JPH1073315A - Hot water supply equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater which prevents the delivery of high temperature hot water when a water cock is accidentally opened by a user during the safely handing of abnormality in high temperature delivery of hot water or in the detection of residual flame. SOLUTION: A water heater 1 is constituted of a heat exchanger 2, an incoming water channel 6 and a hot water delivery path 8 connected to the heat exchanger 2, a bypass path 10 for making the incoming water channel 6 communicate with the hot water delivery path 8 bypassing the heat exchanger 2, a flow rate adjusting valve 12 which is provided on the bypass path 10 to adjust the bypass flow rate and a boiler side control valve 22 provided on the hot water delivery path. In this case, an abnormality detection means is provided to detect the abnormality of the water heater 1 and a safe handling means to fully close a flow rate adjusting valve 12 and a boiler side control valve 22 when the abnormality detection means detects the abnormality in the high temperature delivery of hot water (or the abnormality in the detection of residual flame).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply apparatus, and more particularly, to a hot water supply apparatus that prevents high-temperature hot water supply during safe operation.

[0002]

2. Description of the Related Art Conventionally, as this type of hot water supply apparatus, a water inlet and a water outlet are respectively connected to a heater, a can body side control valve is provided on a water outlet side, and a water inlet and a water outlet are connected. There is a configuration in which a short circuit occurs between the bypass paths, and a flow control valve is provided in the bypass path. Then, at the time of tapping, the gas burner is ignited and water is passed to the heating side together with the bypass,
The hot water heated by the heater and the water flowing through the bypass are mixed, and desired hot water is discharged.

When an abnormality occurs in such a hot water supply apparatus, combustion is stopped and the control valve on the can body side and the flow control valve on the bypass passage are fully opened or set to a predetermined initial position. I have. This is because a large amount of water is allowed to flow when the faucet is opened even at the time of abnormal stop, so that low-temperature hot water can be supplied.

[0004]

Although such a hot water supply device has been conventionally used, the following problems may occur. When the hot water supply abnormality was detected during the hot water supply operation and the hot water supply operation was stopped by the safety operation, high temperature hot water was in the hot water path leading to the faucet, and the valve was opened as in the past. When the faucet is opened, high-temperature hot water remaining in the hot water supply channel is first discharged, and then loose hot water is supplied, and the user inadvertently opens the faucet despite safe operation. If this happens, hot water will come out.

In a hot water supply device, a water flow switch is stuck at an ON position and becomes difficult to move. In a device using a flow rate sensor, noise similar to a pulse signal from a flow rate sensor may flow into a control device. Or the microcomputer (CPU) in the control unit runs out of control, causing the unit to mistakenly recognize that there is a flow rate higher than the minimum operating flow rate (MOQ) and burn even though there is no actual water flow. (This is called embers.)

[0006] Even when the safe operation is performed due to embers, high temperature hot water enters the hot water path leading to the faucet, and there is the same problem as in the case described above.

Accordingly, the present invention has been made in view of the above-described problems, and a high-temperature hot water tap is provided even when a user inadvertently opens a faucet despite safe operation. It is an object of the present invention to provide a hot water supply device that prevents such a problem.

[0008]

In order to achieve the above object, the invention according to claim 1 provides a heat exchanger, a water inlet and a water outlet connected to the heat exchanger, and a bypass for the heat exchanger. A bypass path that communicates the water inlet path and the hot water path, and a flow control valve that is provided in the bypass path and adjusts a bypass flow rate;
In a water heater having a can body side control valve provided in the hot water supply path, an abnormality detecting means for detecting an abnormality of the water heater, and when the abnormality detecting means detects a high temperature hot water abnormality (or a residual fire detection abnormality), And a safety processing means for fully closing the flow control valve and the can body side control valve.

According to the first aspect of the invention, when a high-temperature hot water supply abnormality (or a residual combustion is detected), the control valve on the can body side and the flow control valve on the bypass passage are completely closed. Even when the tap is opened, hot water of high temperature is not discharged and it is safe.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS. 1 and 2 are schematic configuration diagrams of the hot water supply device of the present invention, and FIG. 3 is a flowchart for explaining the operation.

