JP6249279B2 - Hot water storage system - Google Patents

Description

  The present invention relates to a hot water storage and hot water supply apparatus, and more particularly to an apparatus having a structure that can prevent hot hot water from being discharged when a power failure occurs or a mixing valve fails.

  2. Description of the Related Art Conventionally, hot water storage and hot water supply devices having functions such as hot water supply to hot water heating terminals such as hot water storage, hot water supply, and floor heating panels, hot water supply to a bath, and reheating are widely used. This hot water storage hot water supply device is a hot water storage tank for storing hot water heated by an external heat source device, a water supply passage for supplying low temperature clean water to the hot water storage tank, and a desired hot water supply destination such as a hot water tap for hot water stored in the hot water storage tank. A hot water supply passage for supplying to the bath, a bath hot water supply circuit for performing hot water supply and reheating to the bath, a heat utilization circulation circuit for heating the bath hot water supply circuit, and the like.

  The hot water storage hot water supply apparatus further includes a bypass passage connecting the water supply passage and the hot water passage by bypassing the hot water storage tank, a mixing valve installed at a junction of the bypass passage and the hot water passage, and the like. Thus, the flow rate of hot water flowing through the hot water outlet passage and the flow rate of water flowing through the bypass passage are adjusted and mixed, and hot water having a set temperature is supplied to a desired hot water supply destination.

  By the way, when a power failure occurs or a mixing valve breaks down, hot hot water may be discharged from a hot water tap or the like. In order to solve this problem, for example, in the hot water storage type hot water supply apparatus of Patent Document 1, a branch passage branched from the water supply passage and connected to the hot water passage without passing through the mixing valve is installed in this branch passage. A structure having an on-off valve for avoiding high-temperature hot water is disclosed.

  The on-off valve for avoiding high temperature hot water is configured as a normally open valve that is closed during hot water supply operation and opened during standby for hot water supply or when the power is turned off. Further, the on-off valve for avoiding high temperature hot water can be set to an open state when high temperature hot water is detected during the hot water supply operation. For this reason, when a power failure occurs or the mixing valve breaks down, the high temperature hot water avoidance open / close valve is opened, so water in the water supply passage flows into the hot water passage through the branch passage due to the water supply pressure, By mixing with hot water, hot water can be prevented from being discharged from a hot water tap or the like.

  As a structure for avoiding high temperature hot water, for example, in the hot water storage water heater of Patent Document 2, a branch pipe branched from the bypass pipe is connected to the hot water pipe on the upstream side of the mixing valve, and the branch pipe is connected to the bypass pipe from the bypass pipe. A structure in which a check valve that allows the flow to the hot water piping is installed is disclosed. In this structure, high temperature hot water can be prevented from being discharged by preliminarily mixing with water before reaching the mixing valve to lower the temperature of the hot water.

Japanese Patent No. 5160377 JP 2003-222407 A

  However, in the hot water storage type hot water supply device of Patent Document 1, in order to avoid high temperature hot water at the time of a power failure or when a mixing valve breaks down, there is a part in which a branch passage and a high temperature hot water avoidance on-off valve are additionally installed. In addition to the increase in the number of points, the on-off valve for avoiding high-temperature hot water is an expensive part, and therefore there is a problem that the cost is increased.

  Moreover, in the hot water storage type water heater of Patent Document 2, since the water in the water supply passage constantly flows from the branch pipe into the passage portion upstream of the mixing valve in the hot water passage by the feed water pressure, the mixing valve is also used in normal hot water supply operation. Hot water and water are mixed in advance before reaching the point. For this reason, the hot hot water stored in the hot water storage tank cannot be effectively used, and there is a problem that the operating efficiency of the hot water storage hot water supply apparatus is lowered.

  The object of the present invention is to provide a hot water storage hot water supply apparatus having a structure capable of avoiding high temperature hot water discharge without additionally installing expensive parts, and to hot water before reaching the mixing valve during hot water supply operation. Providing a structure in which water is not mixed, and the like.

