JP4294624B2 - Hot water storage water heater - Google Patents

Description

  The present invention relates to a hot water storage type hot water supply apparatus that boils and stores hot water and uses the stored hot water for hot water supply.

  Conventionally, in this kind of thing, the applicant first supplies the water in the hot water storage tank to prevent freezing and corruption in the hot water storage tank when leaving for a long time on a business trip or travel. An application was filed by closing the stopper and opening the drain valve. (For example, see Patent Document 1)

However, in this conventional system, drainage is performed using a natural head, and the hot water storage tank capacity is 300L or more, and it takes more than 30 minutes to drain all, so you must wait until drainage is finished. It was necessary to drain the water in advance, which was troublesome and troublesome for the user.
Moreover, since it is drainage by a natural head, when the drainage channel is above, new construction is also required.

  Therefore, the applicant filed another application in which a drain pipe provided with a drain pump connected to the hot water storage tank is separately provided when the hot water in the hot water storage tank is drained. (For example, see Patent Document 2)

JP 2002-48405 A JP 2004-197957 A

  By the way, with this conventional one, there is a hot water supply mixing valve that mixes hot water from a hot water storage tank and water from a water supply pipe into hot water at a predetermined temperature so that the hot water boiled during operation is not mixed. Because the water side is fully open, there are places where water does not escape in the parts placed on the hot water side, such as hoppers, hot water mixing valves, intermediate mixing pipes, and hot water pipes, even after draining is complete. After the construction in winter, when it is not used for a long time, such as when it is not used for a period before delivery, business trip, travel, etc., the power is turned off, so the anti-freeze heater etc. is not energized to prevent freezing. The water that did not come off at the hopper, hot water supply mixing valve, intermediate mixing pipe, branch intermediate mixing pipe, and hot water outlet placed in the pipe may rupture and the functional parts such as the hopper and the mixing valve may be damaged. .

  Accordingly, in order to solve the above problems, the present invention provides a hot water storage tank for storing hot water, a water supply pipe for supplying water to the hot water storage tank, a water tap for opening and closing the water supply pipe, A hot water outlet pipe for discharging hot water from a hot water storage tank, a relief valve provided at the upper part of the hot water storage tank for releasing the overpressure in the hot water storage tank, hot water from the hot water discharge pipe and water from the water supply pipe are mixed and supplied to the hot water supply pipe. A hot water mixing valve, a drain pipe having one end connected to the bottom of the hot water storage tank, and a drain plug for opening and closing the drain pipe, and after closing the water tap and opening the relief valve, A drainage switch that opens the drain valve in the fully open state, then switches the hot water supply mixing valve to the hot water side fully open state, drains water, and then switches to the water side fully open state to perform the drainage mode. It is.

  Further, in the hot water storage type hot water supply apparatus according to claim 2, in particular, the configuration thereof includes a hot water storage tank for storing hot water, a water supply pipe for supplying water to the hot water storage tank, a water tap for opening and closing the water supply pipe, A hot water outlet pipe for discharging hot water from the hot water storage tank, a relief valve provided at the upper part of the hot water storage tank for releasing the overpressure in the hot water storage tank, an intermediate discharge pipe having one end connected to an intermediate portion of the hot water storage tank, and hot water from the hot water supply pipe Mixing hot water from the intermediate hot water pipe and the intermediate hot water from the intermediate hot water pipe and hot water from the intermediate hot water pipe and hot water supplied from the water supply pipe through the water supply bypass pipe The hot water mixing valve is provided with a hot water mixing valve that is connected to the bottom of the hot water storage tank, and a drain plug that opens and closes the drain pipe, and the hot water mixing valve is closed and the relief valve is opened. Open the drain valve with the water side fully open. And performs then drained by switching the hot water supply mixing valve of the state of the hot water side fully open, is subsequently hot-water supply mixing valve that is provided with drainage switch for draining mode to return to the state of the water side fully open.

