JP4986911B2 - Hot water storage water heater - Google Patents

Description

  The present invention relates to a hot water storage type water heater.

  When boiling hot water in a hot water storage tank in a hot water storage type water heater, the volume of water expands as the temperature of the water (hot water) rises. Therefore, in order to prevent an increase in the internal pressure of the hot water storage tank and the piping circuit connected thereto, it is necessary to discharge hot water corresponding to the expanded amount (hereinafter referred to as expanded water). In addition, as the hot water in the hot water tank is boiled, the air dissolved in the water cannot be dissolved, and a part of the air is in a gas state. If this gas remains in the hot water storage tank or piping circuit, it may cause corrosion, gas may be mixed with the hot water at the time of hot water, and hot water may be splashed at the hot water tap. It may cause inconveniences to users such as getting wet or unpleasant sounds. For this reason, it is necessary to discharge the expanded water and gas from the hot water storage tank and the piping circuit.

  Conventionally, a method has been used in which the expanded water and the generated gas are discharged by a pressure relief valve that opens when the internal pressure of the hot water storage tank increases. However, if a pressure relief valve is installed in the upper part of the hot water storage tank, the heated hot water will be discharged at the same time, resulting in a loss of hot water storage energy.

  As a hot water type hot water heater that discharges hot water as much as possible, in the hot water type hot water heater that supplies hot water through a pipe connected to a hot water storage tank that stores hot water heated by a heating source, An overpressure relief valve is connected via a mixing valve that mixes the hot water in the hot water and the low temperature water from the lower part of the hot water storage tank. Further, in this prior document, “a calculation means for calculating the hot water storage operation time to the hot water storage tank, and the mixing valve is controlled to an opening degree at which low temperature water from the lower portion of the hot water storage tank first flows as much as possible and hot water storage A control device is provided that controls the opening so that high-temperature water from the upper part of the hot water tank flows as much as possible before the operation time elapses (see, for example, Patent Document 1).

JP 2006-145047 A (page 3-6, FIG. 1)

  However, in the conventional invention, since the pressure relief valve is provided at the outlet of the faucet and the hot water supply side mixing valve connected to the faucet, the control of the mixing valve is performed in the case of a power failure when the mixing valve is in a high temperature water side opening degree. Cannot be done. For this reason, when the user opens the faucet in this state, there is a risk that high-temperature water will come out against the user's will. Even if a power outage does not occur, if the user discharges hot water from the faucet while the mixing valve is fixed at a large water side or high temperature water side to discharge the expanded water or gas, the water side or Since it is necessary to control the mixing valve so that the target hot water temperature is reached from a state where the hot water side is fully open, it takes a long time to reach the target mixing temperature.

  In the conventional invention, the mixing valve is switched from the water side to the high-temperature water side during boiling of the hot water tank, and the gas in the hot water storage circuit is discharged in the final boiling process, but the generation of gas is detected. This is not to say that gas will remain if control is inadequate. Also, if the mixing valve is switched from the water side to the high temperature water side earlier, more gas can be discharged, but at the same time, the amount of high temperature water discharged increases and the loss of hot water storage energy increases. End up.

  In addition, in a hot water storage water heater having two hot water mixing valves, that is, a general hot water supply side (hot water supply end: faucet) and a bath hot water supply side (hot water supply end: bathtub), the hot water tank reaches the mixing valve from the top. Two pipes exist. For example, there are configurations such as two branches on the way from the upper part of the hot water tank, or two systems are independently connected from the upper part of the hot water tank. In this case, even if a pressure relief valve is installed at the outlet of the hot water supply side mixing valve and the gas is discharged from the bath side circuit, the gas in the general hot water supply side piping is not discharged, so there is a disadvantage that it remains. It was.

  Further, in the configuration of the conventional invention, for example, the control method can be changed so that the opening degree of the mixing valve is set to an intermediate opening degree between the water side and the high temperature water side. In this case, water and gas can be discharged simultaneously during boiling of the hot water storage tank, and switching control from the water side to the high temperature water side of the mixing valve is not necessary. However, in the configuration of the conventional invention, since the check valve is not provided on the inlet side of the mixing valve connected to the pressure relief valve, the low-temperature water is bypassed the intermediate opening mixing valve during the boiling operation, Inflow into the water and mixing with high-temperature water may cause a disadvantage that the hot water storage temperature is lowered and the hot water storage energy is lost.

  The present invention has been made in order to solve the above-described problems, and provides a hot water storage type hot water heater that can appropriately discharge expanded water and gas and has little energy loss.

In the hot water storage type hot water heater according to the present invention, a hot water storage tank for storing hot water, a heat source unit for heating the water in the hot water storage tank and returning it to the hot water storage tank, and a lower part of the hot water storage tank , the hot water storage tank wherein the water supply pipe for supplying water, which is connected to the upper portion of the hot water storage tank, the storage-type water heater and a hot water pipe for tapping the pooled high temperature water in the hot water storage tank, provided in the tapping tube, and low-temperature water to a hot water supply mixing valve for mixing the hot water from the hot water storage tank, prior SL and a valve relief pressure, which is positioned higher than and a different pipe the tapping tube and the tapping pipe, the pressure relief valve The inlet pipe is bifurcated, and the first end is connected to a pipe separate from the hot water pipe provided so as to be connected to the uppermost part of the hot water storage tank or a high temperature side pipe through which high temperature water flows. The end is also the water pipe Ku is connected to the lower cold side pipe or the hot water storage tank cold water flows, and discharges the inflation water and gas from the pressure relief valve.