The hot water storage and hot water supply apparatus according to claim 1 connects the hot water storage tank, the water supply passage connected to the lower portion of the hot water storage tank, the hot water supply passage connected to the upper portion of the hot water storage tank, the water supply passage and the hot water supply passage. A bypass passage, mixing means for adjusting and mixing the flow rate of hot water flowing through the hot water passage and the flow rate of water flowing through the bypass passage, an auxiliary heat source device installed in the hot water passage, and the auxiliary of the hot water passage A circulation passage branched from a passage portion between a downstream side of the heat source unit and an upstream side of the mixing means and connected to a passage portion on the upstream side of the auxiliary heat source unit of the hot water passage, In a hot water storage and hot water supply apparatus comprising a circulation passage including a part and a circulation means installed in the circulation passage, a connection passage branched from the water supply passage or the bypass passage and connected to the circulation passage, and hot water supply During rolling, a circulation means control means for driving said circulating means such water passage is not performed to the circulation passage from said connecting passage, said circulating passage, heat by hot water flowing through the circulation passage Heat exchange means for heating a medium is installed, and the connection passage is connected to a passage portion between the downstream side of the circulation means and the upstream side of the heat exchange means in the circulation passage. Yes.

  The hot water storage and hot water supply apparatus according to a second aspect is the invention according to the first aspect, wherein the connection passage allows water to pass from the water supply passage or the bypass passage to the circulation passage and from the circulation passage to the water supply passage or the A check means that does not allow water to flow into the bypass passage is provided.

According to the first aspect of the present invention, the connection passage branched from the water supply passage or the bypass passage and connected to the circulation passage, and the circulation so as not to pass water from the connection passage to the circulation passage during the hot water supply operation. A circulation means control means for driving the means, and a heat exchange means for heating the heat medium by hot water flowing through the circulation passage is installed in the circulation passage, and the connection passage is downstream of the circulation means in the circulation passage. Since the hot water is circulated in the circulation passage through the drive of the circulation means during hot water supply operation, the heat exchange means is caused by the resistance of the heat exchange means. Water pressure is surely applied to the circulation passage on the upstream side, and water in the water supply passage or bypass passage is not passed from the connection passage to the circulation passage.

  At the time of standby for hot water supply, the circulation means is not driven and water pressure does not act on the circulation passage, so that water in the water supply passage or bypass passage can be passed from the connection passage to the circulation passage by the water supply pressure. In the event of a power failure or when the mixing valve breaks down, the water in the water supply passage or bypass passage automatically flows into the hot water discharge passage through the connection passage and the circulation passage due to the water supply pressure, so hot hot water from the hot water tap etc. The ejection can be prevented.

  Therefore, during hot water supply operation, hot water stored in the hot water storage tank can be used as it is for hot water supply, so it is possible to prevent a decrease in the operating efficiency of the hot water storage hot water supply device. Therefore, an existing hot water storage hot-water supply apparatus can be provided with a structure for avoiding high-temperature hot water at low cost without additionally installing expensive parts such as an on-off valve for avoiding high-temperature hot water.

  According to the second aspect of the present invention, the connecting passage is provided with a check means that allows water from the water supply passage or bypass passage to the circulation passage and does not allow water from the circulation passage to the water supply passage or bypass passage. Therefore, the check means can reliably prevent the backflow from the circulation passage to the water supply passage or the bypass passage.

It is a schematic block diagram of the hot water storage hot-water supply apparatus which concerns on Example 1 of this invention. It is a schematic block diagram of the hot water storage hot-water supply apparatus at the time of a hot water supply driving | operation. It is a schematic block diagram of the hot water storage hot-water supply apparatus which concerns on Example 2 of this invention. It is a schematic block diagram of the hot water storage hot-water supply apparatus at the time of a hot water supply driving | operation.

  Hereinafter, modes for carrying out the present invention will be described based on examples.

Next, the whole structure of the hot water storage hot water supply apparatus 1 of this invention is demonstrated.
As shown in FIG. 1, a hot water storage hot water supply device 1 has functions such as hot water storage, hot water supply, bathing, etc., a hot water storage tank 2, a combustion-type auxiliary heat source device 3, a heat-utilizing heat exchanger 4, and water supply A passage 5, a hot water passage 6, a heating circulation circuit 7, a bath remedy circuit 8, a heat utilization circulation circuit 9, a control unit 10, etc. are provided, and most of them are integrally housed in an exterior case 11. .

  The hot water storage hot water supply device 1 is configured as a heat pump hot water supply device by combining the heat pump heat source device capable of heating hot water in the hot water storage tank 2 as the external heat source device 12 and the heat pump heat source device and the hot water storage hot water supply device 1. However, a detailed description of the configuration other than the hot water storage and hot water supply device 1 is omitted. The external heat source unit 12 is not limited to the heat pump type heat source unit, and an exhaust heat recovery heat exchanger of the fuel cell power generation unit can be used.