  Further, in the hot water storage type hot water supply apparatus according to claim 3, in particular, in the structure of claim 1 and 2, a drainage timer for measuring a predetermined time is provided, and the drainage switch closes the water tap when performing the drainage mode. After opening the relief valve, open the drain valve with the hot water mixing valve fully open and start counting the drain timer. When the drain timer reaches the specified time, turn the hot water mixing valve to the hot water side. The drainage mode is performed by switching to the fully open state and draining and restarting the drainage timer, and when the drainage timer reaches a predetermined time, the hot water mixing valve is returned to the water side fully open state.

  Further, in the hot water storage type hot water supply apparatus according to claim 4, in particular, in the structure of claim 1 and 2, a water flow sensor is provided in the drain pipe, and when the drain switch performs the drain mode, the water tap is closed and released. After opening the valve, open the drain valve with the hot water mixing valve fully open and detect the drainage of the drain pipe with the flow sensor, and mix the hot water when the drain sensor no longer detects drainage of the drain pipe When the valve is switched to the hot water side fully open, drainage is performed, and then the drainage of the drain pipe is detected by the running water sensor, and when the running water sensor no longer detects drainage of the drain pipe, the hot water supply mixing valve is fully opened. The drainage mode to return to is performed.

  According to the first aspect of the present invention, after closing the water tap and opening the relief valve, the hot water mixing valve is opened with the water side fully open, the drain plug is opened, and then the hot water mixing valve is fully opened. A drainage switch that performs drainage mode to switch to drainage is provided, so the water side and hot water side pipes connected to the hot water storage tank and hot water mixing valve can be completely drained, so it is winter when not used for a long time Even if it becomes, freezing does not generate | occur | produce and it can prevent the failure | damage by piping rupture or freezing of a functional component.

  According to the hot water storage type hot water supply apparatus according to claim 2 of the present invention, the water tap is closed and the relief valve is opened, and then the hot water mixing valve is opened with the water side fully open to open the drain plug. Drain the water side of the water supply pipe to the hot water supply mixing valve and the water supply bypass pipe, then switch the hot water supply mixing valve to the hot water side fully open state, and the hot water side from the hot water supply pipe to the hot water supply mixing valve through the intermediate mixing pipe A drainage switch that performs a drainage mode is provided so that the water supply pipe from the drain tap to the hot water supply mixing valve, the water side water side of the water supply bypass pipe, and the hot water supply mixing valve from the hot water supply pipe through the intermediate mixing pipe Since the hot water side pipe can be completely drained, freezing does not occur even in the winter when it is not used for a long time, and it is possible to prevent damage caused by pipe rupture or freezing of functional parts.

  According to a third aspect of the present invention, in the hot water storage type hot water supply apparatus according to the first and second aspects, when the drainage timer is provided and the drainage timer counts a predetermined time, the hot water mixing valve is turned on. Since the hot water side fully open state or the hot water side fully open state is switched to the water side fully open state, the water side and hot water side pipes connected to the hot water storage tank and hot water mixing valve can be completely drained. When not used for a long period of time, freezing does not occur even in the winter, and it is possible to prevent damage due to piping rupture or freezing of functional parts.

  According to claim 4 of the present invention, in the hot water storage type hot water supply apparatus according to claim 1 or 2, the water flow sensor is provided in the drain pipe, and the water sensor detects the presence or absence of drainage in the drain pipe. By switching the hot water mixing valve from the water side fully open state to the hot water side fully open state, or from the hot water side fully open state to the water side fully open state, the water side and hot water side connected to the hot water storage tank and hot water mixing valve Since the inside of the pipe can be completely drained, freezing does not occur even in the winter when the pipe is not used for a long period of time, and it is possible to prevent damage caused by pipe rupture or freezing of functional parts.

Next, an embodiment of the present invention will be described with reference to the drawings.
This hot water storage type hot water supply device is used to boil hot water and store hot water in the midnight hours when the unit price of contracted electricity by time zone is low, and to use this hot water for hot water supply. In addition, indirect heat with hot water in the hot water storage can It is equipped with a hot water tank 2 for storing hot water, with a bath circuit for replenishing or keeping warm water in the bathtub and replacing the hot water in the hot water storage can directly into the bathtub. A hot water storage tank unit, 3 is a heat pump unit as a heating means for heating the hot water in the hot water storage tank 2, 4 is a hot water tap provided in a kitchen or a washroom, and 5 is a hot water remote controller provided near the hot water tap 4 , 6 is a bathtub, and 7 is a bath remote control provided in the bathroom.

