JP2002286285A - Hot-water supplier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-water supplier, capable of supplying hot-water of a desired temperature from the initial period of starting of hot-water supply and capable of supplying a desired amount of heat to a heat consuming terminal or the like as soon as possible. SOLUTION: The hot-water supplier is provided with a heat exchanger for supplying hot-water 4, which heats water supplied through a feed water passage 1 by the combustion of a burner 2 and supplies the same into a hot-water supplying passage 3, and a heat exchanger 7 for fluid, which heats an objective fluid for heating which is supplied through an inlet passage 5 by the combustion of the burner 2 and discharges the same into an outlet passage 6, both of which are formed integrally under a condition that heat is conducted to each other, and a control means for controlling the combustion of the burner 2. When the starting condition of heat retaining is satisfied under a condition that the supply of water to the heat exchanger for supplying hot-water 4 is stopped and the supply of heating objective fluid to the heat exchanger for fluid 7 is stopped, the control means carries out temperature retaining control process wherein the combustion of the burner 2 is started to retain a temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply heat exchanger for heating water supplied through a water supply passage by burning a burner to supply hot water to the hot water supply passage, and to supply the heat-supplied fluid supplied through the inlet passage to the burner. A heat exchanger for fluid which is heated by the combustion of the fluid and flows out to the outlet path is provided. The heat exchanger for hot water supply and the heat exchanger for fluid are integrally formed in a state of conducting heat to each other, and The present invention relates to a hot water supply device provided with control means for controlling the combustion of water.

[0002]

2. Description of the Related Art In such a hot water supply apparatus, a heat exchanger for hot water supply and a heat exchanger for fluid are integrally formed in a state of conducting heat mutually. For example, a heat exchanger for fluid is supplied from a bathtub. It is configured to heat bath tub hot water supplied through the road and supplied into the bath tub through the outgoing route, so that hot water supply and reheating of the bath tub hot water are performed by a single burner, thereby reducing the size and cost of the device. It is configured to achieve the following. Further, in this type of hot water supply apparatus, the water supply to the hot water supply heat exchanger is performed by configuring the hot water supply heat exchanger and the fluid heat exchanger to conduct heat to each other. When the supply of the fluid to be heated to the heat exchanger is stopped, or when the supply of the fluid to be heated to the heat exchanger for fluid is performed and the supply of water to the heat exchanger for hot water supply is stopped. In the single heating state, the fluid to be heated in the fluid heat exchanger and the hot water in the hot water supply heat exchanger are prevented from boiling (for example, Japanese Patent Application Laid-Open No. H11-14198).
No. 9).

[0003] The configuration of the heat exchanger for hot water supply and the heat exchanger for fluid will be described in more detail. A heat transfer tube for hot water supply through which hot water flows in the heat exchanger for hot water supply and a fluid to be heated in the heat exchanger for fluid are added. The fluid heat transfer tube to be passed may be made to contact a part of the larger diameter inner peripheral portion and a portion of the smaller diameter outer peripheral portion of the hot water supply heat transfer tube and the fluid heat transfer tube. A part of the outer peripheral part of the heat transfer pipe for hot water supply and a part of the outer peripheral part of the heat transfer pipe for fluid are brought into contact with each other, so that the heat exchanger for hot water supply and the heat exchanger for fluid are thermally conducted to each other. .

[0004]

In the above-described conventional hot water supply apparatus, the hot water supply heat exchanger and the fluid heat exchanger are constructed so as to conduct heat to each other, so that the hot water or the fluid in the hot water supply heat exchanger can be obtained. Of the fluid to be heated in the heat exchanger is prevented, but the heat exchanger for hot water supply and the heat exchanger for fluid are configured to conduct heat to each other. If heat is applied to only one of the heat exchanger for fluids and the heat exchanger for fluids, the heat is also conducted to the other side. Therefore, when heat is to be applied by the hot water supply heat exchanger, part of the heat is taken away by the fluid heat exchanger, and the temperature of the hot water heated by the hot water supply heat exchanger rises. When it is slow or when heat is to be applied by the fluid heat exchanger, part of the heat is taken away by the hot water supply heat exchanger, and the heat of the fluid to be heated is heated by the fluid heat exchanger. There is a risk that the rise in temperature will be delayed.

