JP6177053B2 - Water heater - Google Patents

Description

  The present invention relates to a hot water supply device having a freeze prevention function.

  There is a hot water supply device having a function of preventing freezing of water in a pipe. For example, in a hand-washing device that instantaneously heats the water supply with a heater and discharges water for hand-washing, when the temperature of the water supply is monitored and it is determined that the inside of the water passage is frozen, heating by the heater and discharge operation of the water supply are performed. There is one that is automatically performed (see Patent Document 1).

  Further, in Patent Document 2, when a nuclear power plant is constructed, if water is passed in a cold district for winter in order to clean pipes or perform an operation test, the device may freeze at night and damage the equipment. A construction management method is disclosed in which water is retained in a freezing place and freezing prevention is performed by a heater.

JP 2013-7164 A JP 2011-215192 A

  In cold regions, when equipment such as a water heater is stored in a warehouse, the equipment may be sufficiently cooled down. When such a cooled device is installed on the site and water is passed, there is a problem that the temperature of the water decreases while flowing in the pipe and freezes in the middle. In particular, it freezes in the vicinity of a forged part (for example, a solenoid valve) having a large negative heat storage amount.

  The techniques disclosed in Patent Documents 1 and 2 prevent freezing during a water flow stop after water has passed through a pipe, and cannot cope with the above problem.

  The present invention is intended to solve the above-described problem, and in the first water flow after installation in winter, a hot water supply device that can prevent a problem that water freezes in the middle of flowing through a pipe. It is intended to provide.

  The gist of the present invention for achieving the object lies in the inventions of the following items.

[1] Piping for flowing water flowing from the water supply port to each part of the aircraft;
Opening and closing the water supply opening, and an opening and closing unit that is closed in the initial state when the device is installed,
A heater provided in the pipe;
At the time of the first energization after installation, the controller that opens the opening and closing unit after heating the pipe with the heater,
A hot water supply apparatus characterized by comprising:

  In the above invention, even when a hot water supply device is installed in the cold winter, the opening and closing part is closed in the initial state of installation, so even if water supply reaches the water supply port from the water supply pipe, It does not flow into the piping inside the device and freeze in the middle of the piping. Also, at the first energization after installation, the opening and closing part is opened after heating the pipe with the heater, so the opening and closing part opens with the water supply stopped at the opening and closing part frozen, and the valve body is damaged. It is prevented that the water supplied from the water supply port freezes in the middle of the pipe.

[2] The control unit maintains the open / close unit in a closed state until a predetermined time elapses after the first energization start after installation, and heats the pipe with the heater during the period. The hot water supply apparatus according to 1].

  In the above invention, at the time of the first energization after installation, the heater is turned on uniformly with the opening / closing portion closed until a predetermined time elapses from the start of energization. The time for which the heater is turned on is easier to control and does not require a dedicated temperature sensor, for example, as compared with the case where the temperature of the opening / closing section is detected and controlled.

[3] The control unit performs on / off control of the heater based on a temperature detected by a temperature sensor in order to prevent freezing in the pipe in a normal state where water is contained in the pipe.
The heater is used so that it does not overheat even if it is turned on when there is no water in the piping and does not break down, and can obtain a heat generation amount that can prevent freezing when there is water in the piping. The hot water supply apparatus according to [1] or [2].

  In the above invention, the heater is used not only to prevent freezing in the first water flow after installation, but also to prevent freezing in the pipe in a normal state where water is contained in the pipe. That is, the heater is used both when the pipe has water and when there is no water. For this reason, a pipe that does not break down due to overheating is used even when it is turned on in a state where there is no water in the pipe (a state where the amount of heat radiation is small).

[4] The hot water supply device according to any one of [1] to [3], wherein the opening / closing portion is an electromagnetic valve that opens when turned on and closes when turned off.

  In the above-described invention, if a solenoid valve that is closed when energization is used for the opening / closing part, a closed state is naturally formed in the initial state after installation.