  The hot water storage tank 2 of the hot water storage tank unit 1 has a hot water discharge pipe 8 connected to the upper end, a water supply pipe 9 connected to the lower end, a heat pump forward pipe 10 constituting a heat pump circulation circuit in the lower part, and a heat pump circulation circuit in the upper part. The heat pump return pipe 11 is connected, the hot water in the hot water storage tank 2 taken out from the heat pump forward pipe 10 is boiled by the heat pump unit 3 and returned to the hot water storage tank 2 from the heat pump return pipe 11 to be stored in the hot water supply pipe. The hot water in the hot water storage tank 2 is pushed up by the supply of water from the hot water 9, and the hot water in the upper part of the hot water storage tank 2 is pushed out from the hot water discharge pipe 8 to supply hot water.

The heat pump unit 3 includes a compressor 12, a refrigerant-water heat exchanger 13 as a condenser, an electronic expansion valve 14 as a decompressor, and a forced air-cooled evaporator 15, and a hot water storage tank 2. A heat pump circulation pump 17 that circulates the hot water in the refrigerant to the refrigerant-water heat exchanger 13 via the heat pump forward pipe 10 and the heat pump return pipe 11, and a heat pump control unit 18 that controls the drive of the heat pump. In the circuit 16, carbon dioxide is used as a refrigerant to constitute a supercritical heat pump cycle.
Since carbon dioxide is used as the refrigerant, low-temperature water can be boiled up to a high temperature of about 90 ° C. without an electric heater.

  Here, the refrigerant-water heat exchanger 13 employs a counter flow system in which the refrigerant and hot water in the hot water storage tank 2 that is heated water face each other. In the supercritical heat pump cycle, the refrigerant is used during heat exchange. Is condensed in a supercritical state, so that the water to be heated can be efficiently heated to a high temperature, and the temperature difference between the refrigerant-water heat exchanger 13 inlet temperature and the refrigerant outlet temperature becomes constant. By controlling the electronic expansion valve 14 or the compressor 12 as described above, when the inlet temperature of the refrigerant-water heat exchanger 13 to be heated is a low temperature of about 5 to 20 ° C., COP (energy consumption efficiency) However, it is possible to heat the water to be heated in a very good state.

Reference numeral 19 denotes a bath heat exchanger made of a stainless steel tube for heating the hot water in the bathtub 6, which is provided in an almost middle portion of the hot water storage tank 2. A bath return pipe 22 having a bath outlet pipe 20 and a bath circulation pump 21 is connected so that hot water in the bathtub 6 can be circulated, and the hot water in the bathtub 6 is heated by the high-temperature water in the hot water storage tank 2 to be kept warm. A chasing is done.
Reference numeral 23 denotes a bath temperature sensor for detecting the temperature of hot water in the bathtub 6 circulating through the bath return pipe 22.

  Reference numeral 24 is an intermediate take-out pipe connected at one end to the intermediate position facing the bath heat exchanger 19 on the side wall of the hot water storage tank 2, and the temperature is lowered by exchanging heat with the bath side in the bath heat exchanger 19. Hot water stored at an intermediate position of the hot water storage tank 2 such as warm water or intermediate temperature water whose temperature has decreased or increased in the vicinity of the boundary layer of hot water and water is discharged from the hot water storage tank 2.

  Reference numeral 25 denotes an intermediate mixing valve composed of an electric mixing valve for mixing high temperature water from the hot water discharge pipe 8 and intermediate temperature water from the intermediate discharge pipe 24, and 26 is provided in an intermediate hot water supply pipe 27 downstream of the intermediate mixing valve 25. With the intermediate temperature sensor, the hot water near the intermediate position of the hot water tank 2 and the hot water from the hot water pipe 8 connected to the upper end of the hot water tank 2 are set at a predetermined temperature from the hot water set temperature set by the user with the hot water remote controller 5 or the bath remote controller 7. The mixing ratio is controlled to achieve a high mixing target temperature.

