized in that it is configured to output a stop signal for the supply pump, and to output a failure notification signal if a flame non-detection signal from the flame detector is not input even after a certain period of time has elapsed. equipment failure detection device. (2) If the flame non-detection signal from the flame detector is not input even after a certain period of time has elapsed after outputting the closing signal of the fuel supply on/off valve, the control unit will also output a cycle combustion stop signal. A failure detection device for a petroleum water heater according to claim 1, configured.