[5] The hot water supply apparatus according to [3], wherein the opening / closing unit includes a gear motor and is opened and closed by the gear motor.

  In the above invention, the gear motor of the opening / closing part is set to a position where the valve is closed at the time of factory shipment. When the power is turned off after the first energization, the opening / closing valve can be opened.

[6] A temperature sensor for detecting the temperature of the water supply port is provided,
The control unit maintains the open / close unit in a closed state until the temperature detected by the temperature sensor reaches a predetermined temperature from the first energization start after installation, and the pipe is heated by the heater during that time. The hot water supply apparatus according to [1].

  In the said invention, it can be judged from the temperature of a water supply port whether the water supply is frozen in the part of a water supply port.

  According to the hot water supply apparatus according to the present invention, in the first water flow after installation in winter, it is possible to prevent a problem that water freezes in the middle of flowing through the pipe.

It is a figure which shows schematic structure of the hot water supply apparatus which concerns on embodiment of this invention. It is a flowchart which shows the process at the time of power-on of the hot water supply apparatus which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration of a hot water storage system 3 using a hot water supply apparatus 10 according to an embodiment of the present invention. The hot water storage system 3 includes a hot water supply device 10, a heat source device 4 that recovers exhaust heat of the fuel cell, and a backup heat source device 5.

  The hot water supply device 10 stores the water supplied from the water supply source through the water supply pipe 6 in the hot water storage tank 11, raises the temperature of the water in the hot water storage tank 11 using the exhaust heat of the fuel cell, and supplies a predetermined hot water outlet. Serves the function of supplying hot water. The backup heat source unit 5 functions to elevate the temperature of the hot water to the set temperature on the way from the hot water storage tank 11 to the hot water destination when the temperature of the hot water sent from the hot water storage tank 11 is insufficient for the set temperature of the hot water.

  Here, a bath water heater that burns gas is used as the backup heat source unit 5. Hot water from the hot water supply device 10 is supplied to the water supply port of the bath water heater 5.

  When the temperature of the hot water delivered from the hot water storage tank 11 exceeds the set temperature of the hot water, the hot water supply device 10 mixes the hot water from the hot water storage tank 11 with the hot water and adjusts the temperature to the set temperature. The bath water heater 5 supplies the supplied hot water to the hot water outlet as it is. On the other hand, when the temperature of the hot water sent out from the hot water storage tank 11 is less than the set temperature of the hot water, the bath water heater 5 burns the burner and raises the hot water supplied from the hot water supply device 10 to the set temperature. Take out the hot water at the hot spring.

  A hot water storage tank 11 provided in the hot water supply apparatus 10 is a hollow, substantially cylindrical, vertically long tank, and is replenished with water from the bottom and pumps hot water from the top. The hot water storage tank 11 has, for example, a capacity of about 100 liters, and is provided with a temperature sensor that detects the water temperature at the water level at every 20 liters from the bottom.

  A water supply pipe 6 leading to a water supply source is connected to the water supply pipe connection port 12 of the hot water supply apparatus 10. Inside the hot water supply device 10, water supplied from the water supply pipe connection port 12 is sent to the hot water storage tank 11, and the water taken out from the bottom of the hot water storage tank 11 is heated via the heat source unit 4 to increase the temperature of the hot water storage tank 11. Various pipes 13 are provided for returning to the upper part, mixing the hot water from the upper part of the hot water storage tank 11 or the hot water and the feed water, and sending them to the backup heat source unit 5 or draining them.

  In the middle of the pipe 13, a mixer, a solenoid valve, a check valve, a pressure reducing valve, a pump, a water amount sensor, and the like are provided. Further, a heater 14 for preventing freezing of water in the pipe 13 and a temperature sensor 15 for detecting the water temperature in the pipe 13 are attached to various places of the pipe 13. Moreover, the hot water supply apparatus 10 includes an ambient temperature sensor 16 that measures an ambient temperature (outside temperature).

