JP6036563B2 - Hot water storage water heater - Google Patents

Description

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

  For example, there is a hot water storage water heater that stores hot water boiled by a heating means such as a heat pump in a hot water storage tank and uses the hot water taken out of the hot water storage tank to supply hot water to a hot water supply destination such as a bathtub, a shower, a kitchen, and a faucet in a bathroom. Widely used.

  Patent Document 1 discloses a water heater that saves water and saves energy by periodically changing the flow rate of hot water to the shower.

JP 2011-252684 A

  As in the technique disclosed in Patent Document 1, a certain amount of water saving effect and energy saving effect may occur by changing the hot water supply flow rate to the shower and periodically reducing the flow rate. However, when the flow rate of the shower is periodically decreased, the rinsing performance may be decreased and it may be difficult to use. In addition, the necessary rinsing time becomes long, and it is considered that sufficient water saving effect and energy saving effect cannot be obtained.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a hot water storage type hot water heater capable of improving energy saving while maintaining ease of use. It is another object of the present invention to provide a highly reliable hot water storage type water heater that can extend the operating life of components.

The hot water storage type hot water heater according to the present invention includes a hot water storage tank for storing hot water, high temperature water taken out from the upper part of the hot water storage tank, and medium hot water taken out from an intermediate part between the upper part and the lower part in the vertical direction of the hot water storage tank. A first mixing means for making the mixing ratio variable, a second mixing means for making the mixing ratio of the first hot water supplied from the first mixing means and the low-temperature water supplied from the water source variable, A means for switching between a constant temperature hot water supply mode in which the temperature of the second hot water supplied from the mixing means is temporally constant and a variable temperature hot water supply mode in which the temperature of the second hot water is temporally varied , and the first mixing in the constant temperature hot water supply mode Means for increasing the operating frequency of the second mixing means compared to the operating frequency of the means, and the first hot water by increasing the operating frequency of the first mixing means compared to the operating frequency of the second mixing means in the variable temperature hot water supply mode. Temperature varies over time It means that a shall comprise a.

  According to the present invention, energy saving can be improved while maintaining ease of use. In addition, it is possible to extend the operating life of the parts, and it is possible to provide a highly reliable hot water storage type water heater.

It is a block diagram which shows the hot water storage type water heater of Embodiment 1 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a hot-water storage type water heater according to Embodiment 1 of the present invention. As shown in FIG. 1, the hot water storage type water heater 35 according to the first embodiment is a tank unit 33, an HP unit 7 that uses a heat pump cycle, and a user interface device that performs a change operation of an operation command or a set value. Remote control device 44. The HP unit 7 and the tank unit 33 are connected to each other via an HP outgoing pipe 14, an HP return pipe 15, and electrical wiring (not shown). The tank unit 33 includes a control means 36. The operations of various valves, pumps and the like provided in the tank unit 33 and the HP unit 7 are controlled by a control means 36 electrically connected thereto. The control means 36 and the remote control device 44 are connected so that they can communicate with each other. Although not shown in the drawings, the remote control device 44 includes a display unit that displays information such as the state of the hot water storage water heater 35, an operation unit such as a switch operated by a user, a speaker, a microphone, and the like.

  The HP unit 7 functions as a heating means for heating the low-temperature water led from the hot water storage tank 8 provided in the tank unit 33. The HP unit 7 connects the compressor 1, the water refrigerant heat exchanger 3, the expansion valve 4, and the air heat exchanger 6 in a ring shape with a refrigerant pipe 5 to constitute a heat pump cycle. The water-refrigerant heat exchanger 3 is for exchanging heat between the refrigerant flowing through the refrigerant pipe 5 and the low-temperature water led from the tank unit 33.