In particular, the heat transfer tube for hot water supply and the heat transfer tube for fluid
Among the heat transfer pipes for hot water supply and the heat transfer pipes for fluid, those in which a part of the inner periphery of the larger diameter and a part of the outer periphery of the smaller diameter are brought into contact with each other may be used. Of the fluids flowing through the heat transfer tube on the smaller diameter side, the delay of the temperature rise is remarkable because the larger diameter is heated and then the smaller diameter is heated. Become.

In the above-described conventional hot water supply apparatus, the temperature of hot water heated in the hot water supply heat exchanger rises slowly, or the temperature of the fluid to be heated heated in the fluid heat exchanger rises. If it is late, hot water at a desired temperature cannot be supplied from the beginning of hot water supply, or it may take time to supply a desired amount of heat to a heat consuming terminal or the like.

By the way, in a hot water supply device, it is desired to supply hot water at a desired temperature from the beginning of hot water supply, and it is possible to improve the usability of the device by responding to the demand. If it becomes impossible to supply hot water at a desired temperature from the start of hot water supply, it becomes impossible to meet the demand for hot water at a desired temperature, and the device may be inconvenient to use.

The present invention has been made in view of such a point, and an object of the present invention is to supply hot water at a desired temperature from the beginning of hot water supply and to supply a desired amount of heat to a heat consuming terminal or the like as quickly as possible. Another object of the present invention is to provide a hot water supply device that can perform the hot water supply.

[0009]

According to the first aspect of the present invention, there is provided a hot water supply system in which water supplied through a water supply passage is heated by burning a burner and supplied to the hot water supply passage. A heat exchanger, and a fluid heat exchanger that heats the fluid to be heated supplied through the inlet by burning the burner and flows out to the outlet, and the heat exchanger for hot water supply and the heat exchanger for fluid are provided. Are formed integrally with each other in a state where they conduct heat with each other, and a control unit for controlling combustion of the burner is provided, wherein the control unit supplies water to the hot water supply heat exchanger. In a state in which the supply of the fluid to be heated to the fluid heat exchanger is stopped and the condition for starting the heat retention is satisfied, a heat retention control process for starting combustion of the burner and keeping the temperature is performed. Is composed .

That is, the control means determines that the condition for starting heat retention is satisfied in a state where the supply of water to the heat exchanger for hot water supply is stopped and the supply of the fluid to be heated to the heat exchanger for fluid is stopped. The control means is configured to execute the heat retention control process for starting the combustion of the burner and keeping the temperature warm, so that when the condition for starting the heat retention is satisfied, the control means burns the burner and causes the hot and cold water in the hot water supply heat exchanger. In addition, it becomes possible to keep the fluid to be heated in the fluid heat exchanger warm, and at the beginning of hot water supply, it becomes possible to supply hot water and to start heat supply to a heat consuming terminal and the like. Initially, it is possible to supply a heated fluid to be heated.

Therefore, it is possible to provide a hot water supply apparatus which can supply hot water at a desired temperature from the beginning of hot water supply and can supply a desired amount of heat to a heat consuming terminal as quickly as possible.

According to the second aspect of the present invention, the control means is configured to maintain the temperature of the hot and cold water in the hot water supply heat exchanger at a target set temperature as the heat retention control process.

In other words, when the condition for starting heat retention is satisfied, the control means can burn the burner to keep the water in the heat exchanger for hot water supply at the target set temperature.
At the beginning of hot water supply, hot water kept at the target set temperature can be supplied, and hot water can be supplied at a desired temperature from the beginning of hot water supply. Therefore, it is possible to meet a demand for supplying hot water at a desired temperature from the beginning of hot water supply, and to improve the usability of the apparatus.