  A water supply opening / closing valve 18 is provided in the pipe 13 in the vicinity of the water supply connection port 12. The water supply opening / closing valve 18 functions to substantially open and close the water supply pipe connection port 12. When the water supply opening / closing valve 18 is closed, the inflow of water from the water supply pipe connection port 12 is blocked. When the water supply opening / closing valve 18 is opened, water is supplied from the water supply pipe connection opening 12 to the hot water supply device 10. Inflow becomes possible.

  Generally, in a water heater or the like, water can be passed when the apparatus is in an initial state when installed or when the apparatus is turned off. However, the water supply opening / closing valve 18 of the hot water supply apparatus 10 of the present embodiment is closed in the initial state (before energization) when the hot water supply apparatus 10 is installed. For example, when the water supply opening / closing valve 18 is an electromagnetic valve, a configuration in which the valve closes in a power-off state is used. If the water supply opening / closing valve 18 is a gear motor that opens and closes the valve, the valve is set in a closed state and shipped from the factory. Thereby, in the initial state at the time of installation, the water supply opening / closing valve 18 is closed.

  The hot water supply apparatus 10 includes a circuit board 20 that functions as a control unit that controls the operation of the hot water supply apparatus 10. The circuit board 20 has a CPU (Central Processing Unit) on the board, a flash ROM (Read Only Memory) in which programs executed by the CPU and fixed data are stored, and various types of information are temporarily stored when the CPU executes the programs. RAM (Random Access Memory), I / F (Interface) section for inputting / outputting various signals, resistors, capacitors, and other components are arranged. Detection signals from various sensors included in the hot water supply apparatus 10 are input to the circuit board 20. Further, a control signal is output from the circuit board 20 to each valve and other control objects. The circuit board 20 further exchanges various information and commands with the heat source unit 4 and the backup heat source unit 5.

  Next, the freeze prevention operation of the hot water supply apparatus 10 will be described.

  In a normal state where water is contained in the pipe 13, the water heater 10 determines whether or not the water in the pipe 13 may freeze from the outside air temperature detected by the ambient temperature sensor 16. On / off of the heater 14 is always controlled so as not to freeze.

  On the other hand, when the power is turned on for the first time after installation, the hot water supply device 10 controls the heater 13 so that the pipe 13 and the water supply opening / closing valve 18 are sufficiently heated and then the water supply opening / closing valve 18 is opened.

  For example, at the first energization after installation, the water supply opening / closing valve 18 is maintained in a closed state until a predetermined time has elapsed from the start of energization, and the heater 13 is turned on during that time to connect the pipe 13 and the water supply opening / closing valve 18. Heat.

  In the winter season in cold regions, the hot water supply device 10 that has been stored in a cold warehouse for a long time may be cooled down before installation. When the hot water supply device 10 is installed and the water supply pipe 6 is connected to the water supply opening / closing valve 18 to supply water, the water supply opening / closing valve 18 is closed in the initial state. To reach the valve body and stop.

  The water supplied to the water supply opening / closing valve 18 is frozen immediately after the cold water supply opening / closing valve 18 is deprived of heat. For example, since the water supply opening / closing valve 18 is a forged part and has a large heat capacity, if it is cooled, it takes a lot of heat from the water supply and freezes the water supply.

  In general, the equipment is energized after the construction of gas pipes and water system piping is completed. This is because even if the amount is small, gas leaks during gas construction, and if an electric spark is added to this, the safety of the worker cannot be guaranteed. Similarly, hands may be wet with water during construction of the water system, and there is a risk of electric shock if the appliance is energized. That is, it is an ironic rule not to energize until the construction is completed at the time of equipment installation or repair. When AC100V is energized to the appliance after the construction is completed, the water supply opening / closing valve 18 attempts to open by energization. Then, the valve body of the water supply opening / closing valve 18 may be damaged or broken. However, in the hot water supply apparatus 10 according to the present embodiment, the heater 14 is turned on while the water supply opening / closing valve 18 is kept closed until a predetermined time elapses after the first energization start after installation. As a result, the temperature of the pipe 13 and the water supply opening / closing valve 18 rises, and the water supply frozen at the valve body of the water supply opening / closing valve 18 is melted.