  28 is a hot water mixing valve composed of an electric mixing valve that mixes hot water from the intermediate mixing valve 25 and low temperature water from the water supply bypass pipe 29 branched from the water supply pipe 9, and is provided in the hot water supply pipe 30 downstream thereof. The mixing ratio is controlled so that the hot water temperature detected by the hot water supply temperature sensor 31 becomes the hot water supply set temperature set by the user using the hot water remote controller 5 or the bath remote controller 7.

  32 is a bath mixing valve composed of an electric mixing valve that mixes hot water from the branched intermediate hot water pipe 33 branched from the intermediate hot water pipe 27 and low temperature water from the branched water supply bypass pipe 34 branched from the water supply pipe 9. The hot water temperature detected by the hot water temperature sensor 36 provided in the hot water pipe 35 knitted to the bath return pipe 22 on the downstream side becomes the bath set temperature set by the user with the hot water remote controller 5 or the bath remote controller 7. Thus, the mixing ratio is controlled.

  The hot water filling pipe 35 is provided with a hot water filling valve 37 for starting and stopping hot water filling to the bathtub 6 and a bath flow rate counter 38 for counting the amount of hot water filling to the bathtub 6. .

  A plurality of hot water storage temperature sensors 39 are arranged in the vertical direction of the hot water storage tank 2. In this embodiment, five temperature sensors 39 a, 39 b, 39 c, 39 d, 39 e are arranged, and temperature information detected by the hot water storage temperature sensor 39. Thus, the amount of heat remaining in the hot water storage tank 2 is detected, and the temperature distribution in the vertical direction in the hot water storage tank 2 is detected.

  The hot water remote controller 5 and the bath remote controller 7 are respectively provided with a hot water supply temperature setting switch 40 for setting a hot water supply set temperature and a bath temperature setting switch 41 for setting the bath set temperature, and a bath set temperature for the bathtub 6. The bath remote control 7 is provided with an automatic bath switch 42 that fills the hot water by a hot water filling amount set by a hot water filling amount setting switch (not shown) of the bath remote control 7 and keeps it warm for a predetermined time. A hot water hot water switch 43 for pouring hot water at a high temperature of 0 ° C. is provided.

Reference numeral 44 denotes a control unit having a microcomputer that receives the input of each sensor in the hot water storage tank unit 1 and controls the drive of each actuator.
The hot water remote controller 5 is connected to the controller 44 by radio or wire so that the user can set an arbitrary hot water set temperature and bath set temperature.

  The controller 44 feeds back the valve opening degree of the intermediate mixing valve 25 so that the temperature detected by the intermediate temperature sensor 26 becomes a mixing target temperature that is higher by a predetermined temperature than the higher set temperature of the hot water supply set temperature or the bath set temperature. The valve opening degree of the hot water supply mixing valve 28 is feedback controlled so that the temperature detected by the hot water supply temperature sensor 31 becomes the hot water supply set temperature. The valve opening degree of the bath mixing valve 32 is feedback-controlled so that the temperature detected by the sensor 36 becomes the bath set temperature.

  The controller 44 is set so that the control response speed of the intermediate mixing valve 25 is slower than the control response speed of the hot water supply mixing valve 28. The control response speed of the feedback control of the valve 28 is superior, and the overshoot or undershoot of the hot water supply temperature can be greatly reduced.

  45 is a relief valve for releasing the overpressure in the hot water storage tank 2, 46 is a pressure reducing valve for reducing the pressure of the water supply, 47 is a hot water flow rate counter for counting the amount of hot water to be supplied, and 48 is for the hot water in the bathtub 6 to flow backward. A check valve 49 provided to prevent this is a water supply temperature sensor that detects the temperature of the water supply.

Reference numeral 50 denotes a water tap that opens and closes the water supply pipe 9 and is provided upstream of the pressure reducing valve 46 provided in the water supply pipe 9.
A drain pipe 51 is connected at one end to the bottom of the hot water storage tank 2. The drain pipe 51 is provided with a drain plug 52 that opens and closes the drain pipe 51. A flowing water sensor 53 for detecting the presence or absence is provided.
A drain switch 54 is provided in the hot water remote controller 5 and executes a drain mode when pressed to drain the hot water storage tank 2 and piping.