According to the third aspect of the present invention, the hot water supply heat exchanger includes a hot water supply sensible heat exchange section that recovers the sensible heat of the combustion exhaust gas from the burner, and the hot water supply sensible heat exchange section. A hot water supply latent heat exchange unit that is disposed on the downstream side in the flow direction of the combustion exhaust gas of the burner and recovers latent heat of the combustion exhaust gas of the burner. A fluid sensible heat exchange section for recovering the sensible heat of the flue gas of the burner; and a sensible heat exchange section for the fluid disposed downstream of the sensible heat exchange section for the fluid in the flow direction of the burner flue gas. And a fluid latent heat exchange section for recovering the latent heat of the fluid.

That is, the hot water supply heat exchanger includes a hot water supply sensible heat exchange section and a hot water supply latent heat exchange section, and the fluid heat exchanger comprises a fluid sensible heat exchange section and a fluid heat exchange section. The heat exchanger for hot water supply can collect not only the sensible heat of the flue gas but also the latent heat of the flue gas, and the fluid heat exchanger. However, in addition to the sensible heat of the flue gas, the latent heat of the flue gas can be recovered, and the efficiency of the entire device can be effectively improved. It becomes possible.

According to the fourth aspect of the present invention, the heat exchanger for hot water supply is provided with a heat transfer tube for hot water supply for flowing hot and cold water in the heat exchanger for hot water supply, and the heat exchanger for fluid is provided. The heat exchanger for fluid is configured to include a heat exchanger tube for fluid that allows the fluid to be heated to flow in the heat exchanger for fluid, and the heat exchanger for hot water supply and the heat exchanger for fluid are configured as the heat exchanger tube for hot water supply. The fluid heat transfer tube, the hot water supply heat transfer tube and the fluid heat transfer tube, by contacting a portion of the larger diameter inner peripheral portion and a portion of the smaller diameter outer peripheral portion of each other, It is integrally formed in a state of conducting heat.

That is, the structure according to claim 4 specifies the structure of the heat exchanger for fluid and the heat exchanger for hot water supply in claim 1 described above, and the heat transfer tube for hot water supply and the heat transfer tube for fluid are specified. Of the heat transfer tube for hot water supply and the heat transfer tube for fluid,
A part of the inner periphery of the larger diameter and a part of the outer periphery of the smaller diameter are brought into contact with each other, so that the heat exchanger for hot water supply and the heat exchanger for fluid are integrated in a state in which they conduct heat to each other. Is formed. Then, in a single heating state in which the fluid (water or the fluid to be heated) is supplied to only one of the hot water supply heat exchanger and the fluid heat exchanger, or in the above-described heat retention control process, the inside of the hot water supply heat exchanger Heat of the hot and cold water to the fluid to be heated in the heat exchanger for fluid, and conversely, the heat of the fluid to be heated in the heat exchanger for fluid to the hot water in the heat exchanger for hot water supply This makes it possible to prevent the fluid to be heated in the heat exchanger for fluid and the hot water in the heat exchanger for hot water supply from boiling.

According to the fifth aspect of the present invention, the heat transfer tube for fluid is configured to have a larger diameter than the heat transfer tube for hot water supply, and the fluid to be heated is transferred to the heat exchanger for fluid by the heat exchanger. Fluid circulating means for circulating with a consuming terminal or circulating in a fluid circulating circuit including a heating target fluid bypass which supplies the heating target fluid on the outlet to the inlet is provided, and the control means is provided. During the execution of the heat retention control process, the fluid circulation means is operated.

That is, by the cooperation with claim 4,
The fluid heat transfer tube is configured to be larger in diameter than the hot water supply heat transfer tube, and configured to contact a part of an inner peripheral portion of the fluid heat transfer tube and a part of an outer peripheral portion of the hot water supply heat transfer tube. When the burner is burned, first, the fluid to be heated of the fluid heat transfer tube is heated, and then the hot water of the hot water supply heat transfer tube is heated, and the heating in the fluid heat exchanger is started. If the target fluid does not boil, the water in the hot water supply heat exchanger will not boil. Therefore, the control means
Since the fluid circulating means is configured to be operated during the execution of the heat retention control process, the bypass passage for the fluid to be heated which supplies the fluid to be heated from the outgoing path to the inflow path during the execution of the heat retention control process. Or the entirety of the fluid to be heated circulating in the fluid circulation circuit including the fluid heat exchanger and the bypass by causing the water in the heat exchanger for hot water supply to rise to an appropriate temperature evenly. Can be kept warm.