  Since the hot water storage type water heater according to the present invention is provided with the pressure relief valve by a pipe different from the hot water discharge pipe, the expanded water discharge process can be performed independently of the hot water discharge operation. Therefore, even when the user tries to take out hot water from a faucet or the like during the expansion water treatment, hot water at an appropriate temperature can be supplied.

Embodiment 1 FIG.
FIG. 1 is a system configuration diagram of the entire hot water storage type hot water heater according to Embodiment 1 of the present invention. In FIG. 1, a hot water storage type water heater according to the first embodiment includes a hot water storage unit 100 and a heat source unit 200. To the hot water storage unit 100, a bathtub 5, a mixing plug 6, and a remote controller 7 are connected. The bathtub 5 is a bathtub for storing hot water supplied from the hot water supply side mixing valve 2b. The mixing plug 6 is a mixing plug that supplies hot water by mixing hot water supplied from the general hot water supply side mixing valve 2a and city water supplied from a water source. For example, a faucet or a shower may be connected. . The remote controller 7 is used to input information to the hot water storage type water heater such as setting the hot water temperature and hot water supply operation to the bathtub, and to display the operation status. A plurality of remote controllers 7 may be installed, such as for baths and kitchens.

  The heat source unit 200 incorporates a heater (not shown) such as a heat exchanger that heats and heats water at a city water temperature (hereinafter referred to as water or low-temperature water) to a target hot water storage temperature. As the heater, for example, a heat pump using HFC or CO2 as a refrigerant is used. Instead of the heat pump, the heating source may be replaced with an electric heater or the like, or the heating source may be built in the hot water storage tank 1.

The hot water storage unit 100 includes a hot water storage tank 1, a general hot water supply side mixing valve 2a, a bath hot water supply side mixing valve 2b (hereinafter, both may be referred to as mixing valves 2a and 2b), a pressure reducing valve 3, a solenoid valve 4, and a pressure. The relief valve 20 is configured by pipe connection. The hot water storage unit 100 is provided with a plurality of sensors (11a, 11b, 12a to 12d, 13a to 13e) which will be described later, and the controller 10 detects the values detected by these sensors, instructions from the remote controller 7, and heat sources. Based on the operating condition of the unit 200, the hot water storage hot water heater is controlled.
The hot water storage tank 1 is made of metal such as stainless steel or resin, and is provided with a heat insulating material (not shown), which can keep hot hot water (hereinafter referred to as high temperature water) for a long time.

  Next, the piping configuration will be described. In addition, each arrow shown in FIG. 1 has shown the moving direction of hot water (low temperature water or high temperature water), and the white arrow has shown discharge | emission of expansion water or gas.

  After passing through the pressure reducing valve 3, the water supplied from the water source is branched into three branches: a pipe connected to the hot water storage tank 1, a pipe connected to the mixing valves 2 a and 2 b, and a pipe connected to the mixing plug 6.

  The water introduced into the lower part of the hot water storage tank 1 is sent to the heat source unit 200, heated to the target temperature by the heat source unit 200, and then supplied to the upper part of the hot water storage tank 1. Here, the circulation of water between the hot water storage tank 1 and the heat source unit 200 is performed using a pump (not shown) built in the heat source unit 200 as power. The pump may be built in the hot water storage unit 100 instead of being built in the heat source unit 200.

  At the uppermost part of the hot water storage tank 1, a take-out part 41 for taking out high-temperature water is provided, and a hot water discharge line 31 and an expanded water discharge line 33 are provided by branching from the branch part 42. The hot water supply pipe 31 distributes high temperature water to the general hot water supply side mixing valve 2a and the bath hot water supply side mixing valve 2b. A water pipe from a water source is also connected to the general hot water supply side mixing valve 2a and the bath hot water supply side mixing valve 2b, and high temperature water and low temperature water are mixed. Hot water passing through the general hot water supply side mixing valve 2a is mixed with water from a water source at the mixing tap 6 and supplied from a faucet or a shower. Hot water passing through the bath hot water supply side mixing valve 2 b is supplied to the bathtub 5 via the electromagnetic valve 4.

  Above the hot water storage tank 1, a pressure relief valve 20 is provided via an expanded water discharge pipe 33. The pressure relief valve 20 is provided at a position higher than the outlet hot water pipe 31. The inlet pipe of the pressure relief valve 20 branches off at the branch part 43, the first end is connected to the expansion water discharge pipe 33, and the second end is connected to the water supply pipe 32. The end of the pipe connected to the outlet side is open to the atmosphere. The water supply pipe 32 is a pipe that guides water supplied from a water source.

  In addition, a check valve 22 and an orifice 21 are provided on the piping from the branching portion 42 to the branching portion 43 in order from the hot water storage tank 1. The check valve 22 is for preventing low temperature water flowing from the water supply pipe 32 from flowing into the hot water storage tank 1. The orifice 21 adjusts the flow resistance of the expanded water discharge pipe 33. Instead of providing the orifice 21, other decompression means may be provided, such as partially narrowing the pipe pipe at the corresponding location or providing a narrow tube at the relevant location.