In the illustrated hot water supply apparatus 1, reference numeral 2 denotes a heat exchanger, reference numeral 3 denotes a combustion detection sensor, reference numeral 4 denotes a heater such as a gas burner for heating the heat exchanger 2, and reference numeral 6 denotes an inlet connected to a water pipe (not shown). A water channel 8 is a hot water channel that communicates with a terminal plug 5 such as a kitchen, a lavatory, or a shower, and 10 is a bypass channel for bypassing the heat exchanger 2 between the water inlet channel 6 and the hot water channel 8.
Is a flow control valve provided in the bypass passage 10 to adjust the amount of bypass water, and 14 is a valve body of the flow control valve 12 (not shown).
, A stepping motor for driving the
Flow rate sensor for detecting the flow rate flowing through
c, an inlet water temperature sensor for detecting the outlet temperature Th of the hot water heated by the heat exchanger 2;
0 is a hot water supply temperature sensor that detects the hot water supply temperature Tm after the hot water heated in the heat exchanger 2 and the water that has passed through the bypass 10 are mixed, and 21 detects the amount Qh of water entering the heat exchanger 2. A water input sensor 22 is a can body side control valve for controlling the amount of hot water discharged when the amount of water flowing into the heat exchanger 2 exceeds the maximum heating capacity, and 23 is a proportional valve for adjusting the heating amount of the heater 4, 2.
Reference numeral 4 denotes a controller for controlling the above-mentioned components in relation to the hot water supply operation, and reference numeral 26 denotes an operation unit for setting a target hot water supply temperature Ts.

Next, the controller 24 will be described with reference to FIG. The controller 24 includes various sensors 1
Based on the detection information such as 5 and 16, the flow rate control valve 12, the can body side control valve 22, the proportional valve 23, and the like are controlled. In particular, hot water supply control means 30, abnormality detection means 31, safety processing means 32 , And other control means 33. The hot water supply control means 30 is a means for controlling each operation section at the time of a normal hot water supply operation, and recognizes the presence or absence of a hot water supply request based on the water supply amount Qh detected by the water supply amount sensor 21, and performs the following feedforward control during the hot water supply operation. And perform feedback control. The feedforward control is performed by setting the target temperature KTs in the heat exchanger 1 to a predetermined value β that is a required constant value β so that the target temperature KTs falls within an appropriate range outside the low-temperature corrosion zone or the boiling zone.
(For example, 25 ° C.), and the gas amount G of the heater 4 is set to (KT) such that the tapping temperature Th detected by the tapping temperature sensor 18 matches the target heating temperature KTs.
s−Tc) · QH and set the target distribution ratio BpFF to (KTs−Tc) / (Ts−T).
c) = β / (Ts−Tc), and a target number of steps (target value) SFF is calculated based on the relationship between the number of steps of the stepping motor 14 and the hot and cold water distribution ratio based on the target distribution ratio BpFF. It is. The feedback control calculates an actual water distribution ratio BpA based on the incoming water temperature Tc, the outlet water temperature Th from the heat exchanger 2, and the actual hot water supply temperature Tm after mixing the hot and cold water, and calculates the actual distribution ratio BpA. A deviation amount ΔBp (= BpA−BpFF) between the target distribution ratio BpFF and the target distribution ratio BpFF is obtained for each predetermined sampling period Δt, and a corrected distribution ratio BpFB is calculated based on the deviation amount ΔBp. The feedforward control, the feedback control, or the feedforward + feedback control is appropriately used in the control state to perform optimal control.

The abnormality detecting means 31 determines whether an abnormality has occurred,
This is a means for detecting the contents.

The safety processing means 32 is a means for processing a safety operation when an abnormality occurs. In particular, the safety processing means 32 is designed to prevent hot water from flowing out when the user does not intend. Other control means 3
Reference numeral 3 denotes a unit that performs control operations other than those described above, and controls detection operations of various sensors 15 and 16 and controls transmission of data with the operation unit 26.