Next, the hot water storage tank 2, the auxiliary heat source unit 3, and the heat-use heat exchanger 4 will be described.
As shown in FIG. 1, the hot water storage tank 2 is composed of a sealed tank capable of storing high-temperature hot water (for example, 65 to 90 ° C.) heated by the external heat source unit 12 to prevent heat dissipation of the stored hot water. The tank is covered with insulation.

  The auxiliary heat source unit 3 is composed of a known gas water heater that incorporates a burner, a heat exchanger, and the like. The auxiliary heat source unit 3 is a unit that receives a command from the control unit 10 and is combusted to heat hot water only in special cases such as when the hot water temperature in the hot water storage tank 2 is lowered.

  The heat-use heat exchanger 4 heats the bath water flowing through the bath memory circuit 8, and the primary-side heat exchange passage portion 4 a that is a part of the heat-use circulation circuit 9 and one of the bath memory circuit 8. The secondary side heat exchange passage part 4b which becomes a part is provided. In this heat utilization heat exchanger 4, heat is exchanged between hot water flowing through the heat utilization circulation circuit 9 and bathtub water flowing through the bath memory circuit 8, and the bathtub water is heated.

Next, the water supply passage 5 will be described.
As shown in FIG. 1, the water supply passage 5 supplies low temperature clean water from a water supply source to the hot water storage tank 2, and has an upstream water supply passage portion 5a, an intermediate water supply passage portion 5b, and a downstream water supply passage portion 5c. ing. An upstream end of the upstream water supply passage portion 5 a is connected to a water source, and a downstream end of the downstream water supply passage portion 5 c is connected to a lower portion of the hot water storage tank 2.

  A bypass passage 15 connected to the tap water passage 6 is branched from between the upstream water supply passage portion 5a and the intermediate water supply passage portion 5b. The bypass passage 15 connects the water supply passage 5 and the hot water supply passage 6 to supply the low temperature clean water of the water supply passage 5 to the hot water supply passage 6, and has an upstream bypass passage portion 15a and a downstream bypass passage portion 15b. ing. A low temperature side opening / closing valve 16 constituting the mixing means 13 is installed in the downstream bypass passage portion 15b.

  A branch passage 17 connected to the heat utilization circulation circuit 9 is branched from between the intermediate water supply passage portion 5b and the downstream water supply passage portion 5c. The branch passage 17 connects the water supply passage 5 and the heat utilization circulation circuit 9 to supply the low temperature clean water in the water supply passage 5 to the heat utilization circulation circuit 9. An open / close valve 18 is installed in the branch passage 17.

Next, the hot water passage 6 will be described.
As shown in FIG. 1, the hot water passage 6 is for supplying hot water stored in the hot water storage tank 2 to a desired hot water supply destination such as a hot water tap. It has a common hot water passage portion 6b, an intermediate hot water passage portion 6c, and a lower hot water passage portion 6d through which the mixed hot water flows. The upstream end of the upper hot water passage portion 6a is connected to the upper part of the hot water storage tank 2. The downstream end of the lower effluent hot water passage portion 6d is connected to the hot water tap.

  A three-way valve 19 is installed between the upper outlet hot water passage 6a and the common hot water passage 6b, and a downstream circulation passage 9c of the heat utilization circuit 9 is connected to the three-way valve 19. This three-way valve 19 is connected / blocked between the upper spilled water passage portion 6a and the common hot water passage portion 6b, and connected / blocked between the downstream circulation passage portion 9c and the common hot water passage portion 6b, and the upper effluent water passage portion. 6a, common hot water passage section 6b, and downstream circulation passage section 9c can be switched to a connected state (all port open).

  A check valve 21 and the auxiliary heat source unit 3 are installed in order from the upstream to the downstream in the common hot water passage 6b. A high temperature side opening / closing valve 22 constituting the mixing means 13 is installed in the intermediate hot water passage 6c. A bypass passage 15 is connected between the intermediate hot water passage portion 6c and the lower effluent hot water passage portion 6d.

Next, the mixing means 13 will be described.
As shown in FIG. 1, the mixing means 13 adjusts and mixes the flow rate of the hot water flowing through the hot water passage 6 and the flow rate of the water flowing through the bypass passage 15, that is, the water and the water so that the hot water temperature becomes the command temperature. It controls the mixing ratio of hot hot water and is composed of a low temperature side on / off valve 16 installed in the bypass passage 15 and a high temperature side on / off valve 22 installed in the hot water passage 6.