  In addition, although the case where the number of the mixing plugs 6 is one was illustrated in FIG. 1, you may provide two or more, such as a faucet of a kitchen or a washroom, a currant and shower of a bathroom, for example. Moreover, it is good also as a structure corresponding to each mixing stopper by increasing the number of mixing valves. Moreover, although the hot water storage tank 1 is configured as one, it may be configured such that two or more hot water storage tanks are connected in series or in parallel. The mixing valves 2a and 2b are electric valves that drive the valve body by a drive source such as a servo motor, for example, and have a structure that can control the hot water supply temperature by adjusting the mixing ratio of hot water and water by moving the valve body. Is.

Next, sensors and a control unit provided in the hot water storage unit 100 will be described.
A flow rate sensor 11a is provided on the outlet side of the general hot water supply side mixing valve 2a, and a flow rate sensor 11b is provided on the outlet side of the bath hot water supply side mixing valve 2b. The flow rate sensor 11b measures the flow rate of hot water from the mixing valves 2a and 2b. .
In addition, temperature sensors 12a to 12d are provided for measuring the temperature of hot water flowing in the pipe. The temperature sensor 12a measures the hot water supply temperature on the outlet side of the general hot water supply side mixing valve 2a, and the temperature sensor 12b measures the hot water supply temperature on the outlet side of the bath hot water supply side mixing valve 2b.
Moreover, the temperature sensor 12c for measuring the temperature of the water supplied to mixing valve 2a, 2b is provided in piping from the water source to mixing valve 2a, 2b.
Further, a temperature sensor 12d for measuring the hot water supply temperature is provided in the vicinity of the take-out portion 41 of the hot water storage tank 1. The temperature sensor 12d may be provided on the surface of the can body at the upper part of the hot water storage tank 1 in addition to being provided on the pipe of the take-out portion 41, and the hot water temperature in the upper body of the hot water storage tank 1 may be directly measured. Also good.

  The hot water storage tank 1 is provided with temperature sensors 13 a to 13 e for measuring the hot water temperature, and measures the hot water temperature at each location in the hot water storage tank 1. From these temperature information, the amount of stored hot water stored in the hot water storage tank 1 can be grasped. The temperature sensors 13a to 13e are brazed to the surface of the pipe or tank, welded, screwed, or fixed to the folder, or installed so that the sensor is immersed in the pipe or tank so that the water temperature can be directly measured. You may install using any method.

The control unit 10 is built in the hot water storage unit 100, and includes a measurement unit (not shown) that measures sensors such as temperature and flow rate, and a calculation unit that performs processing such as calculation, comparison, and determination based on the measurement result ( The constituent elements include a drive unit (not shown) for driving valves such as the electromagnetic valve 4 based on the calculation result, and a transmission / reception unit (not shown) for transmitting / receiving operation information with the heat source unit 200 based on the calculation result. .
It also has a built-in storage unit (not shown) that stores the results obtained by the calculation unit, approximate expressions used in calculations, data tables, etc., and these stored contents can be referenced and rewritten as necessary. it can. Each processing such as measurement, calculation, and driving is performed by a microcomputer, and the storage unit is configured by a semiconductor memory or the like.
In addition, the control unit 10 includes an output unit (not shown), displays a processing result by the microcomputer on an LED, a monitor, etc., outputs a warning sound, etc., and communication means (not shown) such as a telephone line, a LAN line, and a radio. To output information to a remote location.
The control unit 10 includes an input unit (not shown), and inputs operation data from the remote controller 7 and switches (not shown) or communication data from a communication means (not shown) such as a telephone line, a LAN line, and a radio. be able to.

FIG. 2 is a control block diagram according to the first embodiment. The control unit 10 is wired or wirelessly connected to the flow sensors 11a and 11b and the temperature sensors 12a to 12d and 13a to 13e via communication cables, respectively, and can exchange signals. The heat source unit 200 and the remote controller 7 are wired or wirelessly connected, and can transmit and receive control signals. The control unit 10 is wired or wirelessly connected to the mixing valves 2 a and 2 b and the electromagnetic valve 4, and is based on information such as information from sensors, the operation status of the heat source unit 200, and operation instructions from the remote controller 7. Then, the operation control of the mixing valves 2a and 2b and the electromagnetic valve 4 is performed.
In the above configuration example, the control unit 10 is built in the hot water storage unit 100, but the hot water storage unit 100 is provided with a main control unit, and the heat source unit 200 is provided with a sub-control unit having a part of the function of the control unit. It is good also as a structure which performs a cooperation process by performing data communication between a main control part and a sub control part. Moreover, it is good also as a structure which equips the remote control 7 with these functions, and the structure which separately arrange | positions the control part which has an equivalent function outside the hot water storage unit 100, if an equivalent function is implement | achieved, the installation etc. It does not ask about composition.

The hot water supply operation in the hot water storage type water heater configured as described above will be described.
Hot water storage in the hot water storage tank 1 is performed by setting a target boiling temperature in advance with the remote controller 7 and boiling the water temperature in the hot water storage tank 1 to the target boiling temperature by the heat pump heat source of the heat source unit 200 in the midnight time zone. In addition, when the amount of hot water storage is insufficient during the daytime, it is possible to operate the heat source unit 200 to store additional hot water in the hot water storage tank 1.