To summarize the above, by preventing the fluid to be heated in the heat exchanger for fluid from boiling, as a result, the boiling water in the heat exchanger for hot water supply can be prevented from boiling. Hot water in the heat exchanger and the entire fluid to be heated circulating in the fluid circulation circuit can be kept warm.

According to the sixth aspect of the present invention, the hot water supply heat exchanger is provided with a hot water supply heat transfer tube through which hot and cold water flows in the hot water supply heat exchanger, and the fluid heat exchange pipe is provided. The heat exchanger for fluid is configured to include a heat exchanger tube for fluid that allows the fluid to be heated to flow in the heat exchanger for fluid, and the heat exchanger for hot water supply and the heat exchanger for fluid are configured as a heat exchanger tube for hot water supply. A part of the outer peripheral part and a part of the outer peripheral part of the fluid heat transfer tube are brought into contact with each other, and are integrally formed in a state of conducting heat mutually.

That is, the structure according to claim 6 specifies the structure of the heat exchanger for fluid and the heat exchanger for hot water supply in claim 1 described above, wherein the heat exchanger for hot water supply and the heat exchanger for fluid are specified. A state in which a part of the outer peripheral portion of the heat transfer tube and a part of the outer peripheral portion of the fluid heat transfer tube are brought into contact with each other, and the heat exchanger for hot water supply and the heat exchanger for fluid are thermally conducted to each other. Are formed integrally with each other. And a single heating state in which a fluid (water or a fluid to be heated) is supplied only to one of the hot water supply heat exchanger and the fluid heat exchanger,
During the above-described heat retention control process, the heat of the hot water in the hot water supply heat exchanger is transferred to the fluid to be heated in the heat exchanger for fluid, and conversely, the heat of the fluid to be heated in the heat exchanger for fluid is By conducting heat to the hot water in the hot water supply heat exchanger,
It is possible to prevent the fluid to be heated in the fluid heat exchanger and the hot water in the hot water supply heat exchanger from boiling.

According to the seventh aspect of the present invention, the fluid to be heated is circulated between the heat exchanger for fluid and a heat consuming terminal or the fluid to be heated on the outgoing path is supplied to the inflow path. Fluid circulating means for circulating in a fluid circulating circuit including a heating target fluid bypass path is provided, and the control means is configured to operate the fluid circulating means during execution of the heat retention control process. .

That is, the control means is configured to operate the fluid circulation means during the execution of the heat retention control processing. Therefore, during the execution of the heat retention control processing, the control unit causes the fluid to be heated on the outgoing path to enter the inflow path. Fluid in the fluid circulation circuit including the bypass path for the fluid to be heated to be supplied to the heater, so that the temperature of the hot water in the hot water supply heat exchanger can be evenly raised to an appropriate temperature, or the fluid circulation circuit including the fluid heat exchanger and the bypass path It is possible to keep the whole of the fluid to be heated circulating in the inside.

According to the eighth aspect of the present invention, a hot water supply temperature detecting means for detecting a temperature of hot water in the hot water supply heat exchanger and a temperature of a fluid to be heated in the fluid heat exchanger are detected. A fluid temperature detecting means for controlling the temperature of the hot water supply or the temperature detected by the fluid temperature detecting means during the heat retention control process. When the temperature is equal to or higher than a set temperature, the combustion of the burner is stopped.