Next, the drainage operation of the present invention will be described with reference to FIG.
First, when the drain switch 54 is turned on to start the drain mode (S1), the water tap 50 is closed (S2), and the relief valve 45 is opened. (S3)
Then, if the hot water supply mixing valve 28 is in the fully open state on the water side (S4), the drain plug 53 is opened (S5), and the water supply pipe 9 from the drain plug 53 to the hot water supply mixing valve 28 and the water in the water supply bypass pipe 29 If the hot water mixing valve 28 is not in the fully open state on the water side (S4), the hot water mixing valve 28 is switched to the fully open state on the water side (S6), and then the drain plug 53 is opened. (S5) Drainage of the water side of the water supply pipe 9 and the water supply bypass pipe 29 from the drain plug 53 to the hot water supply mixing valve 28 is started.
At the same time, the timing of a drainage timer (not shown) that counts the drainage time is started. (S7)

  Then, if the predetermined time that has been confirmed in advance, that is, the time when all hot water in the hot water storage tank 2 is drained and drained, for example, 10 minutes, is 10 minutes after the drain timer starts counting. (S8), the hot water supply mixing valve 28 is switched from the water side fully open state to the hot water side fully open state (S9), and the hot water side hot water supply mixing valve 28, the intermediate mixing pipe 27, and the outlet pipe 8 are discharged. At the same time, the timer of the drainage timer is started again. (S10)

  Then, if the predetermined time that has been confirmed in advance, that is, the time when all hot water remaining in the hot water side pipe is drained and the hot water side pipe is emptied, for example, 3 minutes, is set to 3 minutes. When 3 minutes have elapsed from the start (S11), it is determined that drainage has been completed, and the hot water supply mixing valve 28 is switched from the hot water side to the water side fully open state (S12), and the drainage mode is terminated ( S13).

  As another embodiment, instead of the drainage timer, a drainage water sensor 53 is provided in the drainage pipe 51, and when the drainage mode is performed, the running water sensor 53 detects the presence or absence of drainage to detect the empty in the hot water storage tank 2. This will be described with reference to FIG.

First, when the drain switch 54 is turned on to start the drain mode (S1), the water tap 50 is closed (S2), and the relief valve 45 is opened. (S3)
Then, if the hot water supply mixing valve 28 is in the fully open state on the water side (S4), the drain plug 53 is opened (S5), and the drainage of the water supply pipe 9 from the drain plug 53 to the hot water supply mixing valve 28 and the water supply bypass pipe 29 is performed. If the hot water mixing valve 28 is not in the water side fully open state (S4), the hot water mixing valve 28 is switched to the water side fully open state (S6), and then the drain plug 53 is opened (S5). Then, drainage of the water supply pipe 9 and the water supply bypass pipe 29 from the drain plug 53 to the hot water supply mixing valve 28 is started.

  Next, when the flowing water sensor 53 provided in the drain pipe 51 detects drainage in the drain pipe 51 (S14), it is determined that the hot water mixing valve 28 is drained in a state where the water side is fully opened, and the flowing water sensor 53 drains. When the drainage water in the pipe 51 is not detected, and after the running water sensor 53 detects the drainage in the drainage pipe 51 and the running water sensor 53 no longer detects the drainage in the drainage pipe 51 (S15), the hot water supply mixing valve 28 is turned on. It is determined that the drainage in the water side fully open state is completed, and the hot water supply mixing valve 28 is switched from the water side fully open state to the hot water side fully open state (S9), and the hot water side hot water supply mixing valve 28 and the intermediate mixing pipe 27 are switched. Then, drainage of the tapping pipe 8 is started.

  Then, when the running water sensor 53 detects drainage in the drain pipe 51 (S16), it is determined that the hot water mixing valve 28 is drained in a state where the hot water side is fully opened, and the running water sensor 53 drains the drainage in the drain pipe 51. If not detected, and after the flowing water sensor 53 detects drainage in the drainpipe 51, if the flowing water sensor 53 no longer detects drainage in the drainpipe 51 (S17), the hot water supply mixing valve 28 is in a state where the hot water side is fully open. Is determined to be completed, and the hot water mixing valve 28 is switched from the hot water side fully open state to the water side fully open state (S12), and the drain mode is terminated (S13).