  When hot water is supplied from the hot water storage tank 1 thus stored to the general hot water supply side, the user sets the hot water supply temperature in advance using the remote controller 7. When the user opens the mixing tap 6, the control unit 10 controls the general hot water supply side mixing valve 2 a so that the temperature detected by the temperature sensor 12 a on the general hot water supply side becomes the set hot water temperature. Are mixed to a specified hot water supply temperature (for example, 42 ° C.). As a result, hot water supply is started from the mixing plug 6 at the specified temperature.

  When hot water is supplied to the bathtub 5, the user sets the hot water supply temperature and the amount of hot water supply with the remote controller 7 in advance. Here, the hot water supply method to the bathtub 5 has four patterns of hot water filling, high temperature hot water, additional hot water, and water injection.

First, the hot water filling operation will be described.
When the user presses the “hot water” switch on the remote controller 7, a hot water instruction is output to the control unit 10. Upon receiving the hot water filling instruction, the control unit 10 controls the hot water supply side mixing valve 2b so that the temperature detected by the temperature sensor 12b on the bath side becomes the set hot water supply temperature, and high temperature water and water are designated. Mix so that the hot water temperature is high. Moreover, the solenoid valve 4 is opened and the filling of the hot water to the bathtub 5 is started. After the hot water filling is started, the integrated flow rate is counted by the flow sensor 11b, and the hot water filling is continued until a preset hot water supply amount is reached. When the accumulated hot water amount reaches the set hot water amount, the solenoid valve 4 is closed to complete the hot water filling.

Next, the hot water hot water operation will be described.
When the user presses the “hot hot water” switch on the remote controller 7, an instruction is output to the control unit 10. Upon receiving the hot water hot water instruction, the control unit 10 controls the hot water supply side mixing valve 2b so that the temperature detected by the temperature sensor 12b on the bathtub 5 side becomes high temperature (for example, 60 ° C.). Mix to the specified hot water temperature. Moreover, the solenoid valve 4 is opened and the hot water supply to the bathtub 5 is started. After the hot water supply to the bathtub 5 is started, the integrated flow rate is counted by the flow sensor 11b, and the hot water supply is continued until a certain amount (for example, 20 L) is reached. When the accumulated hot water amount reaches the set hot water amount, the solenoid valve 4 is closed to complete the hot water supply.

Next, the addition hot water operation will be described.
When the user presses the “Additional hot water” switch on the remote controller 7, an instruction is output to the control unit 10. The control unit 10 that has received the additional hot water instruction controls the hot water supply side mixing valve 2b so that the temperature detected by the temperature sensor 12b on the bathtub 5 side becomes the bathtub hot water temperature set by the remote controller 7, and the electromagnetic valve 4 Is opened to start adding hot water to the bathtub 5. After the start of adding hot water to the bathtub 5, the integrated flow rate is counted by the flow sensor 11b, and when reaching a certain amount (for example, 20L), the solenoid valve 4 is closed to complete the adding hot water.

Next, the water injection operation will be described.
When the user presses the “water injection” switch on the remote controller 7, an instruction is output to the control unit 10. Upon receiving the water injection instruction, the controller 10 controls the bath hot water supply side mixing valve 2b so that the temperature detected by the temperature sensor 12b becomes the city water temperature, and opens the electromagnetic valve 4 to start water injection into the bathtub 5. After the start of water injection into the bathtub 5, the integrated flow rate is counted by the flow sensor 11b, and when reaching a certain amount (for example, 20L), the electromagnetic valve 4 is closed to complete the water injection.

When the hot water in the hot water storage tank 1 is boiled to a high temperature during hot water storage, the volume of the water expands. This is because the density of water varies with temperature. For example, when water at 20 ° C. is boiled to 85 ° C., the density is reduced by about 3% and the volume is increased by about 3%. When the volume of water expands in this way, the internal pressure in the water circuit composed of the sealed hot water storage tank 1 and piping and the like increases.
In addition, when boiling low-temperature water to a high temperature, part of the air dissolved in the water is separated into a gas state. This is because the solubility of air in water becomes smaller as the temperature becomes higher. The gas (air) generated in the water circuit causes corrosion to metal parts such as the hot water storage tank 1 and piping constituting the water circuit. In addition, if gas is mixed in hot water, hot water may scatter from the faucet at the end of the hot water, hot water scatters to the surroundings, or unpleasant noise may be generated by the user. Inconvenient phenomena may occur.
For this reason, it is necessary to properly discharge the expanded water and gas from the water circuit.

  FIG. 3 is a schematic view of the main part when discharging the expansion water and gas from the pressure relief valve 20, and the operation of draining the expansion water will be described with reference to FIG.

The gas generated in the hot water storage tank 1 passes through the take-out portion 41 provided at the uppermost part of the hot water storage tank 1 and flows into the expanded water discharge pipe 33. Since the gas flowing into the expansion water discharge pipe 33 is lighter than hot water, it rises further, passes through the check valve 22 and the orifice 21 together with the high temperature water and stays in front of the pressure relief valve 20 as shown in FIG. become.
On the other hand, low temperature water flows in from the water supply pipe 32 branched from the branch part 43. Therefore, between the pressure relief valve 20 and the check valve 22, high temperature water and low temperature water are mixed.