That is, if the control means detects that the temperature detected by the hot water supply temperature detection means or the temperature detected by the fluid temperature detection means becomes higher than the set temperature for preventing boiling during the heat retention control processing, the burner combustion is stopped. Since the configuration is such that the temperature of the hot water in the hot water supply heat exchanger rises excessively or the temperature of the fluid to be heated in the fluid heat exchanger becomes excessive during execution of the heat retention control process. , The burner combustion can be stopped. Therefore, it is possible to keep the hot water in the hot water supply heat exchanger and the hot water in the fluid heat exchanger while preventing the boiling water in the hot water supply heat exchanger and the fluid to be heated in the fluid heat exchanger from boiling. It becomes possible.

According to the ninth aspect of the present invention, there is provided a bypass which supplies the water supplied through the water supply passage to the hot water supply passage bypassing the hot water supply heat exchanger. The hot water and the water from the bypass are mixed by heating the hot water in the vessel, and the hot water is supplied through the hot water supply path.

That is, a part of the water supplied through the water supply path is supplied to the hot water supply heat exchanger, and the remaining part is supplied to the bypass path. After mixing with the water from the channel, hot water can be supplied through the hot water channel, so that the total amount of water supplied through the water channel is supplied to the hot water heat exchanger. Water flow to the exchanger can be reduced,
By increasing the temperature of hot water inside the hot water supply heat exchanger, dew condensation of the hot water supply heat exchanger can be prevented, and the durability of the hot water supply heat exchanger can be improved.

According to the tenth aspect of the present invention, the control means is configured to, when the freeze prevention start condition is satisfied, determine that the heat retention start condition is satisfied. That is, when the freeze prevention start condition is satisfied, the control means determines that the heat retention start condition is satisfied, and can start burning the burner. It is possible to prevent freezing of water in a water supply channel or a hot water supply channel without providing a freezing prevention heater or the like for preventing the water supply. Freezing can be prevented.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hot water supply apparatus according to the present invention will be described with reference to the drawings. [First Embodiment] As shown in FIGS. 1 and 2, this hot water supply apparatus heats water supplied through a water supply passage 1 by burning a burner 2 and supplies hot water to a hot water supply passage 3. The heat medium supplied through the heating return path 5 is supplied to the burner 2
The fluid heat exchanger 7, which is heated by the combustion of the fluid and flows out to the high-temperature heating path 6, the liquid heat exchanger 35 for exchanging heat between the heat medium heated by the fluid heat exchanger 7 and the bathtub hot water. And a control unit H for controlling the operation, the burner 2, the hot water supply heat exchanger 4, the fluid heat exchanger 7, etc.
It is provided within.

The hot water supply heat exchanger 4 is connected at its inlet side to a water supply path 1 connected to a water pipe and at its outlet side to a hot water supply path 3 connected to a hot water tap (not shown). The water supplied through the water supply channel 1 is heated by the combustion of the burner 2 and supplied to the hot water supply channel 3 to perform general hot water supply or hot water filling.

The water supply channel 1 is provided with a water filter 8, a water supply thermistor 9 for detecting water supply temperature, and a water amount sensor 10 for detecting water supply amount in order from the upstream side. A bypass path 11 for bypassing the exchanger 4 and supplying the hot water path 3 is provided.
Is connected to the hot water supply path 3 by branching a downstream side of the water flow sensor 10 in the water supply path 1.

The hot water supply path 3 includes, in order from the upstream side, a hot water supply thermistor 12 for detecting the temperature of hot water from the hot water supply heat exchanger 4, a hot water supply from the hot water supply heat exchanger 4 and a bypass path 11.
Mixing valve 13, which adjusts the mixing ratio with water from
A mixing thermistor 14 for detecting the temperature of the hot and cold water after being mixed by the mixing valve 13; a water proportional valve 15 for adjusting the amount of hot and cold water supplied through the hot water supply passage 3; A pressure prevention device 17 is provided. The mixing valve 13 is provided at a connection portion between the bypass path 11 and the hot water supply path 3. In the hot water supply path 3, a mixing section 18 between the water proportional valve 15 and the interrupted water amount sensor 16 connects a hot water filling path 18 for bath. It has branched.

