JP7526694B2 - Hot water supply equipment - Google Patents

Description

The present invention relates to a hot water supply device with an instant hot water function.

A hot water supply system with an instant hot water function has been proposed that includes a water heater that heats hot water to a predetermined temperature, a circulation device that circulates hot water in a circulation path constructed between the downstream part of the hot water supply pipe and the water heater, an expansion tank that absorbs the volumetric expansion of the hot water in the circulation path, a main water supply pipe that introduces water from the water supply pipe to the water heater, a main hot water supply pipe that directs hot water from the water heater to the hot water supply pipe, and a main return pipe that guides hot water from the downstream part of the hot water supply pipe to the circulation device (for example, Patent Document 1).

In the hot water supply system described in Patent Document 1, in order to retrofit a circulation device to the water heater, the circulation device, which is composed of a unit that incorporates components such as water supply piping, a circulation pump, and a pressure relief valve into a housing, is disposed outside the water heater and is connected to the water heater and expansion tank by piping.

JP 2017-116222 A

However, in a hot water supply system such as that described in Patent Document 1, multiple devices must be connected to the water heater at the installation site, which makes it easy for installation defects such as incorrect connection directions and poor connections to occur. In addition, water heaters that have a heating function in addition to a hot water supply function are also used, and such water heaters with multiple functions require not only a burner and heat exchanger for hot water supply, but also a burner and heat exchanger for heating, making them larger in size than water heaters that only have a hot water supply function. For this reason, in limited storage spaces such as the pipe shafts of apartment buildings, it may not be possible to install a circulation device or it may be difficult to connect the water heater and circulation device.

The present invention aims to solve the above problems, and its purpose is to prevent poor installation when installing a hot water supply device with an instant hot water function in a small space.

According to the present invention,
Inside the casing,
A hot water supply side heating means;
A heating means on the heating side;
A water supply passage connected to the hot water supply side heating means;
A hot water supply passage connected to the hot water supply side heating means;
A hot water circulation path that is connected to the hot water supply path and circulates hot water when the hot water supply is stopped;
An instant hot water circulation pump that circulates hot water in the instant hot water circulation path;
a heating circulation path connected to the heating means on the heating side and through which a heat medium circulates;
A heating circulation pump that circulates a heat medium through the heating circulation path;
A hot water supply device is provided that has a hot water liquid heat exchanger that heats hot water circulating through a hot water circulation path by a heat medium circulating through a heating circulation path.

In the above-mentioned hot water supply device, the hot water circulation pump and the hot water liquid heat exchanger for hot water operation are housed inside the casing, so the connection process at the installation site can be reduced. This can reliably reduce construction defects.

In addition, with the above-mentioned hot water supply device, the instant hot water circulation pump, instant hot water liquid heat exchanger, etc. are housed within the casing, so the amount of equipment installed outside the hot water supply device can be reduced. As a result, even when the instant hot water function is added to a hot water supply device that has hot water supply and heating functions, the hot water supply device can be installed in a small storage space and the difficulty of construction can be reduced.

Preferably, the water heater further includes, in the casing,
a hot water supply bypass passage that bypasses the hot water supply side heating means and connects the water supply passage and the hot water supply passage;
A bypass servo is provided in the water supply passage to control a flow rate of water from the water supply passage to the hot water bypass passage;
A water volume sensor is provided in the water supply passage and detects the volume of water flowing through the water supply passage.
The hot water circulation pump is fixedly connected to the bottom plate of the casing.
The hot water supply side heating means is disposed above the hot water circulation pump in the casing,
The bypass servo and the water volume sensor are disposed between the hot water supply side heating means and the hot water circulation pump.

According to the above-mentioned water heating device, even if the water heating device does not have an instant hot water function, there is no need to change the bypass servo, water volume sensor, or bottom plate depending on the water heating device; simply by changing the connecting piping components, it is possible to standardize the parts of multiple types of water heating devices regardless of whether they have an instant hot water function or not.

Preferably, the water heater further includes, in the casing,
A bath circulation path through which bath water in the bathtub circulates;
A bath circulation pump that circulates bath water through the bath circulation path;
A bath liquid-liquid heat exchanger for heating the bath water circulating through the bath circulation path by a heat medium circulating through the heating circulation path,
Both the hot water liquid-liquid heat exchanger and the bath liquid-liquid heat exchanger have a plate-type heat exchanger in which planar flow paths are stacked.