  The tank unit 33 incorporates the following various parts and piping. The hot water storage tank 8 stores hot water. A third water supply pipe 9 c is connected to a water inlet 8 a provided at the lower part of the hot water storage tank 8. Low-temperature water supplied from a water source such as water supply is adjusted to a predetermined pressure by the pressure reducing valve 31 and then flows into the hot water storage tank 8 through the third water supply pipe 9c. A hot water supply pipe 21 a for taking out high-temperature water stored in the hot water storage tank 8 and a hot water supply pipe 13 are connected to the hot water introduction outlet 8 d provided in the upper part of the hot water storage tank 8. Hot water heated using the HP unit 7 flows into the hot water storage tank 8 from the hot water introduction outlet 8d, and low temperature water from the third water supply pipe 9c flows from the water introduction port 8a. In the hot water storage tank 8, hot water is stored by forming a temperature stratification in which the upper side is hot and the lower side is low. A plurality of hot water storage temperature sensors 41, 42, and 43 are attached to the surface of the hot water storage tank 8 at different heights. By detecting the temperature distribution of the hot water in the hot water storage tank 8 with these hot water storage temperature sensors 41, 42, 43, the remaining hot water amount or the heat storage amount in the hot water storage tank 8 is grasped, and the hot water in the hot water storage tank 8 by the HP unit 7 is obtained. The start and stop of the boiling operation are controlled.

  In the tank unit 33, the heat source pump 12 and the use side heat exchanger 20 are built. The heat source pump 12 is a pump for circulating hot water through various pipes to be described later in the tank unit 33, and is provided on the HP outgoing pipe 14. The use-side heat exchanger 20 is a heat exchanger for heating secondary water to be heated (tub water, heating water, etc.) using high-temperature water supplied from the hot water storage tank 8 or the HP unit 7. is there. In the present embodiment, as the secondary side configuration of the use-side heat exchanger 20, a bath piping 27 and a bath return piping 28 for circulating the bath water led out from the bath 30 will be exemplified and described. The use side heat exchanger 20 is installed in the middle of a circulation path formed by the forward piping 27, the return piping 28, and the bathtub 30. Further, a bath circulation pump 29 for circulating bath water and a bath return temperature sensor 38 for detecting the temperature of bath water discharged from the bath 30 are installed in the middle of the bath return pipe 28. In the middle of the bath piping 27, a bath temperature sensor 37 for detecting the temperature of the hot water after the heat exchange from the use side heat exchanger 20 is installed.

  The three-way valve 11 is a flow path switching means having an a port and a b port as inflow ports and a c port as an outflow port. The four-way valve 18 is a flow path switching means having b and c ports that are inflow ports and a and d ports that are outflow ports. The four-way valve 18 is configured to be able to switch the flow path among four paths, ab, ac, bd, and cd. The tank unit 33 includes a water outlet port pipe 10, a hot water introduction pipe 20 a, a first bypass pipe 16, a hot water outlet pipe 20 b, and a second bypass pipe 17. The water outlet port pipe 10 connects a water outlet 8 b provided at the lower part of the hot water storage tank 8 and the a port of the three-way valve 11. The HP forward piping 14 connects the c port of the three-way valve 11 and the inlet side of the HP unit 7. The HP return pipe 15 connects the outlet side of the HP unit 7 and the c port of the four-way valve 18. The hot water supply pipe 13 connects the d port of the four-way valve 18 and the hot water introduction outlet 8 d above the hot water storage tank 8. The first bypass pipe 16 connects the a port of the four-way valve 18 and a hot water inlet 8 c provided between the central part and the lower part of the hot water storage tank 8. The hot water introduction pipe 20 a branches off from the middle of the hot water supply pipe 13 and is connected to the primary side inlet of the use side heat exchanger 20. The hot water outlet pipe 20 b connects the primary side outlet of the use side heat exchanger 20 and the b port of the three-way valve 11. The second bypass pipe 17 branches from between the heat source pump 12 in the HP outgoing pipe 14 and the inlet side of the HP unit 7 and is connected to the b port of the four-way valve 18.