  According to the present invention, in addition to the water-side pipe portion, the water in all pipes can be drained, including hot-water-side pipes such as the hot water supply mixing valve 28, the intermediate mixing pipe 27, the branch intermediate mixing pipe 33, and the hot water outlet pipe 8. Therefore, after winter construction, when it is not used for a long period of time, such as when it is left for delivery, business trips, travel, etc., it prevents the pipe from rupturing and damages to functional parts such as hoppers and mixing valves, and makes the equipment reliable. The number of maintenance can be reduced.

The schematic block diagram of one Embodiment of this invention. The flowchart figure which shows the drainage mode. The flowchart figure which shows the drainage mode of the other Example of this invention.

Explanation of symbols

2 Hot water storage tank 8 Hot water discharge pipe 9 Water supply pipe 28 Hot water supply mixing valve 45 Relief valve 51 Drain pipe 52 Drain plug 54 Drain switch

Claims (4)

A hot water storage tank for storing hot water, a water supply pipe for supplying water to the hot water storage tank, a water tap for opening and closing the water supply pipe, a hot water outlet for discharging hot water in the hot water storage tank from the hot water storage tank, and an upper part of the hot water storage tank. A relief valve that releases overpressure in the hot water storage tank, a hot water mixing valve that mixes hot water from the hot water discharge pipe and water from the water supply pipe, and supplies the hot water supply pipe to the hot water supply pipe, and a drain pipe that has one end connected to the bottom of the hot water storage tank And a drain plug that opens and closes the drain pipe. After closing the water tap and opening the relief valve, the water tap is opened with the hot water mixing valve fully open, and then the hot water mixing valve is heated. A hot water storage type hot water supply apparatus provided with a drainage switch for performing a drainage mode for switching to a fully open side and draining, and then returning a hot water mixing valve to a fully open side. A hot water storage tank for storing hot water, a water supply pipe for supplying water to the hot water storage tank, a water tap for opening and closing the water supply pipe, a hot water outlet for discharging hot water in the hot water storage tank from the hot water storage tank, and an upper part of the hot water storage tank. A relief valve that releases overpressure in the hot water storage tank, an intermediate take-out pipe with one end connected to the intermediate part of the hot water storage tank, hot water from the hot water pipe and hot water from the intermediate take-out pipe are mixed and supplied to the intermediate hot water pipe An intermediate mixing valve, a hot water mixing valve that mixes hot water from the intermediate hot water supply pipe and water supplied from the water supply pipe via the water supply bypass pipe, and one end is connected to the bottom of the hot water storage tank. A drain pipe and a drain plug for opening and closing the drain pipe. After the water tap is closed and the relief valve is opened, the hot water mixing valve is opened with the water side fully open, and then the hot water mixing is performed. Switch the valve to the hot water side fully open and drain Was carried out, then the hot water supply mixing valve hot water storage type water heater, characterized in that a drainage switch for draining mode to return to the state of the water side fully open. A drainage timer that keeps a predetermined time is provided, and when the drainage switch performs the drainage mode, after closing the faucet and opening the relief valve, the drainage tap is opened with the hot water mixing valve fully open on the water side and the drainage timer. When the time of the drainage timer reaches the predetermined time, the hot water mixing valve is switched to the hot water side fully open state to drain the water, and the time of the drainage timer is restarted. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein a drainage mode for returning the hot water supply mixing valve to the water side full open state is performed when the temperature reaches the value. A drainage sensor is installed in the drainage pipe, and when the drainage switch is in drainage mode, after closing the faucet and opening the relief valve, open the drainage tap with the hot water mixing valve fully open on the water side and When the drainage of the drainage pipe is detected and the running water sensor no longer detects drainage of the drainage pipe, the hot water mixing valve is switched to the fully open state on the hot water side, and the drainage of the drainage pipe is detected by the running water sensor. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein when the running water sensor stops detecting the drainage of the drain pipe, the drainage mode is performed to return the hot water mixing valve to the water side fully open state.

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