The hot water supply device described above, which has not only hot water supply and heating functions but also a bath reheating function, can house an instant hot water circulation pump and instant hot water liquid-liquid heat exchanger within the casing, reducing the difficulty of installation.

Preferably, the water heater further includes, in the casing,
It has a circuit board that controls the hot water supply operation, heating operation, bath reheating operation, and instant hot water operation.

The above-mentioned hot water supply device eliminates the need to connect circuit boards at the installation site, compared to the case of installing a circulation device as a separate unit, further improving ease of installation. In addition, the circuit boards that control multiple types of operation can be shared.

As described above, the present invention can prevent poor installation when installing a hot water supply device with an instant hot water function in a small space.

FIG. 1 is a schematic diagram showing an example of a hot water supply device according to an embodiment of the present invention. FIG. 2 is an external view of the hot water heater according to the embodiment of the present invention as viewed from the front. FIG. 3 is a perspective view of a main part of the hot water supply device according to the embodiment of the present invention, as viewed from the front. FIG. 4 is a perspective view of the main part of the hot water supply device according to the embodiment of the present invention, as viewed from the rear.

The following describes an example of a hot water supply device according to an embodiment of the present invention, as applied to a hot water supply device that performs a hot water supply operation to supply hot water to a hot water supply terminal such as a faucet installed in a bathroom, kitchen, etc., a heating operation to circulate hot water to a hot water heating terminal (floor heater, warm air heater, etc.), a reheating operation to heat bath water in a bathtub, and an instant hot water operation to circulate and heat hot water while the hot water supply operation is stopped.

Figure 1 is a schematic diagram showing an example of a hot water supply device according to an embodiment of the present invention. The hot water supply device 1 is a hot water supply device in which a tank body 20 equipped with two heating means is arranged in a casing 10 that is installed, for example, in a pipe shaft of an apartment building and communicates with the outside via an air supply port and an exhaust port 7 (not shown). The casing 10 is equipped with a casing body 10a (see Figure 2) having a front opening and a cover (not shown) that closes the front opening of the casing body 10a. In this embodiment, the front opening side is the front side, the opposite side to the front opening side is the back side, and the depth direction when the hot water supply device 1 is viewed from the front side is the front-rear direction, the width direction is the left-right direction, and the height direction is the up-down direction. The inside of the tank body 20 is divided by a partition 21 and is composed of a hot water supply side heating means 30 and a heating/reheating side heating means 40.

The hot water supply side heating means 30 is arranged, from bottom to top, with a hot water supply side burner unit 33, a hot water supply side first heat exchanger 31, and a hot water supply side second heat exchanger 32. The hot water supply side first heat exchanger 31 recovers sensible heat from the exhaust gas discharged from the hot water supply side burner unit 33, and the hot water supply side second heat exchanger 32 recovers latent heat from the exhaust gas discharged from the hot water supply side burner unit 33.

The hot water supply side heating means 30 includes, as fluid flow paths, a water supply path 90 that is connected to the water supply and is connected to the upstream end of the hot water supply side second heat exchanger 32, a connecting path 95 that connects the downstream end of the hot water supply side second heat exchanger 32 and the upstream end of the hot water supply side first heat exchanger 31, a hot water supply path 100 that is connected to a hot water supply terminal P1 such as a faucet and is connected to the downstream end of the hot water supply side first heat exchanger 31, and a hot water supply bypass path 105 that bypasses the water supply path 90 and the hot water supply path 100. With this configuration, water supplied from the water supply to the water supply path 90 is heat exchanged and heated in the hot water supply side second heat exchanger 32 and the hot water supply side first heat exchanger 31 by the combustion exhaust gas discharged from the hot water supply side burner unit 33, and the heated hot water is supplied to the hot water terminal P1 via the hot water supply path 100.