Next, the heating circuit 7 will be described.
As shown in FIG. 1, the heating circuit 7 is a closed circuit that circulates hot water between a heat pump heat source machine that is the external heat source machine 12 and the hot water storage tank 2, and includes a forward side passage portion 7 a and a return side passage portion. 7b, the upstream end of the forward passage portion 7a is connected to the lower portion of the hot water storage tank 2, and the downstream end of the return side passage portion 7b is connected to the upper portion of the hot water storage tank 2.

  A bypass passage portion 7c is branched from the middle portion of the forward passage portion 7a to the middle portion of the return side passage portion 7b. A hot water storage switching valve 23 is installed at this branching portion. A heating circulation pump 24 for circulating hot water through the heat pump heat source machine is installed in the forward passage section 7a.

Next, the bath memory circuit 8 will be described.
As shown in FIG. 1, the bath chase circuit 8 is a circuit that circulates bath water in order to chase the bath water of the bath, and has a bath return side passage portion 8a and a bath outlet side passage portion 8b. Yes. A bath circulation pump 26 is installed between the bath return side passage 8a and the bath exit side passage 8b, and the secondary heat exchange passage 4b of the heat-use heat exchanger 4 is installed in the bath exit side passage 8b. ing.

Next, the heat utilization circulation circuit 9 will be described.
As shown in FIG. 1, the heat utilization circulation circuit 9 (corresponding to a circulation passage) is a passage portion (common hot water passage portion) between the downstream side of the auxiliary heat source unit 3 in the hot water passage 6 and the upstream side of the mixing means 13. 6b and the intermediate hot water passage portion 6c) and is connected to a passage portion (between the upper effluent hot water passage portion 6a and the common hot water passage portion 6b) on the upstream side of the auxiliary heat source unit 3 in the hot water passage 6. In addition, a part of the hot water passage 6 (common hot water passage portion 6b) is included.

  That is, the heat utilization circulation circuit 9 includes a common hot water passage portion 6b, an upstream circulation passage portion 9a, an intermediate circulation passage portion 9b, and a downstream circulation passage portion 9c that are common to the hot water passage 6. In the intermediate circulation passage portion 9b, the heat utilization heat exchanger 4 for heating the bath water of the bath chase circuit 8 with hot water flowing through the heat utilization circulation circuit 9 and the conduction state and the shielding state of the heat utilization circulation circuit 9 are selected. A heat-utilizing on-off valve 27 that can be switched at once is installed in order from upstream to downstream. A circulation pump 28 (corresponding to a circulation means) for circulating hot water in the heat utilization circulation circuit 9 is installed in the downstream circulation passage portion 9c.

  When the hot water is circulated in the heat utilization circulation circuit 9 to exchange heat with the bath water, the hot water flows through the auxiliary heat source unit 3 of the common hot water outlet passage 6b through the driving of the circulation pump 28, and the auxiliary heat source unit 3 The hot hot water after being heated flows through the upstream circulation passage portion 9a and is sent to the primary side heat exchange passage portion 4a of the intermediate circulation passage portion 9b. The secondary side heat exchange passage portion 4a passes through the secondary side heat. The hot water exchanged with the bathtub water flowing through the exchange passage portion 4b is returned to the circulation pump 28 through the downstream circulation passage portion 9c.

Next, the connection passage 30 will be described.
As shown in FIG. 1, the connection passage 30 is branched from between the upstream bypass passage portion 15 a and the downstream bypass passage portion 15 b of the bypass passage 15, and is connected to the downstream side of the circulation pump 28 of the heat utilization circulation circuit 9 and the heat utilization heat. It is connected to a passage portion between the upstream side of the exchanger 4 (between the downstream circulation passage portion 9c and the intermediate circulation passage portion 9b). In the connection passage 30, a check valve 31 (corresponding to a check means) that allows water to flow from the water supply passage 5 to the heat utilization circulation circuit 9 and does not allow water flow from the heat utilization circulation circuit 9 to the water supply passage 5. ) Is installed. The connection passage 30 may have a structure branched from the water supply passage 5.

Next, the control unit 10 will be described.
The hot water storage and hot water supply device 1 is controlled by a control unit 10. Detection signals from various temperature sensors, various flow sensors, etc. are transmitted to the control unit 10, and the control unit 10 operates the hot water storage and hot water supply device 1 and the external heat source unit 12, activates / stops various pumps, Controls the switching of the open / close state and the opening degree adjustment, and executes various operations (hot water circulation operation, hot water supply operation, circulation operation, bath reheating operation, etc.).