  In the above configuration, when the pressure in the water circuit rises due to the expansion of the hot water and reaches the valve opening set pressure of the pressure relief valve 20, the pressure relief valve 20 is opened, and the expansion water and gas are discharged. For example, during normal times, when the pressure in the hot water storage tank 1 and the pipe connected thereto is maintained at 170 kPa after the pressure reduction by the pressure reducing valve 3, the pressure in the water circuit rises and the pressure relief valve 20 Is reached, for example, 190 kPa, the pressure relief valve 20 is opened, and the gas and hot water on the inlet side of the pressure relief valve 20 are discharged.

  Therefore, even if the hot water expands due to a temperature rise, the internal pressure in the hot water storage tank 1 and the piping circuit connected to the hot water storage tank 1 can always be kept smaller than the valve opening set pressure of the pressure relief valve 20. Further, since the gas staying in front of the pressure relief valve 20 is discharged preferentially, no gas remains in the water circuit.

  Further, since the check valve 22 is provided, it is possible to prevent low temperature water flowing from the water supply pipe 32 from flowing into the hot water storage tank 1.

  Moreover, since the orifice 21 is provided in the path | route from the hot water storage tank 1 upper part to the branch part 43, the quantity of the high temperature water discharged | emitted can be adjusted. That is, by reducing the diameter of the orifice 21 and increasing the flow path resistance, it is possible to reduce the proportion of high-temperature water discharged as expanded water.

As described above, according to the first embodiment, the gas generated when boiling the hot water storage tank can be completely discharged without remaining, so that an inconvenient phenomenon due to the gas remaining in the piping circuit is prevented. It becomes possible.
In addition, since low temperature water is discharged as expanded water and high temperature water is low, loss of hot water storage energy due to high temperature water discharge can be minimized, and this can contribute to improving the efficiency of the hot water supply system.

  In addition, according to the first embodiment, the expansion water discharge pipe 33 constituting the pressure relief mechanism and the tap water pipe 31 connected to the mixing valves 2a, 2b are completely independent, and the mixing valves 2a, 2b Can be controlled completely independently of the expansion water treatment operation by the pressure relief valve 20. Therefore, the opening degree of the mixing valves 2a and 2b is always kept at an opening degree suitable for the hot water supply temperature regardless of whether or not the expansion water is being discharged. Therefore, even if the user starts hot water supply from a faucet or the like in the state where a power failure occurs and the mixing valves 2a and 2b cannot be controlled, there is no possibility that hot hot water or gas will blow out. Further, since the mixing valves 2a and 2b are not controlled for the purpose of discharging the expanded water, the speed of stabilization up to the target temperature at the start of hot water supply is also fast.

In the above description, the pipe connected to the take-out part 41 is branched at the branch part 42 and connected to the hot water discharge line 31 and the first end of the pressure relief valve 20. You may provide separately the taking-out part which connects one edge part, and the taking-out part which connects the hot water discharge pipe line 31. FIG. In this case, it is necessary that the take-out part is provided at a higher position with respect to the take-out part connecting the first end of the pressure relief valve 20 so that all the gas in the hot water storage tank 1 is guided to this take-out part. .
In the above description, the second end of the pressure relief valve 20 is connected to the water supply pipe 32. However, the connection destination of the second end may be a pipe through which low-temperature water flows. You may connect to any place of the pipe line from 3 to the mixing valves 2a and 2b. Further, a new pipe may be provided at the lower part of the hot water storage tank and connected thereto.

  In the above description, the arrangement of the check valve 22 and the orifice 21 has been described with respect to an example in which the check valve 22 and the orifice 21 are provided in order from the hot water storage tank 1 on the pipe from the branching portion 42 to the branching portion 43. . However, the check valve 22 may be provided between the take-out portion 41 and the branch portion 43, and the orifice 21 may be provided between the branch portion 42 and the branch portion 43, and the arrangement of the check valve 22 and the orifice 21 is sufficient. May be reversed.

Embodiment 2. FIG.
In the first embodiment, the example in which the orifice 21 and the check valve 22 are provided on the pipe from the hot water storage tank 1 to the pressure relief valve 20 has been described. However, in the second embodiment, an example in which a mixing valve is used. Will be described. In addition, since it is the same as that of above-mentioned Embodiment 1 except the location regarding expansion water discharge, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 4 is a system configuration diagram of the hot water storage type hot water heater according to the second embodiment. In FIG. 4, at the uppermost part of the hot water storage tank 1, a take-out part 41 for taking out high-temperature water is provided, and a hot water discharge line 31 and an expanded water discharge line 33a are provided branched from the branch part 42. The expansion water discharge pipe 33 a is provided with a mixing valve 23 and a pressure relief valve 20 in order from the hot water storage tank, and the pressure relief valve 20 and the mixing valve 23 are positioned higher than the outlet hot water pipe 31. . The inlet pipe of the pressure relief valve 20 is connected to the outlet side of the mixing valve 23. The mixing valve 23 is connected to a pipe connecting one inlet side from the branch portion 42 and the other inlet side to the water supply pipe 32. The end of the pipe connected to the outlet pipe of the pressure relief valve 20 is open to the atmosphere.