  Therefore, even if the water supply opening / closing valve 18 is subsequently opened, the valve body of the water supply opening / closing valve 18 is not damaged or broken. Even if the water supply flows into the pipe 13 of the hot water supply device 10, the pipe 13 is already warmed by the heater 14, so that the water supply does not freeze in the pipe 13. In this way, a state in which the heater 14 is preheated until the water that has been frozen at the valve body of the water supply opening / closing valve 18 melts and the water supply does not freeze even if it flows into the pipe 13 of the hot water supply device 10 is defined as a preheat completion state. .

  The length of the predetermined time for turning on the heater 14 while maintaining the water supply opening / closing valve 18 closed after the first energization start after the installation is, for example, when the heater 14 is turned on at the lowest expected temperature. The time required until the preheating completion state is set to a time obtained by adding a predetermined margin.

  The heater 14 is used not only for heating to prevent freezing in the first water flow after installation, but also for heating to prevent freezing in the pipe 13 in a normal state where water is contained in the pipe 13. Is done. That is, the heater 14 is used both when there is water in the pipe 13 and when there is no water. Therefore, the heater 14 has a heat generation amount that does not overheat and fail even when energized (air-fired) in the pipe 13 without water, and that can prevent freezing in the presence of water in the pipe 13. What is obtained is used.

  For example, the resistance value of each heater is determined so that it will not overheat and fail even if energized in the absence of water, and the number of heaters is increased or decreased to ensure the necessary amount of heat generation.

  Moreover, it is preferable to attach the heater 14 to the water supply opening / closing valve 18 or its vicinity where the heat capacity is larger than that of the other pipes 13.

  FIG. 2 shows a flow of processing performed by the hot water supply apparatus 10 when the power is turned on. When the power supply is turned on, the hot water supply apparatus 10 checks whether or not the current power-on is the first power-on after installation (step S101). This determination is made with reference to the initial flag stored in the nonvolatile memory, for example. The initial flag is on, indicating that the power is on for the first time after installation. The initial state is turned on, and is reset in step S106 described later.

  If the power is turned on for the first time after installation (step S101; Yes), the anti-freezing heater 14 is turned on (step S102), and a timer for measuring a predetermined time is started (step S103).

  Until the timer expires (step S104; No), the heater 14 is kept on and the water supply opening / closing valve 18 is kept closed. Specifically, when an electromagnetic valve is used as the water supply opening / closing valve 18, the water supply opening / closing valve 18 is not energized until a predetermined time has elapsed since the first energization start after installation. Similarly, also when using a type that moves the valve element with a gear motor as the water supply opening / closing valve 18, the water supply opening / closing valve 18 is not energized until a predetermined time elapses after the first energization start after installation, or Do not move the gear motor.

  When the timer expires (step S104; Yes), the water supply opening / closing valve 18 is opened (step S105). Then, the initial flag is reset (step S106), and the normal operation is performed (step S107).

  In normal operation, the heater 14 is on / off controlled based on the temperature detected by the ambient temperature sensor 16 so that the water in the pipe 13 does not freeze.

  If the power is not turned on for the first time after installation (step S101; No), the process proceeds to step S107, and the process proceeds to normal operation (step S107).

  Thus, even when the hot water supply apparatus 10 according to the embodiment of the present invention is installed in a cold state, water is frozen in the middle of the pipe 13 inside the apparatus in the first water flow after installation. Can be prevented. Further, since the water supply opening / closing valve 18 is not forcibly moved in a frozen state, the valve body is not damaged.

  In addition, at the time of the first energization after installation, the heater 14 is turned on by keeping the water supply opening / closing valve 18 closed until a predetermined time elapses from the start of energization, so that the control is easy. . For example, as compared with the case where the time for turning on the heater 14 is controlled by detecting the temperature of the water supply opening / closing valve 18, the control is simple and a dedicated temperature sensor is not required.