  In addition, the control unit 10 performs control for driving the circulation pump 28 so that water is not passed from the connection passage 30 to the heat utilization circulation circuit 9 during the hot water supply operation. That is, the control unit 10 drives the circulation pump 28 during the hot water supply operation to execute a circulation operation for circulating hot water in the heat utilization circulation circuit 9 simultaneously with the start of the hot water supply operation. The control unit 10 that controls the circulation pump 28 corresponds to the circulation means control means.

Next, the operation and effect of the hot water storage and hot water supply apparatus 1 of the present invention will be described.
As shown in FIG. 2, during the hot water supply operation, hot water is pushed out from the upper part of the hot water storage tank 2 to the upper effluent hot water passage 6a by the water supply pressure applied to the hot water storage tank 2 as the hot water tap is opened. The hot water flows into the intermediate hot water passage portion 6c through the common hot water passage portion 6b, is mixed with the low temperature clean water supplied from the bypass passage 15 in the mixing means 13, and is adjusted in temperature. Hot water is supplied from the hot water tap through the lower outflow hot water passage portion 6d.

  By the way, only in normal hot water supply operation, clean water flows into the hot water discharge passage 6 from the connection passage 30 via the heat utilization circulation circuit 9 due to the supply water pressure. Therefore, the control unit 10 switches the three-way valve 19 to the all-port open state simultaneously with the start of the hot water supply operation, switches the heat utilization opening / closing valve 27 to the valve open state, and drives the circulation pump 28 to thereby drive the common hot water outlet passage 6b. A circulation operation is performed in which a part of the hot water flowing through the water is poured into the upstream circulation passage portion 9a, and the intermediate circulation passage portion 9b and the downstream circulation passage portion 9c are caused to flow back to the common outlet passage portion 6b.

  Then, a circulation flow is formed in the heat utilization circulation circuit 9, and water pressure acts on the connection portion of the heat utilization circulation circuit 9 with the connection passage 30 by this circulation flow. In particular, the water pressure surely acts on the upstream side of the heat-use heat exchanger 4 in the heat-use heat exchanger 4 due to the resistance of the heat-use heat exchanger 4, so that the clean water of the bypass passage 15 is fed from the connection passage 30 to the heat-use circuit. The hot water flowing through the hot water passage 6 is not mixed with the hot water.

  As described above, the connection passage 30 branched from the water supply passage 5 or the bypass passage 15 and connected to the heat utilization circulation circuit 9, and the water flow from the connection passage 30 to the heat utilization circulation circuit 9 during the hot water supply operation. Is provided with the control unit 10 (circulation means control means) that drives the circulation pump 28 so that hot water is circulated to the heat utilization circulation circuit 9 through the drive of the circulation pump 28 during the hot water supply operation. Then, water pressure acts on the heat utilization circuit 9, and the water in the water supply passage 5 or the bypass passage 15 is not passed through the heat utilization circuit 9 from the connection passage 30.

  At the time of hot water supply standby and high temperature hot water detection during hot water supply operation, the circulation pump 28 is not driven and water pressure does not act on the heat utilization circulation circuit 9, so that water in the bypass passage 15 is heat utilization circulation from the connection passage 30 due to the water supply pressure. It will be in the state where water can be passed to the circuit 9. In the event of a power failure or when the mixing valve breaks down, the water in the bypass passage 15 automatically flows into the hot water supply passage 6 via the connection passage 30 and the heat utilization circulation circuit 9 due to the supply water pressure. It is possible to prevent discharge from a stopper or the like.

  Accordingly, since hot hot water stored in the hot water storage tank 2 can be used as it is for hot water supply during hot water supply operation, it is possible to prevent a decrease in operating efficiency of the hot water storage hot water supply device 1 and during hot water standby, Since it can be automatically set to the avoidance state, the existing hot water storage hot water supply device 1 is made to have a high temperature hot water discharge avoidance structure at low cost without additionally installing expensive parts such as a high temperature hot water avoidance on-off valve. Can do.

  In addition, since the connection passage 30 is provided with a check valve 31 that allows water to flow from the water supply passage 5 to the heat-use circulation circuit 9 and does not allow water to flow from the heat-use circulation circuit 9 to the water supply passage 5. The check valve 31 can reliably prevent the backflow from the heat utilization circulation circuit 9 to the water supply passage 5.