  The high-temperature water boiled in the hot water storage tank 1 is led to the hot water discharge pipe 31 through the take-out part 41 and is branched from the branch part 42 and flows into the mixing valve 23. Further, water flowing through the water supply pipe 32 also flows into the mixing valve 23, and high temperature water and water are mixed by the mixing valve 23 and flow between the outlet of the mixing valve 23 and the inlet of the pressure relief valve 20. The ratio of mixing high-temperature water and water in the mixing valve 23 is adjusted by controlling the valve opening degree according to a command from the control unit 10. At this time, the valve opening degree on the high temperature water side is decreased and the valve opening degree on the water side is increased to increase the ratio of the low temperature water in the pipe between the pressure relief valve 20 and the mixing valve 23. Similarly to the high-temperature water, the gas generated in the hot water storage tank 1 exits the hot water storage tank 1, passes through the mixing valve 23, and stays in front of the pressure relief valve 20 in the expansion water discharge pipe 33a.

  In the above configuration, when the inside of the water circuit reaches the valve opening set pressure of the pressure relief valve 20 due to the expansion of the hot water accompanying boiling in the hot water storage tank 1, the pressure relief valve 20 is opened and the expansion water and gas are discharged. Is done.

  Therefore, even if the hot water expands due to a temperature rise, the internal pressure in the hot water storage tank 1 and the piping circuit connected to the hot water storage tank 1 can always be kept smaller than the valve opening set pressure of the pressure relief valve 20. Further, since the gas staying in front of the pressure relief valve 20 is discharged preferentially, no gas remains in the water circuit.

  Moreover, since the valve opening degree of the high temperature water side is set smaller, the mixing valve 23 can make the ratio of the high temperature water discharged | emitted as expansion water small.

As described above, according to the second embodiment, the gas generated when boiling the hot water storage tank can be completely discharged without remaining, thereby preventing an inconvenient phenomenon due to the gas remaining in the piping circuit. It becomes possible.
Moreover, since low temperature water is discharged as expansion water and high temperature water is small, loss of hot water storage energy due to discharge of expansion water can be minimized, which can contribute to improving the efficiency of the hot water supply system.

  Further, according to the second embodiment, the expansion water discharge pipe 33a constituting the pressure relief mechanism and the tapping pipe 31 connected to the mixing valves 2a and 2b are completely independent, and the mixing valves 2a and 2b Can be controlled completely independently of the expansion water treatment operation by the pressure relief valve 20. Therefore, the opening degree of the mixing valves 2a and 2b is always kept at an opening degree suitable for the hot water supply temperature regardless of whether or not the expansion water is being discharged. Therefore, even if the user starts hot water supply from a faucet or the like in the state where a power failure occurs and the mixing valves 2a and 2b cannot be controlled, there is no possibility that hot hot water or gas will blow out. Further, since the mixing valves 2a and 2b are not controlled for the purpose of discharging the expanded water, the speed of stabilization up to the target temperature at the start of hot water supply is also fast.

  As another method for controlling the opening of the mixing valve 23, the valve opening on the high temperature water side is fully opened in the time zone before the boiling of the hot water storage tank 1 is finished, and the valve opening on the water side is set at other timings. It can also be fully opened. The gas can be efficiently discharged by fully opening the valve on the high temperature water side at the stage where the most gas is generated before the completion of boiling. In addition, the timing of switching the valve opening can be performed by comparing, for example, a heat storage amount (remaining hot water amount) calculated based on temperature information obtained from the temperature sensors 13a to 13e and a target heat storage amount. As a specific example, the valve opening degree on the high temperature water side may be controlled to be fully opened when the target heat storage amount reaches 95%. Alternatively, when any one of the temperature sensors 13a to 13e reaches a predetermined temperature, the valve opening degree on the high temperature water side may be controlled to be fully opened. As a specific example, when the detected value of the temperature sensor 13e reaches 45 ° C., the valve opening degree on the high temperature water side is controlled to be fully opened.

  Moreover, you may provide a non-return valve in the middle of piping which connects the hot water storage tank 1 and the mixing valve 23 similarly to Embodiment 1. FIG. By providing a check valve, even when the opening of the mixing valve 23 is set to an intermediate opening, it is possible to prevent low-temperature water from flowing into the hot water storage tank 1 during hot water boiling operation or hot water. .

Embodiment 3 FIG.
In the third embodiment, an example in which expansion water and gas are discharged using the pressure relief valve 20 and the separation membrane 24 will be described. In addition, since it is the same as that of above-mentioned Embodiment 1 except the location regarding expansion water discharge, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 5 is a system configuration diagram of a hot water storage type water heater according to the third embodiment. In FIG. 5, at the top of the hot water storage tank 1, a take-out part 41 for taking out high-temperature water is provided, branching from a branch part 42, a hot water discharge pipe 31 and a separation membrane 24 are provided. It is located in a place higher than the outlet hot water pipe 31. A gas exhaust pipe 34 is connected to the separation membrane 24, and the end of the pipe connected to the outlet pipe of the separation membrane 24 is open to the atmosphere.

  The separation membrane 24 is a membrane that separates water and air. A membrane having a pore size that allows air molecules to pass but not water molecules, such as a hollow fiber membrane. The separation membrane 24 is provided so that the inlet side (water side) is connected to the take-out portion 41 and the outlet side (air side) is the gas discharge line 34a.

  Moreover, the pressure relief valve 20 is provided in the expansion water discharge pipe 33b provided by being connected to the pipe connected from the water source. The end connected to the outlet pipe of the pressure relief valve 20 is open to the atmosphere.