The water supply passage 90 is provided with, in order from the upstream side, a water volume sensor 91 that detects the flow rate of water flowing through the water supply passage 90, a water supply temperature sensor 92 that detects the temperature of water flowing through the water supply passage 90, a water volume servo 93 that changes the opening degree of the water supply passage 90, and a bypass servo 94 that changes the opening degree of the hot water bypass passage 105 that connects the water supply passage 90 and the hot water passage 100. These water element members are arranged between the hot water supply side heating means 30 and the hot water circulation pump 311 as described later. The water flow rate detected by the water volume sensor 91 and the water temperature detected by the water supply temperature sensor 92 are output to the control circuit C1, which will be described later. An outlet water passage 96 that leads water from the waterworks to the hot water supply terminal P1 is branched and connected to the water supply passage 90 upstream of the water volume sensor 91.

The hot water supply line 100 is branched off and connected to the hot water circulation line 300 downstream of the hot water supply bypass line 105, and a part of the hot water circulation line 300 extends outside the casing 10. The hot water circulation line 300 arranged inside the casing 10 is provided with an instant hot water volume sensor 310, an instant hot water circulation pump 311, an instant hot water temperature sensor 312, and an instant hot water liquid heat exchanger 313. The hot water circulation line 300 arranged outside the casing 10 is provided with an air-water separator 314, an expansion tank 315, an overpressure relief valve 316, and a check valve 317. The hot water circulation line 300 arranged outside the casing 10 is connected to a return connection port opened in the bottom plate 11 (see FIG. 2) of the casing body 10a. The flow rate of hot water detected by the instant hot water volume sensor 310 and the temperature of hot water detected by the instant hot water temperature sensor 312 are output to the control circuit C1 described later. In addition, when the hot water supply operation is stopped, hot water is circulated through the instant hot water circulation path 300 by operating the instant hot water circulation pump 311.

The instant hot water liquid-liquid heat exchanger 313 is composed of a plate-type heat exchanger in which a planar flow path through which hot water in the instant hot water circulation path 300 flows and a planar flow path through which hot water in the heating branch circulation path 270 that branches off from the connecting return path 206 of the heating circulation path described below flows are stacked. In the instant hot water liquid-liquid heat exchanger 313, heat exchange (liquid-liquid heat exchange) is carried out between the hot water circulating in the instant hot water circulation path 300 and the hot water circulating in the heating branch circulation path 270, and the hot water circulating in the instant hot water circulation path 300 is heated.

The hot water supply path 100 is provided with, from the upstream side, a heat exchanger temperature sensor 101 that detects the temperature of the hot water discharged from the hot water supply side first heat exchanger 31, and an outlet hot water temperature sensor 103 that detects the temperature of the hot water supplied downstream of the junction with the hot water supply bypass path 105. The hot water temperatures detected by these temperature sensors 101 and 103 are output to the control circuit C1, which will be described later.

A blower fan 70 is provided below the hot water supply side burner unit 33. When the blower fan 70 is operated, air drawn into the casing 10 is supplied to the hot water supply side burner unit 33 and the heating side burner unit 43 described below as combustion air, and the combustion exhaust gas discharged from the hot water supply side burner unit 33 and the heating side burner unit 43 is exhausted from the exhaust port 7. Note that a blower fan may also be provided below the heating side burner unit 43 to supply combustion air to the hot water supply side burner unit 33 and the heating side burner unit 43 individually.

The hot water supply side burner unit 33 is composed of three hot water supply side burner blocks 33a, 33b, and 33c, each having multiple burners, and each hot water supply side burner block 33a, 33b, and 33c is connected to a hot water supply side gas branch line 52 that branches off from a gas supply line (not shown). The gas supply line is provided with a main solenoid valve 51 that opens and closes the gas supply line. The hot water supply side gas branch line 52 is provided with a hot water supply side gas proportional valve 53 that changes the opening degree of the hot water supply side gas branch line 52, and hot water supply side switching valves 54a, 54b, and 54c that individually switch the supply and cut-off of fuel gas to the hot water supply side burner blocks 33a, 33b, and 33c.

In addition, a water filling path 250 branches off from the hot water supply path 100, and the water filling path 250 is connected to a bath return path 251 connected to the bathtub P2. The bath return path 251, together with the bath supply path 252, forms a bath circulation path between the bathtub P2 and the bath liquid heat exchanger 221. A bath connection port for connecting the bath return path 251 and the bath supply path 252 is provided on the bottom plate 11 of the casing body 10a.