  Furthermore, the heat utilization circulation circuit 9 is provided with a heat utilization heat exchanger 4 that heats the heat medium with hot water flowing through the heat utilization circulation circuit 9, and the connection passage 30 is connected to the circulation pump 28 of the heat utilization circulation circuit 9. Since it is connected to the passage portion between the downstream side and the upstream side of the heat utilization heat exchanger 4, when hot water is circulated through the heat utilization circulation circuit 9 by the circulation pump 28 during the hot water supply operation, the heat utilization heat exchanger 4 It is possible to reliably prevent water pressure from acting on the passage portion upstream of the heat-utilizing heat exchanger 4 by the resistance and flowing water from the connection passage 30 into the heat-utilizing circulation circuit 9.

  Next, a hot water storage and hot water supply apparatus 1A according to a second embodiment in which the hot water storage and hot water supply apparatus 1 according to the first embodiment is partially changed will be described. In the second embodiment, the same components as those in the hot water storage hot water supply apparatus 1 are denoted by the same reference numerals, description thereof is omitted, and only different components are described.

  As shown in FIG. 3, the hot water storage and hot water supply apparatus 1A has functions such as hot water storage, hot water supply, bathing, etc., and includes a hot water storage tank 2, a combustion-type auxiliary heat source device 3, a heat-utilizing heat exchanger 4, and water supply. A passage 45, a hot water passage 46, a heating circulation circuit 7, a bath remedy circuit 8, a heat utilization circulation circuit 49, a control unit 10 and the like are provided. .

Next, the water supply passage 45 will be described.
As shown in FIG. 3, the water supply passage 45 supplies low temperature clean water from a water supply source to the hot water storage tank 2, and includes an upstream water supply passage portion 45 a, an intermediate water supply passage portion 45 b, a downstream water supply passage portion 45 c, and the most downstream. It has a water supply passage 45d. The upstream end of the upstream water supply passage portion 45 a is connected to the water source, and the downstream end of the most downstream water supply passage portion 45 d is connected to the lower portion of the hot water storage tank 2.

  A bypass passage 55 connected to the outlet hot water passage 46 is branched from between the upstream water supply passage portion 45a and the intermediate water supply passage portion 45b. A check valve 56 is installed in the intermediate water supply passage 45 b, and a check valve 57 is installed in the bypass passage 55.

  A connection passage 60 connected to the hot water discharge passage 46 is branched from between the intermediate water supply passage portion 45b and the downstream water supply passage portion 45c. A branch passage 62 connected to the heat utilization circulation circuit 49 is branched from between the downstream water supply passage portion 45c and the most downstream water supply passage portion 45d. Through this branch passage 62, low temperature clean water can be supplied to the heat utilization circuit 49, and conversely, hot water can be returned from the heat utilization circuit 49 to the hot water storage tank 2.

Next, the hot water passage 46 will be described.
As shown in FIG. 3, hot water stored in the hot water storage tank 2 is supplied to a desired hot water supply destination such as a hot water tap, and an upper effluent hot water passage 46 a through which hot hot water flows, a heat utilization circulation circuit 49, A common upstream common hot water passage portion 46b, a downstream common hot water passage portion 46c, an intermediate hot water passage portion 46d, and a lower outflow hot water passage portion 46e through which the mixed hot water flows, and an upstream end of the upper outflow hot water passage portion 46a Connected to the upper part, the downstream end of the lower effluent hot water passage 46e is connected to the hot water tap.

  A three-way valve 63 is installed between the upper outlet hot water passage 46 a and the upstream common hot water outlet passage 46 b, and a downstream circulation passage 49 b of the heat utilization circulation circuit 49 is connected to the three-way valve 63. This three-way valve 63 can be switched between connection / interruption between the upper outlet hot water passage 46a and the upstream common hot water passage 46b and connection / interruption between the downstream circulation passage 49b and the upstream common hot water passage 46b. Is.

  A circulation pump 58 (corresponding to a circulation means) driven during a hot water supply operation and an auxiliary heat source unit 3 capable of reheating the hot water are installed in order from the upstream to the downstream in the upstream common hot water passage section 46b. A connection passage 60 is connected between the upstream common hot water passage portion 46b and the downstream common hot water passage portion 46c.

