JP2001065902A - Gas water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas water heater to facilitate analysis of the cause of abnormality which has no reproducibility. SOLUTION: This operation state memory device 6 has a function to store the inputted state of each sensor 4 and the state of the control output of a control device 2 during a past given time. When the control device 2 detects abnormality, the device performs an output to an error code display part 5 and simultaneously stops rewriting of information stored at the operation state memory device 6. Thus, with this state, by reading information stored at the operation state memory device 6, the state of each sensor 4 at a time when a trouble occurs and at a given time before the occurrence of the trouble and the state of the output command of the control device 2 are detected. This constitution facilitates analysis of the cause of the occurrence of abnormality based on the above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas type hot water supply apparatus for supplying water to a hot water tap, a bathtub, an indoor heating device and the like by heating water by the heat of combustion of gas to produce hot water.

[0002]

2. Description of the Related Art Gas water heaters are widely used in ordinary households by heating water by the heat of combustion of gas to produce hot water and supplying the hot water to hot water taps, bathtubs, indoor heating devices, and the like. The simplest type is a completely manual type, in which a person manually ignites a pilot flame by manually operating an ignition device, visually confirms ignition, and then opens a hot water tap. When the hot water tap is opened, the flow of water is confirmed by the water flow sensor or the water pressure sensor, the gas shutoff valve is opened, gas is supplied to the burner, and the gas is ignited by the flame from the pilot flame. Then, the water in the heat exchanger is heated and supplied as hot water from a hot water tap.

However, in recent years, the type of hot water supply apparatus has been upgraded, and an automatic control type hot water supply apparatus which receives input from various sensors and controls the hot water supply temperature, combustion control, and safety confirmation is used. It is becoming. An example is shown in FIG.

A gas burner 1 is provided in a water heater main body 11.
2 and a heat exchanger 13 are provided, and water in the heat exchanger 13 is heated by combustion heat of the gas burner 12. When the water tap is opened, the water filter 1
The water is supplied to the heat exchanger 13 via 4. Since this water amount is detected by the water amount sensor 15, a control device (not shown) in the electrical board opens the original gas solenoid valve 16 and applies a voltage to the ignition plug, and the spark generates gas to generate gas. Ignite. As a result, the gas from the combustion tube 18 burns and heats the water in the heat exchanger 13.

[0005] The water supply flow rate is controlled by a water flow control valve 19,
The hot water supply temperature is detected by a tapping water thermistor 20 to control the opening degree of the bypass water amount control valve 21 or to control the gas proportional valve 22.
The target temperature is maintained by controlling the degree of opening. For this control, the temperature of the supply water detected by the incoming water thermistor 23 and the temperature of the hot water at the outlet of the heat exchanger 13 detected by the still water thermistor 24 are simultaneously used. When the target hot water temperature is significantly different or the water supply amount is significantly different and cannot be controlled by the opening degree of the bypass water amount control valve 21 or the gas proportional valve 22, the gas burner is opened and closed by opening and closing the capacity switching gas solenoid valve 25. To greatly change the combustion capacity of

The combustion air is supplied from the combustion fan 26 to the gas burner 12. A rotation speed sensor 27 of the combustion fan 26 is provided to detect whether or not combustion air is being supplied. This rotation speed sensor 27
In addition, it is used to control the number of revolutions of the combustion fan 26 so as to supply an air flow corresponding to the gas amount.

As a safety device, an overheat prevention sensor 28 for detecting overheating of the water heater main body, an overpressure prevention safety device 29 for detecting overpressure in the heat exchanger 13 and the hot water supply pipe and preventing it by draining, An embers safety device 3 that is provided immediately adjacent to the heat exchanger 13 and detects overheating of the heat exchanger 13 due to embers.
0, an electric leakage safety device 31 for detecting electric leakage, a flame detector 32 for detecting gas combustion flame, and the like.

FIG. 4 is a schematic flowchart showing the main operation of the control device in the electrical board. Step S01
In step S02, it is checked whether or not the electric leakage safety device is inoperative when the power is turned on by a human. If it is not operating, it is normal, so that it is possible to shift to step S03. When the human turns on the operation switch in step S03, the operation state is entered. In this state, the control device shifts to the state of step S05, and checks whether or not the water amount sensor is turned on. Step S0
If the person turns the hot water tap "open" in step 4, the water amount sensor is turned on in step S05, and the process proceeds to step S06.
Until the person turns the hot water tap "open", the water level sensor turns off.
Since it is F, it stands by in the state of step S05.

In step S06, it is checked whether or not the sensors of various safety devices are normal. When all the sensors indicate normal values, the combustion fan is turned on in step S07. Then, in step S08, the value of the rotation speed sensor of the combustion fan is checked to determine whether the rotation speed is normal. If the number of rotations is normal, the ignition device is turned on in step S09. As a result, a spark is generated from the spark plug. Then, the process proceeds to step S10, where the original gas solenoid valve and the gas proportional valve are turned on (open).
And Then, the signal from the flame detector is checked in step S11, and when "flame detection" is detected, it is determined that ignition has been confirmed, and the process proceeds to step S12 to turn off the ignition device. Then, the process proceeds to step S13, in which proportional control of the gas amount and the air amount is performed so that the target hot water temperature is obtained and complete combustion is performed. This is a steady hot water supply state.