In the filling path 250, from the upstream side, there are disposed a filling solenoid valve 261 for opening and closing the filling path 250, a check valve 263 for preventing backflow of hot water from the filling path 250 to the hot water supply path 100, and a filling water volume sensor 262 for detecting the flow rate of hot water supplied from the hot water supply path 100 to the filling path 250. The flow rate of hot water detected by the filling water volume sensor 262 is output to the control circuit C1 described later.

The bath return path 251 is provided with a bath return temperature sensor 225 that detects the temperature of the hot water flowing from the bathtub P2 into the bath return path 251, a bath circulation pump 224 for circulating the hot water in the bathtub P2 through the bath supply path 252 and the bath return path 251, a water level sensor 223 that detects the level of the hot water in the bathtub P2, and a bath water flow switch 222 that detects whether the hot water is flowing at a predetermined flow rate or more in the bath return path 251. In addition, the bath supply path 252 is provided with a bath supply temperature sensor 226 that detects the temperature of the hot water flowing from the bath liquid heat exchanger 221 to the bathtub P2. The flow rate and temperature of the bath water detected by these sensors are output to the control circuit C1 described later. By operating the bath circulation pump 224, bath water is circulated in the bath circulation path that connects the bathtub P2 and the bath liquid heat exchanger 221.

The heating/reheating side heating means 40 is arranged with, from the bottom up, a heating side burner unit 43, a heating side first heat exchanger 41, and a heating side second heat exchanger 42. The heating side first heat exchanger 41 recovers sensible heat from the exhaust gas discharged from the heating side burner unit 43, and the heating side second heat exchanger 42 recovers latent heat from the exhaust gas discharged from the heating side burner unit 43.

The heating/reheating side heating means 40 includes, as fluid flow paths, a heating return path 200 connected to the upstream end of the heating side second heat exchanger 42, a heating forward path 210 connected to the downstream end of the heating side first heat exchanger 41, a communication forward path 205 and a communication return path 206 connecting the downstream end of the heating side second heat exchanger 42 and the upstream end of the heating side first heat exchanger 41 across a cistern 201, a bath branch path 240 branching from the heating forward path 210 and connected to the heating return path 200, and a heating branch circulation path 270 branching from the communication return path 206 and connected to the bath branch path 240. Therefore, in this embodiment, the heating circulation path is configured by these fluid flow paths.

Although not shown, a water supply line (not shown) is connected to the cistern 201, which branches off from the water supply line 90 and is used to replenish the cistern 201 with water. A water supply solenoid valve 203 is provided at the connection between the cistern 201 and the water supply line, and water introduced into the water supply line 90 from the waterworks is supplied to the cistern 201 by opening the water supply solenoid valve 203.

The heating forward path 210 is connected to the high-temperature heating terminal (such as a hot air heater) P3. The connection return path 206 is provided with a heating circulation pump 211 for circulating hot water between the high-temperature heating terminal P3 and the heating/reheating side heating means 40. In addition, a low-temperature branch path 216 branches off from the connection return path 206 from the middle part downstream of the heating circulation pump 211, and is connected to a thermal valve header 212 for connecting the low-temperature heating terminal (such as a floor heater) P4. In addition, the connection return path 206 branches off from the low-temperature branch path 216 downstream, and the heating branch circulation path 270 described above is provided with an instant hot water flow control valve 271 that changes the opening degree of the heating branch circulation path 270 and the instant hot water liquid-liquid heat exchanger 313 described above.

The heating return path 200 is connected to a heating return path 217 that returns hot water from the low-temperature heating terminal P4. With this configuration, by operating the heating circulation pump 211, the hot water flowing through the heating return path 200 is heat-exchanged and heated in the heating side second heat exchanger 42 and the heating side first heat exchanger 41 by the combustion exhaust gas discharged from the heating side burner unit 43, and the heated hot water (heat medium) is circulated and supplied from the heating forward path 210 to each heating terminal P3, P4, the bath liquid-liquid heat exchanger 221, and the immediate hot water liquid-liquid heat exchanger 313. Heating connection ports for connecting these heating return paths 200, the heating forward path 210, the low-temperature branch path 216, and the heating return path 217 are opened in the bottom plate 11 of the casing main body 10a.

The heating forward path 210 is provided with a heating high temperature sensor 213 that detects the temperature of the hot water discharged from the heating side first heat exchanger 41, and the connecting forward path 206 is provided with a heating low temperature sensor 215 that detects the temperature of the hot water supplied from the cistern 201 to the low temperature branch path 216. The hot water temperatures detected by these temperature sensors 213, 215 are output to the control circuit C1, which will be described later.