  When a water supply opening / closing valve 18 of a type that opens and closes the valve element with a gear motor is used, it is desirable that the valve element be opened when the power is turned off after the initial energization after installation. For example, if a predetermined time elapses after the first energization after installation, it is possible to ensure water flow even in the event of a power failure if the state is always open.

  Further, the control for turning on the heater 14 by keeping the water supply opening / closing valve 18 closed until a predetermined time has elapsed from the start of energization is performed by examining the outside air temperature at the first energization after installation, If it is performed only when the temperature is lower than a predetermined threshold temperature, there is a possibility that the outside air temperature is higher than the threshold temperature, but the water supply opening / closing valve 18 formed by piping 13 or forging is still cold and freezes when water is passed through. . Therefore, in the present invention, the above control is uniformly performed at the first energization after installation.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration is not limited to that shown in the embodiment, and there are changes and additions within the scope of the present invention. Are also included in the present invention.

  In the embodiment, the heater 14 is turned on and the water supply opening / closing valve 18 is kept closed until a predetermined time has elapsed since the first energization after the installation, but for example, a portion of the water supply opening / closing valve 18 The temperature may be detected by a temperature sensor, and the heater 14 may be turned on and the water supply opening / closing valve 18 may be kept closed until the temperature reaches a predetermined temperature or higher. The predetermined temperature is set to a temperature obtained by adding a predetermined margin to the lowest temperature at which water is not frozen at the valve body.

  In the embodiment, the example in which the hot water supply device 10 forms a part of the hot water storage system 3 has been described. However, the present invention can be applied to other types of hot water supply devices 10 such as a water heater with a water amount adjusting valve and a bath water heater having a closing function. It can also be applied to.

  The heat source unit 4 of the hot water storage system 3 may not be a fuel cell. Moreover, although the backup heat source unit 5 is a bath water heater of a type that burns a burner, it is not limited to this.

3. Hot water storage system 4. Heat source machine (fuel cell)
5 ... Backup heat source machine (bath water heater)
DESCRIPTION OF SYMBOLS 6 ... Water supply pipe 10 ... Hot water supply apparatus 11 ... Hot water storage tank 12 ... Water supply pipe connection port 13 ... Piping 14 ... Heater 15 ... Temperature sensor 16 ... Ambient temperature sensor 18 ... Water supply port opening / closing valve 20 ... Circuit board

Claims (6)

Piping for flowing water flowing from the water supply port to each part of the aircraft,
Opening and closing the water supply opening, and an opening and closing unit that is closed in the initial state when the device is installed,
A heater provided in the pipe;
At the time of the first energization after installation, the controller that opens the opening and closing unit after heating the pipe with the heater,
A hot water supply apparatus characterized by comprising: The control unit maintains the open / close unit in a closed state until a predetermined time elapses after the first energization start after installation, and heats the pipe with the heater during the period. The hot water supply device described. The control unit performs on / off control of the heater based on a temperature detected by a temperature sensor to prevent freezing in the pipe in a normal state where water is contained in the pipe.
The heater is used so that it does not overheat even if it is turned on when there is no water in the piping and does not break down, and can obtain a heat generation amount that can prevent freezing when there is water in the piping. The hot-water supply apparatus of Claim 1 or 2 characterized by the above-mentioned. The hot water supply device according to any one of claims 1 to 3, wherein the opening / closing portion is an electromagnetic valve that opens when turned on and closes when turned off. The hot water supply apparatus according to claim 3, wherein the opening / closing part includes a gear motor, and is opened and closed by the gear motor. A temperature sensor for detecting the temperature of the water supply port;
The control unit maintains the open / close unit in a closed state until the temperature detected by the temperature sensor reaches a predetermined temperature from the first energization start after installation, and the pipe is heated by the heater during that time. The hot water supply apparatus according to claim 1.