  Furthermore, the tank unit 33 includes a first water supply pipe 9a, a second water supply pipe 9b, a hot water supply pipe 21c, an intermediate temperature water extraction pipe 21b, a hot water mixing valve 22, a bath mixing valve 23, an intermediate temperature water mixing valve 40, and a first hot water supply. A pipe 24 and a second hot water supply pipe 25 are provided. One end of the first water supply pipe 9a is connected to a water source such as a water supply, and the other end of the first water supply pipe 9a is connected to the second water supply pipe 9b and the third water supply pipe 9c via the pressure reducing valve 31, thereby supplying water. A conduit 9 is configured. The second water supply pipe 9 b is branched from the middle and connected to one of the two inlets of the hot water supply mixing valve 22 and one of the two inlets of the bath mixing valve 23. One end of the intermediate temperature water discharge pipe 21 b is connected to the middle height of the hot water storage tank 8, and the other end is connected to one of the two inlets of the intermediate temperature water mixing valve 40. The intermediate warm water take-out pipe 21 b can take out the intermediate warm water stored in the middle of the hot water storage tank 8 and supply it to the intermediate warm water mixing valve 40. The other of the two inlets of the intermediate temperature water mixing valve 40 is connected to the hot water supply pipe 21a. The intermediate temperature water mixing valve 40 has a mixing ratio between the high temperature water taken out from the upper part of the hot water storage tank 8 by the hot water supply pipe 21a and the intermediate temperature water taken out from the middle height of the hot water storage tank 8 by the intermediate temperature water extraction pipe 21b. This corresponds to the first mixing means having a variable function. One end of a hot water supply pipe 21 c is connected to the outlet of the intermediate temperature water mixing valve 40. The other end of the hot water supply pipe 21 c is branched from the middle and connected to the other of the two inlets of the hot water mixing valve 22 and the other of the two inlets of the bath mixing valve 23. In the following description, the warm water supplied from the intermediate warm water mixing valve 40 to the hot water supply pipe 21c is referred to as “first warm water”. The hot water supply pipe 21a is constituted by the hot water supply pipe 21a, the intermediate hot water outlet pipe 21b, and the hot water supply pipe 21c.

  The hot water supply mixing valve 22 has a function of changing the mixing ratio of the first hot water supplied from the intermediate hot water mixing valve 40 through the hot water supply pipe 21c and the low temperature water supplied from the second water supply pipe 9b. Corresponds to means. The outlet of the hot water supply mixing valve 22 is connected to one end of the first hot water supply pipe 24. In the following description, the hot water supplied from the hot water supply mixing valve 22 to the first hot water supply pipe 24 is referred to as “second hot water”. The second hot water is supplied from the first hot water supply pipe 24 via the hot water tap 34 to a faucet (not shown) such as a shower or a currant used by the user.

  The bath mixing valve 23 has a function of changing the mixing ratio of the first hot water supplied from the intermediate hot water mixing valve 40 through the hot water supply pipe 21c and the low temperature water supplied from the second water supply pipe 9b. The outlet of the basin mixing valve 23 is connected to one end of the second hot water supply pipe 25. In the middle of the second hot water supply pipe 25, there are provided a solenoid valve 26 for opening and closing the second hot water supply pipe 25, and a flow sensor 45 for detecting the flow of hot water passing through the second hot water supply pipe 25. The hot water supplied from the bath mixing valve 23 to the second hot water supply pipe 25 flows into the bathtub 30 through the bath forward pipe 27 and the bath return pipe 28.

  The three-way valve 11 has two flow path forms, a form in which the water outlet pipe 10 and the HP outgoing pipe 14 communicate with each other, and a form in which the hot water outlet pipe 20b and the HP outgoing pipe 14 communicate with each other. Switch the hot water flow path. The four-way valve 18 includes a form in which the HP return pipe 15 and the hot water supply pipe 13 communicate with each other, a form in which the HP return pipe 15 and the first bypass pipe 16 communicate with each other, a first bypass pipe 16 and a second bypass pipe 17. Are connected to the hot water supply pipe 13 and the second bypass pipe 17 are connected to each other, and the flow path of the hot water in the tank unit 33 is switched for use.