The heating side burner unit 43 is composed of two burner blocks 43a, 43b, each having multiple burners, and each burner block 43a, 43b is connected to a heating side gas branch path 60 that branches off from the gas supply path. The heating side gas branch path 60 is provided with a heating side gas proportional valve 61 that changes the opening degree of the heating side gas branch path 60, and heating side switching valves 62a, 62b that individually switch the supply and cut-off of fuel gas to the burner blocks 43a, 43b. Therefore, by selectively opening and closing the heating side switching valves 62a, 62b, the heating side burner unit 43 can be switched to one of the capacity stages with different combustion amount ranges.

The bath liquid heat exchanger 221 described above is provided in the bath branch path 240, which branches off from the heating forward path 210 and connects to the heating return path 200. The bath liquid heat exchanger 221 is a plate-type heat exchanger in which a planar flow path through which bath water from the bath return path 251 flows and a planar flow path through which hot water from the heating forward path 210 flows are stacked. In the bath liquid heat exchanger 221, heat exchange (liquid-liquid heat exchange) is performed between the hot water flowing in the bath forward path 252 and the hot water flowing in the bath branch path 240, and the hot water flowing in the bath forward path 252 is heated. The bath branch path 240 is provided with a reheating flow control valve 220 that changes the opening degree of the bath branch path 240. In addition, if the instant hot water liquid heat exchanger 313 and the bath liquid heat exchanger 221 are manufactured from plates of the same configuration except for the number of plates stacked, costs can be reduced.

Inside the tank body 20, a drain receiver 16 is provided to receive the strongly acidic drainage generated on the surfaces of the hot water supply side second heat exchanger 32 and the heating side second heat exchanger 42. Although not shown, a drain outlet pipe is connected to the bottom of the drain receiver 16 to guide the drainage to the drain neutralizer 17. A drain neutralizer is loaded inside the drain neutralizer 17, and the drainage collected in the drain neutralizer 17 through the drain outlet pipe is neutralized by the drain neutralizer. A drain pump 37 is connected to the drain neutralizer 17 to forcibly discharge the neutralized water of the drainage collected in the drain neutralizer 17 to the outside.

A remote control (not shown) installed in the kitchen or bathroom is connected by wire or wirelessly to the control circuit C1 built into the casing 10, and the user can operate the remote control to set the hot water supply temperature in hot water supply operation, the hot water filling temperature in hot water filling operation, the heating temperature in heating operation, the reheating temperature in reheating operation, etc. In addition, although not shown, the control circuit C1 includes a fan motor for the blower fan 70, a main solenoid valve 51, a hot water supply side gas proportional valve 53, a hot water supply side switching valves 54a, 54b, 54c, a heating side gas proportional valve 61, a heating side switching valves 62a, 62b, an ignition electrode that sparks discharges near each flame hole of the hot water supply side burner unit 33 and the heating side burner unit 43, a flame detection sensor that detects the ignition of the hot water supply side burner unit 33 and the heating side burner unit 43, a water volume sensor 91, a water supply temperature sensor 92, a water volume servo 93, a bypass servo 94, a water refilling solenoid valve 203, a hot water filling solenoid valve 26, and a water level sensor 97. 1, the hot water filling water volume sensor 262, the reheating flow control valve 220, the heating circulation pump 211, the thermal valve 212, the bath water flow switch 222, the water level sensor 223, the bath circulation pump 224, the water level electrode of the cistern 201, the heat exchanger temperature sensor 101, the outlet water temperature sensor 103, the heating high temperature sensor 213, the heating low temperature sensor 215, the bath return temperature sensor 225, the bath supply temperature sensor 226, the instant hot water circulation pump 311, the instant hot water volume sensor 310, the instant hot water flow control valve 271, the instant hot water temperature sensor 312, and the drain pump 37 are connected via electrical wiring.