In the above configuration, normally, the water pressure in the hot water storage tank 1 is applied to the separation membrane 24 by a pipe connected from the take-out portion 41.
Here, when gas is generated with the boiling of the hot water storage tank 1, it passes through the take-out portion 41 provided at the uppermost part of the hot water storage tank 1, and in the vicinity of the separation membrane 24 at a position higher than the hot water discharge pipe 31. Gas gathers. The collected gas passes through the separation membrane 24 due to the water pressure in the hot water storage tank 1, and is discharged to the atmosphere via the gas discharge pipe 34. Since only the gas passes through the separation membrane 24, high temperature water is not discharged.

  Further, when the pressure in the water circuit rises with the boiling of the hot water storage tank 1 and reaches the valve opening set pressure of the pressure relief valve 20, the pressure relief valve 20 opens and low temperature water is discharged as expansion water. The Since the pressure relief valve 20 is not connected to the pipe through which the high temperature water flows, the high temperature water is not discharged as expansion water.

  Therefore, even if the hot water expands due to a temperature rise, the internal pressure in the hot water storage tank 1 and the piping circuit connected to the hot water storage tank 1 can always be kept smaller than the valve opening set pressure of the pressure relief valve 20. Further, since the separation membrane 24 is provided in connection with the take-out portion 41 provided at the uppermost portion of the hot water storage tank 1, the gas in the hot water storage tank 1 is discharged through the separation membrane 24, and the gas remains in the water circuit. Absent.

  As described above, according to the third embodiment, since the separation membrane 24 that selectively discharges only the gas is provided on the pipe connected to the uppermost part of the hot water storage tank 1, all the gas is discharged from the water circuit. Can be discharged. Further, since the pressure relief valve 20 is connected to the pipe through which the low temperature water flows, the high temperature water is not discharged as the expansion water, and there is no loss of hot water storage energy due to the discharge of the expansion water. Therefore, it can contribute to the efficiency improvement of the hot water supply system.

  Further, according to the third embodiment, the gas discharge pipe 34 and the expansion water discharge pipe 33b constituting the pressure relief mechanism and the tap water pipe 31 connected to the mixing valves 2a and 2b are completely independent. . For this reason, the mixing valves 2a and 2b can be controlled completely independently of the gas and expanded water treatment operations. Therefore, the opening degree of the mixing valves 2a and 2b is always kept at an opening degree suitable for the hot water supply temperature regardless of whether or not the expansion water is being discharged. Therefore, even if the user starts hot water supply from a faucet or the like in the state where a power failure occurs and the mixing valves 2a and 2b cannot be controlled, there is no possibility that hot hot water or gas will blow out. Further, since the mixing valves 2a and 2b are not controlled for the purpose of discharging the expanded water, the speed of stabilization up to the target temperature at the start of hot water supply is also fast.

Embodiment 4 FIG.
In the fourth embodiment, an example in which expansion water and gas are discharged using the pressure relief valve 20 and the float valve 25 will be described. In addition, since it is the same as that of the above-mentioned Embodiment 1 except the part regarding an expanded water discharge mechanism, the same code | symbol is attached | subjected and description is abbreviate | omitted.

FIG. 6 is a system configuration diagram of a hot water storage type water heater according to the fourth embodiment. In FIG.
At the uppermost part of the hot water storage tank 1, a take-out part 41 for taking out high-temperature water is provided, branched from the branch part 42, and provided with a tapping pipe 31 and a float valve 25. It is located in a place higher than 31. A gas discharge pipe 34a is connected to the float valve 25, and the end of the pipe connected to the outlet pipe of the float valve 25 is open to the atmosphere.

The float valve 25 is provided in a pipe where the inlet flow path is connected to the take-out portion 41 so that the outlet flow path is the gas discharge pipe 34a.
A float 25 a that floats in water lighter than water is built in the float valve 25. When the inside of the float valve 25 is filled with water, the float 25a is pressed against the upper wall inside the float valve 25 by water circuit internal pressure. When the float 25a is pressed against the upper wall inside the float valve 25, the outlet flow path of the float valve 25 is closed, so that water does not flow out. That is, the structure is such that water does not flow out from the outlet channel of the float valve 25.

  Moreover, the pressure relief valve 20 is provided in the expansion water discharge pipe 33c provided by being connected to the pipe connected from the water source. The end connected to the outlet pipe of the pressure relief valve 20 is open to the atmosphere.

  In the above configuration, when the gas flows into the float valve 25, the float 25a floats on the water, the upper space inside the float valve 25 is filled with the gas, and the float 25a and the float valve 25 are provided in the upper part. The gap with the outlet becomes wider and the gas is discharged. And when all the gas in the float valve 25 is discharged | emitted, the float 25a will raise again and the outlet flow path will be block | closed. Since the outlet channel is closed when the gas is discharged, the high temperature water is not discharged.

  Further, when the pressure in the water circuit rises with the boiling of the hot water storage tank 1 and reaches the valve opening set pressure of the pressure relief valve 20, the pressure relief valve 20 opens and low temperature water is discharged as expansion water. The Since the pressure relief valve 20 is not connected to the pipe through which the high temperature water flows, the high temperature water is not discharged as expansion water.

  Therefore, even if the hot water expands due to a temperature rise, the internal pressure in the hot water storage tank 1 and the piping circuit connected to the hot water storage tank 1 can always be kept smaller than the valve opening set pressure of the pressure relief valve 20. Further, since the float valve 25 is provided by connecting to the take-out portion 41 provided at the uppermost part of the hot water storage tank 1, the gas in the hot water storage tank 1 is discharged through the float valve 25, and the gas remains in the water circuit. Absent.