  Next, the operation of the hot water storage type water heater 35 of the first embodiment will be described. The hot water storage type water heater 35 includes the following two hot water supply modes as hot water supply modes to the first hot water supply pipe 24. One is a constant temperature hot water supply mode, and the other is a variable temperature hot water supply mode. The constant temperature hot water supply mode is a normal hot water supply mode, in which the temperature of the second hot water supplied to the first hot water supply pipe 24 is controlled to be constant over time. In the variable temperature hot water supply mode, the temperature of the second hot water supplied to the first hot water supply pipe 24 is temporally changed to suppress the overall amount of discharged hot water compared to the constant temperature hot water supply mode, thereby exhibiting an energy saving effect. . In general, it is known that human thermal sensation tends to become insensitive when in a constant temperature state, and that there is an effect of obtaining thermal sensation by giving a certain degree of temperature fluctuation. The variable temperature hot water supply mode utilizes this effect. These hot water supply modes can be selected by the user from the operation unit (not shown) of the remote control device 44. Hereinafter, the operation in each mode will be described.

  First, the constant temperature hot water supply mode will be described. When the user discharges hot water (second hot water) having a desired temperature from a shower, a currant, etc., the control means 36 adjusts the mixing ratio of the first hot water and the low-temperature water by the hot water supply mixing valve 22 to obtain the first temperature. Feedback control is performed so that the temperature of the second hot water detected by the hot water supply temperature sensor 39 provided in the hot water supply pipe 24 becomes a target temperature that is the hot water temperature set by the user using the remote controller 44. The hot water supply flow rate fluctuates due to changes in usage conditions (for example, when the flow rate is reduced by changing the number of taps to one from a state where a plurality of taps are used, or by reducing the taps). At this time, the control means 36 fixes the mixing ratio of the warm water mixing valve 40 without performing feedback control, and feedback controls the mixing ratio of the hot water mixing valve 22 to thereby control the temperature of the second warm water. Reach the target temperature. In addition, when the temperature of the medium-temperature water taken out by the medium-temperature water take-out pipe 21b is higher than the target temperature, the control unit 36 opens the medium-temperature water take-out pipe 21b side and fully closes the hot water supply pipe 21a side. The mixing ratio of the medium-temperature water mixing valve 40 is adjusted in advance so that the mixing ratio is 100% and the mixing ratio of the high-temperature water is 0%. In addition, when the temperature of the medium-temperature water taken out from the medium-temperature water extraction pipe 21b is lower than the target temperature, the control unit 36 causes the temperature of the first warm water to be higher than the target temperature by a predetermined temperature (for example, 5 ° C.). In addition, the mixing ratio of the high temperature water from the hot water supply pipe 21 a and the medium temperature water from the intermediate temperature water extraction pipe 21 b is adjusted in advance by the intermediate temperature water mixing valve 40. The temperature of the medium-temperature water taken out from the medium-temperature water take-out pipe 21b is detected by a hot water storage temperature sensor 42 provided at the same height as the connection position of the medium-temperature water take-out pipe 21b to the hot water storage tank 8. Alternatively, a temperature sensor may be provided in the intermediate temperature water extraction pipe 21b. Moreover, the temperature of 1st warm water is detected by the temperature sensor (illustration omitted) provided in the hot water supply piping 21c.

  Next, the variable temperature hot water supply mode will be described. In the variable temperature hot water supply mode, the temperature of the second hot water is temporally changed by operating the hot water supply valve 40 so as to change the mixing ratio of the intermediate hot water mixing valve 40 during the hot water supply. That is, in the variable temperature hot water supply mode, the control unit 36 fixes the mixing ratio of the hot water supply mixing valve 22 without performing feedback control during the hot water supply, and the high temperature water in the intermediate hot water mixing valve 40 is fixed. By changing the mixing ratio with the medium temperature water, the temperature of the first warm water is changed with time. For this reason, even if the hot water mixing valve 22 stops operating, the temperature of the first hot water supplied to the hot water mixing valve 22 varies with time, so that the second flowing out of the hot water mixing valve 22 is second. The temperature of the hot water varies with time. In the variable temperature hot water supply mode of the first embodiment, the temperature of the second hot water is decreased from a state equal to the target temperature in the constant temperature hot water supply mode to a temperature lower by several degrees Celsius than the target temperature, and then increased to the target temperature. The intermediate temperature water mixing valve 40 is operated repeatedly so that the cycle of causing it to repeat, for example, with a period of about 10 seconds. Since the fluctuation range of the hot water supply temperature in the variable temperature hot water supply mode is about several degrees Celsius, it does not give unpleasant feeling to the user such as a shower. On the other hand, since the hot water supply temperature, that is, the temperature of the second hot water is periodically lowered as compared with the target temperature, less energy is used (the amount of hot water stored in the hot water storage tank 8 or the amount of stored heat). For this reason, an energy saving effect is exhibited compared with the constant temperature hot water supply mode. In addition, when the second hot water is supplied to, for example, a shower, the rinsing performance is not affected even if the hot water temperature fluctuates periodically. Therefore, the above energy saving effect is obtained while maintaining the ease of use of the shower. Be