That is, a part of the water supplied through the water supply channel 1 is supplied to the hot water supply heat exchanger 4, and the remaining part is supplied to the bypass path 11, and is heated by the hot water supply heat exchanger 4. After mixing hot and cold water and water from the bypass path 11, the hot water is supplied through the hot water supply path 3.

The fluid heat exchanger 7 is connected at its inlet side to the heating return path 5 as an inlet, at its outlet side to the high-temperature heating outgoing path 6 as an outlet, and supplied through the heating return path 5. The heating medium is heated by the combustion of the burner 2, flows out to the high-temperature heating outgoing passage 6, and supplies the heating medium to the heating terminal D as a heat consuming terminal.

In the heating return path 5, in order from the upstream side,
A heating return thermistor 19, a makeup water tank 20, and a heating pump 21 as a fluid circulation means are provided, and a heating outgoing high temperature thermistor 22 is provided in the high temperature heating outgoing passage 6 near the fluid heat exchanger 7. . In the heating return path 5, from a portion downstream of the heating pump 21,
A low-temperature heating path 23 that supplies a heat medium to a low-temperature heating terminal D2 (for example, a floor heating device) is branched, and the low-temperature heating path 23 is provided with a heating low-temperature thermistor 24. In addition, a heating bypass path 6a is provided as a heating target fluid bypass path that supplies the heat medium in the high-temperature heating outgoing path 6 to the heating return path 5 by bypassing the high-temperature heating terminal D1 (for example, an indoor heating device), The heating bypass 6a
Is connected upstream of the heating return thermistor 19 in the heating return path 5.

The make-up water tank 20 is connected to a make-up water passage 25 branched from a location between the water filter 8 and the water supply thermistor 9 in the water supply passage 1, and is connected to an overflow passage 26. Is provided with a makeup water valve 27 and a makeup water solenoid valve 28. The makeup water tank 20 is provided with an upper limit sensor 29 for detecting the upper limit of the water level and a lower limit sensor 30 for detecting the lower limit of the water level. The lower limit sensor 30 detects that the water level of the makeup water tank 20 is at the lower limit. Then, until the upper limit sensor 29 detects that the water level in the makeup water tank 20 is at the upper limit, the opening and closing of the makeup water solenoid valve 28 is controlled so that water is supplied to the makeup water tank 20 through the makeup water channel 25. It is configured to be.

A high-temperature heating terminal D 1 is connected to the high-temperature heating outgoing path 6 and the heating return path 5.
A low-temperature heating terminal D2 is connected to 3 and the heating return path 5, and a heat-consuming terminal is constituted by a high-temperature heating terminal D1 and a low-temperature heating terminal D2. And the heating pump 21
, The hot and cold water in the makeup water tank 20 flows through the heating return path 5, and a part of the hot water flows around the fluid heat exchanger 7 and passes through the low-temperature heating outgoing path 23, and the low-temperature heating terminal D 2.
And the remainder flows into the heat exchanger for fluid 7, and the hot water heated by the heat exchanger 7 for fluid is supplied to the high-temperature heating terminal D1 through the high-temperature heating outgoing path 6, and from the high-temperature heating terminal D1. Both the returning hot water and the hot water returning from the low-temperature type heating terminal D2 are returned to the makeup water tank 20 through the heating return path 5.

A bath adapter A provided in the bathtub A is connected to a bath return path portion 32 and a bath going path portion 33, and the bath pump 3 provided in the bath return path portion 32 is connected to the bath pump A.
By operating the bath 4, the bathtub hot and cold water is supplied to the bath circulation path 36 including the bath return path section 32 and the bath going path section 33.
It is configured to circulate through. Further, a bath pump 34 is provided as a bath circulation means, and the liquid heat exchange between the heat medium heated by the fluid heat exchanger 7 and the bath tub circulated by the operation of the bath pump 34 is performed. An exchanger 35 is provided.

The liquid-to-liquid heat exchanger 35 has a bath heating outgoing passage 37 branched from the high temperature heating outgoing passage 6 and a bath circulation passage 3.
6 has a concentric double-pipe structure with a bath heating outgoing passage 37 inside and a bath circulation passage 36 outside in some sections. The liquid-to-liquid heat exchanger 35 is configured such that the flow direction of the heat medium in the bath heating outgoing passage 37 and the flow direction of the bathtub hot water in the bath circulation passage 36 are opposite to each other.