  A mixing valve 53 (corresponding to mixing means) is installed between the intermediate hot water passage portion 46d and the lower effluent hot water passage portion 46e, and a bypass passage 55 branched from the water supply passage 45 is connected to the mixing valve 53. The mixing valve 53 adjusts and mixes the flow rate of the hot water flowing through the hot water passage 46 and the flow rate of the water flowing through the bypass passage 55 so as to control the hot water temperature to become the command temperature.

Next, the heat utilization circulation circuit 49 will be described.
As shown in FIG. 3, the heat utilization circulation circuit 49 includes a passage portion between the downstream side of the auxiliary heat source unit 3 in the hot water passage 46 and the upstream side of the mixing valve 53 (the downstream common hot water passage portion 46 c and the intermediate hot water passage portion). 46d) and is connected to the upstream side passage portion (between the upper outlet hot water passage portion 46a and the upstream common hot water passage portion 46b) of the auxiliary heat source unit 3 of the hot water passage 46 and the outgoing hot water passage 46. Part (upstream common hot water passage portion 46b and downstream common hot water passage portion 46c).

  That is, the heat utilization circulation circuit 49 includes an upstream common hot water passage portion 46b and a downstream common hot water passage portion 46c, an upstream circulation passage portion 49a, and a downstream circulation passage portion 49b that are common to the hot water passage 46. In the upstream circulation passage portion 49a, the heat utilization heat exchanger 4 that heats the bath water of the bath chase circuit 8 with hot water flowing through the heat utilization circulation circuit 49, and the conduction state and the shielding state of the heat utilization circulation circuit 49 are selected. A heat-use opening / closing valve 65 that can be switched in a single manner is installed in order from the upstream to the downstream. A branch passage 62 is connected between the upstream circulation passage portion 49a and the downstream circulation passage portion 49b.

  When hot water is circulated in the heat utilization circulation circuit 49 to exchange heat with the bathtub water, the hot water flows through the auxiliary heat source unit 3 of the upstream common hot water outlet passage 46b through the driving of the circulation pump 58, and this auxiliary heat source unit 3 The hot hot water after being heated by the air flows through the downstream common tap water passage portion 46c and is sent to the primary side heat exchange passage portion 4a of the upstream circulation passage portion 49a. The hot water exchanged with the bathtub water flowing through the side heat exchange passage 4b is returned to the circulation pump 58 through the downstream circulation passage 49b.

Next, the connection passage 60 will be described.
As shown in FIG. 3, the connection passage 60 is branched from the water supply passage 45, and a passage portion (upstream common) between the downstream side of the circulation pump 58 of the heat utilization circulation circuit 49 and the upstream side of the heat utilization heat exchanger 4. Between the hot water passage 46b and the downstream common hot water passage 46c). In the connection passage 60, a check valve 61 (corresponding to a check means) that allows water to flow from the water supply passage 45 to the heat-use circulation circuit 49 and does not allow water to flow from the heat-use circulation circuit 49 to the water supply passage 45. ) Is installed. The connection passage 60 may have a structure branched from the bypass passage 55.

Next, the control unit 50 will be described.
The hot water storage and hot water supply apparatus 1 </ b> A is controlled by the control unit 50. Detection signals from various temperature sensors, various flow sensors, and the like are transmitted to the control unit 50. The control unit 50 operates the hot water storage and hot water supply apparatus 1A and the external heat source unit 12, operates and stops various pumps, and controls various valves. Controls the switching of the open / close state and the opening degree adjustment, and executes various operations (hot water circulation operation, hot water supply operation, circulation operation, bath reheating operation, etc.).

  The control unit 50 executes control for driving the circulation pump 58 so that water is not passed from the connection passage 60 to the heat utilization circulation circuit 49 during the hot water supply operation. That is, the control unit 50 drives the circulation pump 58 during the hot water supply operation, and the control unit 50 that controls the circulation pump 58 corresponds to the circulation means control means.

Next, the operation and effect of the hot water storage and hot water supply apparatus 1A of the present invention will be described.
As shown in FIG. 4, at the time of hot water supply operation, hot water from the upper part of the hot water storage tank 2 to the upper effluent hot water passage 46a by the supply water pressure applied to the hot water storage tank 2 and driving of the circulation pump 58 as the hot water tap is opened. This hot hot water that is pushed out flows into the intermediate hot water passage portion 46d through the upstream common hot water passage portion 46b and the downstream common hot water passage portion 46c, and the low temperature water supplied from the bypass passage 55 in the mixing valve 53. The temperature is adjusted by mixing, and the temperature-adjusted hot water is supplied from the hot water tap through the lower outlet hot water passage 46e.