  In the variable temperature hot water supply mode, the user may arbitrarily set values such as a temperature range to be changed from the target temperature to the low temperature side and a cycle period by the remote control device 44. In the above-described example, the temperature fluctuation in the variable temperature hot water supply mode has been described as changing to the low temperature side with respect to the target temperature of the constant temperature hot water supply mode. For example, the reference of the temperature fluctuation is based on the target temperature of the constant temperature hot water supply mode. For example, the temperature may be lower by about 3 ° C., and may be configured to fluctuate in a range of, for example, 2 to 3 ° C. from the reference temperature. According to such a structure, although a user will feel the fluctuation of the tapping temperature more, it does not immediately become uncomfortable and a further energy saving effect is exhibited.

  As described above, in the constant temperature hot water supply mode, the mixing ratio of the medium temperature water mixing valve 40 is fixed without performing feedback control, and the mixing ratio of the hot water mixing valve 22 is feedback controlled. For this reason, in the constant temperature hot water supply mode, the operation frequency of the hot water mixing valve 22 is higher than the operation frequency of the medium temperature water mixing valve 40. On the other hand, in the variable temperature hot water supply mode, the mixing ratio of the hot water mixing valve 22 is fixed without being repeatedly changed, and the temperature of the second hot water is temporally changed by repeatedly changing the mixing ratio of the intermediate hot water mixing valve 40. To fluctuate. For this reason, in the variable temperature hot water supply mode, the operation frequency of the intermediate temperature water mixing valve 40 is higher than the operation frequency of the hot water supply mixing valve 22. For this reason, according to the first embodiment, the operation time and the operation amount of the intermediate warm water mixing valve 40 and the hot water supply mixing valve 22 are not biased to either one. The service life of both the mixing valve 22 can be extended. Therefore, it is possible to provide a highly reliable hot water storage type water heater 35.

  In the first embodiment, the following control may be further performed in addition to the control described above. During the operation in the variable temperature hot water supply mode, the fluctuation range of the temperature of the second hot water detected by the hot water supply temperature sensor 39 provided in the first hot water supply pipe 24 does not become a preset temperature range (for example, 3 ° C.). In this case, it is considered that the intermediate warm water mixing valve 40 is not operating normally. Therefore, after starting the hot water supply in the variable temperature hot water supply mode, the control means 36 sets the temperature fluctuation range of the second hot water detected by the hot water temperature sensor 39 to a preset temperature range within a preset time limit. If this is not the case, it may be determined that the intermediate temperature water mixing valve 40 has failed, and instead of the intermediate temperature water mixing valve 40, the mixing ratio of the hot water supply mixing valve 22 may be controlled to be repeatedly varied. According to such control, even if the intermediate warm water mixing valve 40 is broken, the temperature of the second warm water can be temporally changed in the variable temperature hot water supply mode. When the control unit 36 determines that the intermediate temperature water mixing valve 40 has failed, the control unit 36 displays on the remote control device 44 that the intermediate temperature water mixing valve 40 has failed, and prompts the user for prompt action. It is desirable to notify such.

  In addition, after the start of hot water supply in the constant temperature hot water supply mode, the control means 36 mixes for hot water supply when the temperature of the second hot water detected by the hot water supply temperature sensor 39 does not reach the target temperature within a preset time limit. Control that the temperature of the second hot water reaches the target temperature by determining that the valve 22 has failed and adjusting the mixing ratio of the intermediate temperature water mixing valve 40 instead of the hot water mixing valve 22 by feedback control or the like. You may do it. According to such control, even if the hot water supply mixing valve 22 breaks down, the temperature of the second hot water can be made to reach the target temperature. When the control unit 36 determines that the hot water supply mixing valve 22 has failed, the control unit 36 displays on the remote control device 44 that the hot water supply mixing valve 22 has failed, and prompts the user for prompt action. It is desirable to notify such.