The control circuit C1 has a CPU, memory, interface circuit, etc. (not shown), and is composed of one circuit board 5 at the bottom inside the casing 10 (see FIG. 2). The control circuit C1 performs the function of controlling the overall operation of the water heater 1 by executing the control program for the water heater 1 stored in the memory with the CPU. Therefore, the water heater operation, heating operation, water filling operation, reheating operation, and instant hot water operation can be controlled by one circuit board 5, and the space inside the casing 10 can be saved. In addition, since there is no need to connect the circuit board of the circulation device, which is manufactured as a separate unit to provide the instant hot water function as in the conventional case, to the circuit board inside the casing 10, construction errors when connecting the circuit boards can be prevented. Furthermore, since the water heater operation and heating operation have a common configuration regardless of whether or not there is an instant hot water function, a common circuit board 5 can be used for both water heaters with and without the instant hot water function. This improves the productivity of the circuit board 5.

Figure 2 is an external view showing an example of a hot water supply device according to this embodiment, Figure 3 is a perspective view of the main parts as seen from the front side, and Figure 4 is a perspective view of the main parts as seen from the rear side. Note that some elements have been omitted from these figures to avoid complication.

As shown in Figures 2 to 4, the hot water supply device 1 has a casing body 10a in the shape of a substantially rectangular box with a front opening, and a cover (not shown). The can body 20, which houses the hot water supply side heating means 30 and the heating/reheating side heating means 40, is disposed in the upper part of the casing body 10a. The can body 20 is configured by stacking, from the bottom, the combustion chamber 2 housing the hot water supply side burner unit 33 and the heating side burner unit 43 described above, the first heat exchange chamber 3 housing the hot water supply side first heat exchanger 31 and the heating side first heat exchanger 41, and the second heat exchange chamber 4 housing the hot water supply side second heat exchanger 32 and the heating side second heat exchanger 42. A blower fan 70 is connected to the opening at the bottom of the combustion chamber 2. Also, when viewed from the front, the downstream end of the water supply passage 90 and the upstream end of the connection passage 95 are connected to the right region of the second heat exchange chamber 4, and the upstream end of the hot water supply passage 100 and the downstream end of the connection passage 95 are connected to the right region of the first heat exchange chamber 3. Also, although not shown, the downstream end of the heating return passage 200 and the upstream end of the connection outgoing passage 205 are connected to the left region of the second heat exchange chamber 4, and the upstream end of the heating outgoing passage 210 and the downstream end of the connection return passage 206 are connected to the left region of the first heat exchange chamber 3.

The hot water circulation pump 311, drain pump 37, and bath circulation pump 224 are fixedly connected to the bottom plate 11 of the casing body 10a with fixing screws, and the heating circulation pump 211 is fixedly connected to the left end of the bottom plate 11 via a fixing member. The water supply passage 90 and the hot water supply passage 100 extend downward from the tank body 20, and the lower ends of the water supply passage 90 and the hot water supply passage 100 are respectively connected to a water supply connection port and a hot water supply connection port opened on the bottom plate 11 of the casing body 10a. Connection joints are provided on the underside of the bottom plate 11 of the casing body 10a around the periphery of these connection ports to connect piping outside the casing 10 to the water supply passage 90 and the hot water supply passage 100.

Water element components such as the water volume sensor 91 and bypass servo 94 described above are interposed in the water supply passage 90. These water element components are arranged so as to be located below the can body 20 and above the instant hot water circulation pump 311. Also, below the can body 20, in the rear center, a flat, approximately rectangular instant hot water liquid heat exchanger 313 is arranged in an upright position with its thickness direction located in the front-to-back direction. Also, below the can body 20, above the instant hot water liquid heat exchanger 313, a flat, approximately rectangular bath liquid heat exchanger 221 is arranged in a horizontal position with its thickness direction located in the up-down direction.

A cistern 201 is disposed to the left of the tank body 20 inside the casing body 10a. The previously mentioned drain neutralizer 17 is disposed at the front left lower part of the casing body 10a. Although not shown, the previously mentioned bath connection port and heating connection port are opened in the bottom plate 11 of the casing body 10a, and connection joints for connecting piping are provided on the underside of the bottom plate 11 of the casing body 10a around the periphery of these connection ports. The circuit board 5 constituting the previously mentioned control circuit C1 is disposed at the front right lower part of the casing body 10a.

According to this embodiment, the instant hot water circulation pump 311 and instant hot water liquid heat exchanger 313 for instant hot water operation are housed within the casing 10, so there is no need to connect the hot water supply device to a separate circulation device at the installation site as in the past. This reduces the number of connection steps at the installation site, and ensures that construction defects are reduced.