  As described above, according to the fourth embodiment, the float valve 25 for selectively discharging only the gas is provided on the pipe connected to the uppermost part of the hot water storage tank 1, so that all the gas is discharged from the water circuit. Can be discharged. Further, since the pressure relief valve 20 is connected to the pipe through which the low temperature water flows, the high temperature water is not discharged as the expansion water, and there is no loss of hot water storage energy due to the discharge of the expansion water. Therefore, it can contribute to the efficiency improvement of the hot water supply system.

  Further, according to the fourth embodiment, the gas discharge pipe 34a and the expansion water discharge pipe 33c constituting the pressure relief mechanism and the tap water pipe 31 connected to the mixing valves 2a and 2b are completely independent. . For this reason, the mixing valves 2a and 2b can be controlled completely independently of the gas and expanded water treatment operations. Therefore, the opening degree of the mixing valves 2a and 2b is always kept at an opening degree suitable for the hot water supply temperature regardless of whether or not the expansion water is being discharged. Therefore, even if hot water supply is started in the state where the power failure occurs and the mixing valves 2a and 2b cannot be controlled, there is no possibility that hot hot water or gas will blow out. Further, since the mixing valves 2a and 2b are not controlled for the purpose of discharging the expanded water, the speed of stabilization up to the target temperature at the start of hot water supply is also fast.

It is a system configuration | structure figure of the hot water storage type water heater which shows Embodiment 1 of this invention. It is a control block diagram which shows Embodiment 1 of this invention. It is operation | movement explanatory drawing of the pressure relief valve which shows Embodiment 1 of this invention. It is a system block diagram of the hot water storage type water heater which shows Embodiment 2 of this invention. It is a system block diagram of the hot water storage type water heater which shows Embodiment 3 of this invention. It is a system block diagram of the hot water storage type water heater which shows Embodiment 4 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Hot water storage tank, 2a General hot water supply side mixing valve, 2b Bath hot water supply side mixing valve, 3 Pressure reducing valve, 4 Solenoid valve, 5 Bathtub, 6 Mixing plug, 7 Remote control, 10 Control part, 11a, 11b Flow sensor, 12a, 12b, 12c, 12d temperature sensor, 13a, 13b, 13c, 13d, 13e temperature sensor, 20 pressure relief valve, 21 orifice, 22 check valve, 23 mixing valve, 24 separation membrane, 25 float valve, 25a float, 31 outlet pipe , 32 Water supply line, 33, 33a, 33b, 33c Expansion water discharge line, 34, 34a Gas discharge line, 41 Extraction part, 42, 43 Branch part, 100 Hot water storage unit, 200 Heat source unit.

Claims (5)

A hot water storage tank for storing hot water,
A heat source unit for heating the water in the hot water storage tank and returning it to the hot water storage tank;
A water supply pipe connected to the lower part of the hot water storage tank and supplying water to the hot water storage tank;
A hot water discharge pipe connected to the upper part of the hot water storage tank, for discharging hot water stored in the hot water storage tank ;
In a hot water storage water heater having
A hot water mixing valve provided in the hot water pipe for mixing the low temperature water and the high temperature water from the hot water storage tank;
Before SL and a pressure relief valve provided at a position higher than the hot water pipe,
The pressure relief valve is connected to a pipe different from the outlet pipe provided such that the inlet pipe is branched into two and the first end is connected to the uppermost part of the hot water storage tank or the high temperature side pipe through which high temperature water flows. The second end is connected to the water supply pipe or the low temperature side pipe through which the low temperature water flows or the hot water storage tank lower part,
The hot water storage type hot water heater is characterized in that expansion water and gas are discharged from the pressure relief valve. The hot water storage type water heater according to claim 1, wherein the flow path resistance of the inlet pipe of the pressure relief valve is smaller on the second end side than on the first end side. The hot water storage type hot water heater according to claim 1 or 2, wherein a check valve is provided in a path from a branching portion that divides the inlet pipe of the pressure relief valve into two branches to the uppermost portion of the hot water storage tank. A hot water storage tank for storing hot water,
A heat source unit for heating the water in the hot water storage tank and returning it to the hot water storage tank;
A water supply pipe connected to the lower part of the hot water storage tank and supplying water to the hot water storage tank;
A hot water discharge pipe connected to the upper part of the hot water storage tank, for discharging hot water stored in the hot water storage tank ;
In a hot water storage water heater having
A hot water mixing valve provided in the hot water pipe for mixing the low temperature water and the high temperature water from the hot water storage tank;
Before SL and a pressure relief valve provided at a position higher than the hot water pipe,
The pressure relief valve is connected to the hot water storage tank via a mixing valve provided separately from the hot water mixing valve ,
The mixing valve is connected to a pipe different from the hot water pipe provided such that one inlet side is connected to the uppermost part of the hot water storage tank or a high temperature side pipe through which high temperature water flows, and the other inlet side is connected to the water supply pipe or It is connected to the low temperature side pipe through which low temperature water flows,
The hot water storage type hot water heater is characterized in that expansion water and gas are discharged from the pressure relief valve. A control unit for controlling the opening of the mixing valve is provided,
The hot water storage type hot water heater according to claim 4, wherein the control unit controls the opening degree on the other inlet side to be larger.

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