In the steady hot water supply state, step S14
To monitor the non-operation of the safety device. If not, the process proceeds to step S15 to check whether or not the water amount sensor is turned off. If the water amount sensor has not been turned off, the process returns to step S13, and the control of the steady hot water supply state is continued.

When a person closes the hot water tap or stops supplying water for other reasons, it is detected in step S15 that the water amount sensor has been turned off. The valve and the gas proportional valve are turned off ("closed"), the combustion fan is turned off in step S17, and the process returns to the initial state, step S04.

When the safety device operates in the steady hot water supply state, the process jumps from step S14 to step S18, an error is displayed, and in step S19, the original gas solenoid valve and the gas proportional valve are turned off ("closed"). In step S20, the combustion fan is turned off. In this state, the human observes the error display and turns on the hot water tap in step S21, and turns off the operation switch in step S22. Then, the error display S23 is turned off in step S23.
In this state, a human turns off the power in step S24, and the cause is removed in step S25. When it is determined that the cause has been eliminated, the human returns to step S01 and turns on the power again.

In step S06, when an abnormality of each safety device sensor is found, the flow shifts to step S26 to display an error, and then shifts to step S21.

If it is determined in step S08 that the rotational speed of the fan is abnormal, the flow proceeds to step S27 to display an error, and then proceeds to step S20.

In step S11, if no flame is detected during a predetermined time, it is determined that ignition has failed, and re-ignition is performed. That is, the ignition device is turned off in step S28.
In step S29, the source gas solenoid valve and the gas proportional valve are turned off ("closed"). Then, in step S30, it is determined whether the number of re-ignition attempts is less than or equal to a predetermined number n. If the number is equal to or less than n, the process returns to step S08 and the ignition operation is repeated. If the number of times exceeds n, it is determined that the ignition system is defective, an error is displayed in step S27, and the process proceeds to step S21.

The above flow chart shows a very schematic flow. Actually, there are many other control routines for ensuring safety, control of hot water supply and adjustment of bypass water flow. A number of control routines are included, such as control of hot water supply temperature using a valve, control of a capacity switching gas solenoid valve, and the like.

The outputs of the overheat prevention device, the residual fire safety device, the overpressure prevention safety device and the like are connected to a safety device constituted by hardware in addition to the safety control using the above control device. Even if the control device itself becomes defective, it does not lead to an accident such as a fire.

The hot water supply apparatus shown in FIG. 3 is referred to as a one-can-one-water-channel type, which is the simplest one having one heat exchanger and one hot-water supply channel in one water heater. A two-can, two-channel system with two heat exchangers and two hot water supply systems (for example, for hot water supply to a hot water tap and for reheating a bath) in one water heater, one heat exchanger and two water supply systems There are various types such as a one-can two-water-channel type having the following. The “gas type hot water supply device” referred to in this specification includes all of these types of hot water supply devices.

[0019]

As described above,
In an automatic gas water heater, when an abnormality is detected, the content of the abnormality is displayed as an error code or the like. However, although the details of the abnormality can be understood by looking at the error code, the cause of the abnormality is unknown. Therefore, when the maintenance staff performs the repair work, if the error is reproduced, the cause can be found and the repair can be performed, but it occurs only occasionally and is reproduced when the maintenance staff performs the repair work In the case of an abnormality that does not occur, there is a problem that it is difficult to determine the cause.

The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a gas-type hot water supply apparatus which can easily analyze the cause of an abnormality having no reproducibility. I do.

[0021]

A first means for solving the above-mentioned problem is a gas-type hot water supply device which is controlled by a control device and heats water by the heat of combustion of gas to supply hot water. A gas water heater (claim 1), comprising a storage device for storing a state of each sensor and a state of a command output to each actuator during the occurrence and during a predetermined time before the occurrence of an abnormality. is there.

In this means, the state of each sensor and the state of command output to each actuator during the occurrence of an abnormality and during a predetermined time period before the occurrence of the abnormality are stored. It is possible to know the working situation of each sensor until the occurrence of the abnormality and the state of the command to the actuator, thereby making it easy to analyze the cause of the abnormality. Note that the sensors and actuators to be stored are not necessarily all sensors and all actuators, and only those related to assumed abnormalities can be appropriately selected.

A second means for solving the above-mentioned problem is:
The first means, wherein the storage device also stores an environmental state at the time of occurrence of an abnormality and during a predetermined time before the occurrence of the abnormality (claim 2).

In this means, since the environmental state (temperature, humidity, wind direction, wind speed, etc.) is stored in addition to the state of the sensor and the actuator, the cause of the abnormality can be more easily analyzed.