  Moreover, in this invention, you may change the flow volume of 2nd warm water periodically in variable temperature hot water supply mode. In that case, the fluctuation cycle of the flow rate of the second hot water and the fluctuation cycle of the temperature of the second hot water may be different or the same.

DESCRIPTION OF SYMBOLS 1 Compressor, 3 Water refrigerant | coolant heat exchanger, 4 Expansion valve, 5 Refrigerant piping, 6 Air heat exchanger, 7 HP unit, 8 Hot water storage tank, 8a Water inlet, 8b Water outlet, 8c Hot water inlet, 8d Hot water Inlet / outlet, 9 water supply pipe, 9a 1st water supply pipe, 9b 2nd water supply pipe, 9c 3rd water supply pipe, 10 water outlet pipe, 11 three-way valve, 12 heat source pump, 13 hot water supply pipe, 14 HP outgoing pipe, 15 HP return pipe, 16 1st bypass pipe, 17 2nd bypass pipe, 18 four-way valve, 20 utilization side heat exchanger, 20a hot water introduction pipe, 20b hot water outlet pipe, 21 hot water supply pipe, 21a hot water supply pipe, 21b medium hot water Extraction piping, 21c hot water supply piping, 22 hot water mixing valve, 23 bath mixing valve, 24 first hot water piping, 25 second hot water piping, 26 bath solenoid valve, 27 bath piping, 2 Bath return pipe, 29 bath circulation pump, 30 bathtub, 31 pressure reducing valve, 33 tank unit, 34 hot water tap, 35 hot water storage type hot water heater, 36 control means, 37 bath trip temperature sensor, 38 bath return temperature sensor, 39 hot water temperature sensor , 40 Medium hot water mixing valve, 41, 42, 43 Hot water storage temperature sensor, 44 Remote control device, 45 Flow sensor for bath

Claims (4)

A hot water storage tank for storing hot water,
First mixing means for changing a mixing ratio of high-temperature water taken out from the upper part of the hot water storage tank and medium hot water taken out from an intermediate part between the upper part and the lower part in the vertical direction of the hot water storage tank;
Second mixing means for changing the mixing ratio of the first hot water supplied from the first mixing means and the low-temperature water supplied from the water source;
A constant temperature hot water mode for a predetermined second hot water temperature supplied from the second mixing means temporally, and hands stage Ru switching between alternating temperature hot water mode to vary said second hot water temperature in time,
It means for increasing the operating frequency of the second mixing means as compared to the operating frequency of the previous SL first mixing means Te before Symbol constant temperature hot water mode smell,
And means for varying said first hot water temperature by increasing the operating frequency of the first mixing means in comparison with the operating frequency of the temporally second mixing means prior Symbol Te before KihenAtsushi hot water mode smell,
Hot-water storage type water heater with a. It means for controlling said second hot water temperature by adjusting the mixing ratio of fixed to said second mixing means mixing ratio before Symbol first mixing means Te before Symbol constant temperature hot water mode smell,
And means for varying said second hot water temperature temporally by varying the mixing ratio of fixed to said first mixing means mixing ratio before Symbol second mixing means Te said alternating temperature hot water mode smell,
The hot water storage type water heater according to claim 1. After starting the hot water supply by prior to KihenAtsushi hot water mode, when the preset the fluctuation range of the second hot water temperature within the time limit is not a pre-set temperature range, instead of the first mixing means The hot water storage type hot water heater according to claim 1 or 2, further comprising means for changing a mixing ratio of the second mixing means. Before SL after the start hot water supply according to a constant temperature hot water mode, in a case where the temperature of the second hot water within a preset time limit does not reach the target temperature, the mixing ratio of said first mixing means in place of the second mixing means The hot water storage type hot water supply device according to any one of claims 1 to 3, further comprising means for controlling the temperature of the second hot water by adjusting the temperature.

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