Next, the safety operation of the present invention will be described with reference to the flowchart of FIG. First, the abnormality detecting means 31 detects the presence or absence of an abnormality, and the safety processing means 32 determines whether or not a safe operation is necessary (step S1). As a judgment, when combustion is not detected despite performing the combustion operation, when an afterburning abnormality is detected, or when a hot water supply operation is performed, a high-temperature hot water is higher than a set temperature, or This is a case where various abnormal operations are performed, for example, when a low-temperature hot water that is lower than the set temperature is obtained. In step S1, if there is no need for the safety operation, the normal control operation is continued (step S2).

If a safe operation is required in step S1, it is next determined whether or not the cause of the abnormality is a safe operation due to a high-temperature hot water supply abnormality in which hot water having a temperature higher than a desired temperature is supplied (step S3). If the high-temperature hot water supply is not abnormal, the can body control valve 22 and the flow control valve 12 in the bypass are fully opened (or the initial position is reset) (step S4). If the hot water supply is abnormal, the can-side control valve 22 and the flow control valve 12 in the bypass passage are fully closed (step S5). Step S4
The opening operation of the valves 12 and 22 is performed as described above.
If the valves 2 and 22 are fully closed, it will not be possible to supply water that does not require combustion. Therefore, it is desirable to open the valve as much as possible. In this case, a large amount of water is made to flow at full opening or the like to make the water loose. On the other hand, in the case of a high-temperature hot water supply abnormality, since the hot water is filled in the hot water path 8 up to the terminal plug 5 even after the hot water supply operation is once stopped, the user inadvertently opens the terminal plug 5. Also, it is easier for the user to prevent hot water from being discharged. If both the flow control valve 12 and the can body side control valve 22 of the bypass are completely closed at this time, even if the terminal plug 5 is otherwise opened, the upstream side is completely sealed. The hot water in the hot water path 8 does not flow out of the hot water. Even if a small amount of hot water leaks out, there is no need to worry because the amount is small. Further, the present invention can be realized without the necessity of separately providing an electromagnetic valve for opening and closing near the terminal plug 5.

Next, another embodiment will be described. In the above-described embodiment, the can body side control valve 22 and the flow rate regulating valve 12 of the bypass passage are fully closed at the time of the safe operation by the detection of the high-temperature hot water supply. As in step S5 in FIG. 2, both the can body-side control valve 22 and the flow control valve 12 in the bypass passage are fully closed. If there is an embers, the embers will further heat the hot water in the tapping water channel 8 to a higher temperature. At this time, even if the user inadvertently opens the terminal plug 5, hot water having a temperature higher than the desired temperature is not discharged. Here, the abnormal detection of the residual fire can be performed, for example, by the combustion detection sensor 3 detecting the combustion even though the combustion command is not issued from the controller 24.

[0018]

As described above, according to the present invention, when a high-temperature hot water supply abnormality or a residual fire is detected, the can body side control valve 2 is controlled.
2 and the flow control valve 12 of the bypass passage are completely closed, so that even if the terminal plug 5 is opened, hot water having a temperature higher than the temperature desired by the user is not discharged, so that there is an effect that it is safe. In addition, since it is open during a safe operation other than in such a case, it is easy to use and convenient because hot water can be supplied.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a configuration of a hot water supply device.

FIG. 2 is an explanatory diagram of a controller.

FIG. 3 is a flowchart showing the operation of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 hot water supply device 2 heat exchanger 3 combustion detection sensor (residual fire detection means) 4 heater 6 water inlet channel 8 hot water outlet 10 bypass channel 12 flow control valve 22 can body side control valve 24 controller 26 operation unit 30 hot water supply control unit 31 abnormality detection Means 32 Safety processing means

Continued on the front page (72) Inventor Eiichi Tsuji No. 93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Pref.

Claims (1)

[Claims] 1. A heat exchanger, a water inlet and a hot water outlet connected to the heat exchanger, a bypass for bypassing the heat exchanger and connecting the water inlet and the hot water outlet, and a bypass provided in the bypass. In a water heater having a flow rate adjusting valve for adjusting a flow rate and a can body side control valve provided in the tapping path, an abnormality detecting means for detecting an abnormality of the water heater, and the abnormality detecting means includes a high temperature hot water abnormality (or a residual hot water). And a safety processing means for completely closing the flow control valve and the can body side control valve when detecting fire detection abnormality).