A third means for solving the above-mentioned problem is:
The first means or the second means, wherein contents stored in the storage device when an abnormality occurs are stored as they are until a special input is made ( Claim 3).

In this means, when an abnormality occurs, once the information during the abnormality occurrence and during a predetermined time before the occurrence of the abnormality is stored, the abnormality is reset and the operation of the gas water heater is newly started. Even if the information is stored, the stored information is stored as it is. Therefore, in the case of an abnormality with no reproducibility, even if a maintenance person arrives after the use of the gas water heater is resumed, the maintenance person can grasp the situation at the time of occurrence of the abnormality.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows Embodiment 1 of the present invention.
It is a block diagram showing an example. In FIG. 1, 1 is a gas-type hot water supply device main body, 2 is a control device, 3 is each actuator,
Reference numeral 4 denotes each sensor, 5 denotes an error code display unit, and 6 denotes an operation state storage device.

As described in the description of the prior art, the control device 2 outputs a command output to each actuator 3 based on an input from each sensor 4 to perform various controls such as hot water supply temperature control and hot water supply flow rate control. Perform safety control. When an abnormality is detected, an error code corresponding to the error is displayed on the error code display unit 5.

In this embodiment, in addition to the functions of these conventional gas water heaters, an operating state storage device 6 is provided.
Is provided. The operation state storage device 6 has a function of storing the input state of each sensor 4 and the control output state of the control device 2 until a predetermined time in the past. When detecting an abnormality, the control device 2 outputs the error code to the error code display unit 5 and stops rewriting the information stored in the operation state storage device 6 at the same time.

Therefore, by reading the information stored in the operation information storage device 6 in this state, the state of each sensor 4 and the state of the output command of the control device 2 at the time of occurrence of the failure and at a predetermined time before that can be known. . Therefore, it is easy to analyze the cause of the abnormality based on the information. Although not shown, environmental conditions such as temperature, humidity, wind direction, and wind speed are stored together with the information as necessary. By doing so, it becomes easier to analyze the cause of the abnormality.

FIG. 2 shows an example of the configuration of the operating state storage device 2. In this example, input 1 to input 10
Are stored in the corresponding first-stage storage elements. The storage elements are provided from the first stage to the n-th stage. When there is a shift command input every unit time, the input is stored in the first stage storage element and the i-th stage ( The information stored in (i = 1 to n-1) is i
It is shifted to the + 1st storage element. The shift command is output from the control device 2. When the control device 2 detects an abnormality, the control device 2 stops outputting the shift command.
Therefore, the state of each input at the time of occurrence of the failure and up to a predetermined time before that remains in the operation state storage device 2.

After the occurrence of an error, the control device 2 is reset and the operation may be restarted. This tendency is particularly large for an infrequent and non-reproducible abnormality. In such a case, the shift command is issued again from the control device 2, and the stored contents are updated and lost. Therefore, when the maintenance person arrives, the information at the time of the abnormality is lost, and it becomes difficult to analyze the failure.

In order to cope with such a situation, even if the control device 2 is reset after the occurrence of an abnormality, it is necessary that the shift command is not issued from the control device 2 unless a special input is made. desirable. In this way,
Even if maintenance personnel arrive after the water heater has been used again,
The situation at the time of occurrence of the abnormality can be read from the operation state storage device 6, and the cause of the abnormality can be analyzed.

When the control device is reset, the power supplied to the entire hot water supply device may be cut off. Assuming such a case, it is preferable that the storage elements constituting the operation state storage device 6 be rewritable and that the stored contents are not lost even when the power is turned off.

[0035]

As described above, according to the first aspect of the present invention, the operation status of each sensor and the status of the command to the actuator can be known until the occurrence of an abnormality. This makes it easy to analyze the cause of the abnormality.

According to the second aspect of the present invention, by storing the environmental conditions together, it becomes easier to analyze the cause of the abnormality.

According to the third means for solving the above-mentioned problem, even when the maintenance staff arrives after the use of the gas water heater is resumed, the maintenance staff can grasp the situation at the time of occurrence of the abnormality.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of a configuration of an operation state storage device.

FIG. 3 is a schematic diagram showing an example of a gas hot water supply apparatus.

FIG. 4 is a flowchart showing an example of the operation of the control device of the gas hot water supply apparatus.

[Description of Signs] 1 ... Gas-type hot water supply main unit 2 ... Control device 3 ... Each actuator 4 ... Each sensor 5 ... Error code display unit 6 ... Operating state storage device

Claims (3)

[Claims] 1. A gas type hot water supply device controlled by a control device to heat water by the heat of combustion of gas to supply hot water. A gas hot water supply device comprising a storage device for storing a state of a command output to each actuator. 2. The gas type hot water supply apparatus according to claim 1, wherein the storage device additionally stores an environmental state at the time of occurrence of an abnormality and during a predetermined time before the occurrence of the abnormality. Gas water heater. 3. The gas hot water supply apparatus according to claim 1, wherein the contents stored in said storage device when an abnormality occurs remain unchanged until a special input is made. A gas type hot water supply device characterized by being performed.