That is, the fluid heat exchanger 7 uses the high-temperature heating terminal D1 or the low-temperature heating terminal D2 as the fluid to be heated.
Is supplied through the heating return path 5 to heat the heat medium supplied to the high-temperature heating terminal D1 and the low-temperature heating terminal D2 through the high-temperature heating outgoing path 6 and the low-temperature heating outgoing path 23. A bath pump 34 and a bath circulation path 36 circulating through the return path part 32 and the bath going path part 33 are provided, and the heat medium heated by the fluid heat exchanger 7 and the bath pump 34 and the bath circulation path 36
A liquid-to-liquid heat exchanger 35 for exchanging heat with the bathtub hot and cold water circulated by the heat exchanger is provided.

In the bath heating path 37, a bath heat valve 38 is provided upstream of the liquid heat exchanger 35 in the flow direction of the heat medium, and the bath heat valve 38 is opened and closed. By doing so, it is configured to switch between a state in which the heat medium heated by the fluid heat exchanger 7 is supplied to the liquid-liquid heat exchanger 35 and a state in which the heat medium is not supplied.

In the bath return path portion 32, in order from the upstream side, that is, from the circulation adapter 31 side, the bath return path portion 3
2, a pressure detection type water level sensor 39 for detecting the water level in the bathtub A based on the pressure acting on the bath 2, and the bath return thermistor 4.
A bath two-way valve 41 for opening and closing the bath return path portion 32, a bath pump 34, and a water flow switch 42 are provided. The bath going path portion 33 is provided with a bath going thermistor 43.

The hot water supply path 18 for supplying bath water from the hot water supply path 3 to the bathtub A is provided with a bath return path portion 32.
, A bath breaker 44, a pouring solenoid valve 45 that opens and closes the hot water path 18 are connected to the hot water path 18 in this order from the upstream side, A hot water check valve 46 is provided.

Then, the hot water from the hot water supply heat exchanger 4 is
After mixing with water from the bypass path 11 by the mixing valve 13, the hot water is supplied to the bath tub A through the hot water supply path 3, the hot water filling path 18, the bath return path part 32 and the bath going path part 33 to fill the bath. It is configured as follows. By operating the bath pump 34, the bath tub water is circulated between the liquid heat exchanger 35 and the bath tub A through the bath return path portion 32 and the bath flow path portion 33, and the bath flow heat valve 38 is provided. Is opened and the heating pump 21 is operated, so that the heat medium heated by the fluid heat exchanger 7 is passed through the bath heating outgoing passage 37 to the liquid-liquid heat exchanger 3.
By supplying the water to the bath 5, the bath tub hot water is heated by the heat medium in the bath heating outward path 37, and the bath tub hot water is additionally fired.

The burner 2, as shown in FIGS.
It is a multi-stage gas burner, in which the direction of formation of the flame is directed downward, the hot water supply heat exchanger 4 and the fluid heat exchanger 7 share a single burner 2, and the burner 2 is provided in a burner case 47. And the hot water supply heat exchanger 4 and the fluid heat exchanger 7
Is disposed downstream of the burner 2 in the flow direction of the combustion exhaust gas of the burner 2, that is, below the burner 2. A fan 48 for supplying combustion air to the burner 2
In the vicinity of the burner 2, an igniter 53 for igniting the burner 2, a frame rod 54 for detecting ignition of the burner 2, and the like are provided.

A gas supply path 49 for supplying general household fuel gas to the burner 2 is branched into three systems and connected to the burner 2, and a gas switching electromagnetic valve 50 is provided at each gas supply path branch part 49a. Have been. Then, in the gas supply path 49 on the upstream side of the branch point, in order from the upstream side,
An original gas solenoid valve 52 for interrupting the supply of fuel gas and an electromagnetic gas proportional valve 51 for adjusting the fuel gas supply amount are provided.