  By the way, when the circulation pump 58 is driven, the pump pressure acts on the hot water supply passage 46 in addition to the supply water pressure. That is, a water pressure higher than the supply water pressure by the pump pressure acts on the connection portion of the hot water passage 46 with the connection passage 60. Since the check valve 61 is installed in the connection passage 60 at the connection portion of the water supply passage 45 with the connection passage 60, only the supply water pressure acts.

  For this reason, since a higher water pressure acts on the connection portion of the hot water passage 46 with the connection passage 60 than the connection portion of the water supply passage 45 with the connection passage 60, the heat utilization circulation is compared with the first embodiment. Even if hot water is not circulated through the circuit 49, the clean water of the water supply passage 45 does not flow into the hot water passage 46 from the connection passage 60 and is not mixed with hot hot water flowing through the hot water passage 46. The connection passage 60 is connected between the upstream common hot water passage portion 46b and the downstream common hot water passage portion 46c. However, the connection passage 60 is not particularly limited to this position, and the circulation pump 58 is driven to drive the hot water passage 46. Since the water pressure is higher than the water pressure of the water supply passage 45, it may be connected to the middle portion of the intermediate hot water passage portion 46d.

  At the time of hot water supply standby and high temperature hot water detection during hot water supply operation, the circulation pump 58 is not driven and water pressure does not act on the hot water discharge passage 46 (part of the heat utilization circulation circuit 49), so the water in the water supply passage 45 is supplied with water supply pressure. As a result, water can be passed from the connection passage 60 to the hot water passage 46 (a part of the heat utilization circulation circuit 49). In the event of a power failure or when the mixing valve fails, the water in the water supply passage 45 automatically flows into the hot water supply passage 46 through the connection passage 60 due to the supply water pressure, so that hot hot water is discharged from a hot water tap or the like. Can be prevented. Other configurations, operations, and effects are the same as those in the first embodiment, and thus description thereof is omitted.

Next, a mode in which the first and second embodiments are partially changed will be described.
[1] The operation of circulating hot water in the heat utilization circulation circuits 9 and 49 during the hot water supply operation in the first and second embodiments is not limited to the bath remedy circuit 8, and is supplied to a floor heating panel, a bathroom dryer, or the like. It may be a hot water heating circuit that circulates heating water to be circulated, and can be changed as appropriate.

[2] In addition, those skilled in the art can implement the invention in various forms added to the first and second embodiments without departing from the spirit of the present invention, and the present invention includes such modifications. It is included.

1,1A Hot water storage hot water supply equipment 2 Hot water storage tank 3 Auxiliary heat source machine 4 Heat-utilizing heat exchanger
5,45 Water supply passage 6,46 Hot water passage 9,49 Heat utilization circulation circuit (circulation passage)
10, 50 control unit (circulation means control means)
13, 53 Mixing means 15, 55 Bypass passages 28, 58 Circulation pump (circulation means)
30, 60 Connection passage 31, 61 Check valve (check means)

Claims (2)

A hot water storage tank, a water supply passage connected to the lower portion of the hot water storage tank, a hot water passage connected to the upper portion of the hot water storage tank, a bypass passage connecting the water supply passage and the hot water supply passage, and the hot water passage Mixing means for adjusting and mixing the flow rate of hot water and the flow rate of water flowing through the bypass passage, an auxiliary heat source device installed in the hot water passage, the downstream side of the auxiliary heat source device in the hot water passage and the mixing means A circulation passage that is branched from a passage portion between the upstream side of the outlet and connected to a passage portion on the upstream side of the auxiliary heat source unit of the outlet hot water passage, and includes a part of the outlet hot water passage, In the hot water storage and hot water supply apparatus provided with a circulation means installed in the circulation passage,
Driving the circulation means from the connection passage branched from the water supply passage or the bypass passage and connected to the circulation passage so that water does not pass from the connection passage to the circulation passage during hot water supply operation and a circulation means control means for,
The circulation passage is provided with heat exchange means for heating the heat medium with hot water flowing through the circulation passage,
The hot water storage hot-water supply apparatus , wherein the connection passage is connected to a passage portion between the downstream side of the circulation means and the upstream side of the heat exchange means in the circulation passage .   The connection passage is provided with check means that allows water to flow from the water supply passage or the bypass passage to the circulation passage and does not allow water flow from the circulation passage to the water supply passage or the bypass passage. The hot water storage hot-water supply apparatus according to claim 1.