In addition, according to this embodiment, the instant hot water circulation pump 311, instant hot water liquid heat exchanger 313, etc. are housed within the casing 10, so the amount of equipment installed outside the water heater 1 can be reduced. As a result, even when the instant hot water function is added to a water heater that has a hot water supply function and a heating function, the water heater 1 can be installed in a small storage space and the difficulty of construction can be reduced.

In addition, according to this embodiment, the hot water circulating through the instant hot water circulation path 300 is heated by the hot water circulating through the heating branch circulation path 270, which constitutes part of the heating circulation path, so there is no need to operate the hot water supply side heating means 30, which has a large capacity, to perform instant hot water operation, and instant hot water operation can be performed efficiently. Note that antifreeze may also be used as a heat medium for heating.

In addition, according to this embodiment, the heavy instant hot water circulation pump 311 is fixedly connected to the relatively rigid bottom plate 11 of the casing body 10a, so deflection due to the load of the instant hot water circulation pump 311 and vibration during operation of the instant hot water circulation pump 311 can be suppressed. Even in the case of a hot water supply device without an instant hot water function, there is no need to change the water element components such as the water volume sensor 91 and bypass servo 94 or the bottom plate 11, so parts for multiple types of hot water supply devices can be standardized regardless of whether they have an instant hot water function or not.

In addition, according to this embodiment, the instant hot water liquid heat exchanger 313 and the bath liquid heat exchanger 221 are constructed from plate-type heat exchangers, and even in a hot water supply device 1 that has not only hot water supply and heating functions but also a bath reheating function, the instant hot water circulation pump 311 and the instant hot water liquid heat exchanger 313 can be housed within the casing 10, reducing the difficulty of construction.

In addition, with this embodiment, compared to the conventional case where separate circulation devices are used, there is no need to connect circuit boards at the installation site, which further improves workability. Also, the circuit boards that control multiple types of operation can be shared.

REFERENCE SIGNS LIST 1 hot water supply device 10 casing 11 bottom plate 30 hot water supply side heating means 40 heating/reheating side heating means 90 water supply channel 100 hot water supply channel 300 instant hot water circulation channel 311 instant hot water circulation pump 313 instant hot water liquid-liquid heat exchanger

Claims (4)

Inside the casing,
A hot water supply side heating means;
A heating means on the heating side;
A water supply passage connected to the hot water supply side heating means;
A hot water supply passage connected to the hot water supply side heating means;
A hot water circulation path that is connected to the hot water supply path and circulates hot water when the hot water supply is stopped;
An instant hot water circulation pump that circulates hot water in the instant hot water circulation path;
a heating circulation path connected to the heating means on the heating side and through which a heat medium circulates;
A heating circulation pump that circulates a heat medium through the heating circulation path;
A hot water supply device having a hot water heat exchanger that heats hot water circulating through a hot water circulation path by a heat medium circulating through a heating circulation path. The water heater according to claim 1 further includes:
a hot water supply bypass passage that bypasses the hot water supply side heating means and connects the water supply passage and the hot water supply passage;
A bypass servo is provided in the water supply passage to control a flow rate of water from the water supply passage to the hot water bypass passage;
A water volume sensor is provided in the water supply passage and detects the volume of water flowing through the water supply passage.
The hot water circulation pump is fixedly connected to the bottom plate of the casing.
The hot water supply side heating means is disposed above the hot water circulation pump in the casing,
The hot water supply device, wherein the bypass servo and the water volume sensor are disposed between the hot water supply side heating means and the hot water circulation pump. The water heater according to claim 1 or 2 further comprises:
A bath circulation path through which bath water in the bathtub circulates;
A bath circulation pump that circulates bath water through the bath circulation path;
A bath liquid-liquid heat exchanger for heating the bath water circulating through the bath circulation path by a heat medium circulating through the heating circulation path,
Both the instant hot water liquid-liquid heat exchanger and the bath liquid-liquid heat exchanger are hot water supply devices that have a plate-type heat exchanger in which planar flow paths are stacked. The water heater according to claim 3 further includes:
A hot water supply device having a circuit board for controlling hot water supply operation, heating operation, bath reheating operation, and instant hot water operation.

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