The hot water supply heat exchanger 4 comprises a hot water supply sensible heat exchange section 4a for recovering the sensible heat of the combustion exhaust gas of the burner 2, and a heat exchange section 4a for the combustion exhaust gas of the burner 2 more than the hot water supply sensible heat exchange section 4a. A hot water supply latent heat exchange unit 4b disposed downstream of the flow direction and recovering latent heat of the combustion exhaust gas from the burner 2 is provided. The fluid heat exchanger 7 includes a fluid sensible heat exchange section 7a as a fluid sensible heat exchange section for recovering the sensible heat of the combustion exhaust gas from the burner 2, and a fluid sensible heat exchange section 7
and a fluid latent heat exchange section 7b as a fluid latent heat exchange section disposed downstream of the burner 2 in the flow direction of the combustion exhaust gas of the burner 2 and recovering latent heat of the combustion exhaust gas of the burner 2. ing.

The hot water supply sensible heat exchange section 4a and the fluid sensible heat exchange section 7a are integrally formed so as to conduct heat to each other, and the hot water supply latent heat exchange section 4b and the fluid latent heat exchange section The heat exchange part 7b is integrally formed with the heat exchange part 7b in a state of conducting heat mutually. Further, the hot water supply heat exchanger 4 and the fluid heat exchanger 7 are arranged downstream of the burner 2 in the flow direction of the combustion exhaust gas from the burner.

More specifically, the burner 2 is provided in the burner case 47 so that the flame formation direction is downward.
The combustion exhaust gas of the burner 2 is configured to flow downward. A sensible heat exchange unit K is provided below the burner 2 in which the hot water supply sensible heat exchange unit 4a and the fluid sensible heat exchange unit 7a are integrally formed in a state of conducting heat to each other. Below the sensible heat exchange section K, there is provided a latent heat exchange section N in which the hot water supply latent heat exchange section 4b and the fluid latent heat exchange section 7b are integrally formed in a state of conducting heat to each other.

Further, condensed water, that is, drain, which drops from the hot water supply latent heat exchange unit 4b and the fluid latent heat exchange unit 7b is provided below the hot water supply latent heat exchange unit 4b and the fluid latent heat exchange unit 7b. A drain recovery path 55 for recovery is provided, and the drain recovered in the drain recovery path 55 is supplied to a neutralization device 56 to neutralize the drain and then discharge the same. As the neutralizing device 56, for example, various neutralizing devices such as a device that neutralizes with a metal having a high ionization tendency such as Mg or Zn are applicable.

The sensible heat exchange section K will be described in further detail. As shown in FIGS. 2, 3 and 5, a hot water supply heat transfer pipe 57 for passing water from the water supply passage 1 and a high-temperature type heating terminal D1 are provided. A heating heat transfer tube 58 as a fluid heat transfer tube through which a heat medium such as from the above passes is provided so as to penetrate a plurality of sensible heat transfer fins 59 in the longitudinal direction. And, on both lateral sides of the sensible heat exchange section K, the hot water supply heat transfer tubes 57
And a U-shaped heat transfer tube 60 is connected so that the heat transfer tube 58 for heating is U-shaped, and the heat transfer tube 57 for hot water supply and the heat transfer tube 58 for heating include a plurality of heat transfer tubes for sensible heat. The pipe is formed so as to meander while penetrating the fins 59. Further, the heat transfer fins 59 for sensible heat are provided with through holes 61 for inserting the heat transfer tubes 57 and the heat transfer tubes 58, as shown in FIG. The heat transfer tube 57 and the heating heat transfer tube 58 are configured to fit inside the through holes 61 of the sensible heat transfer fins 59.

More specifically, in order for the heat transfer pipe 57 and the heat transfer pipe 58 to conduct heat to each other, a part of the outer circumference of the heat transfer pipe 57 and a portion of the outer circumference of the heat transfer pipe 58 are connected. There is provided a sensible heat integrated portion 62 configured to be brought into contact with the portion, and a sensible heat single portion 63 configured only from the hot water supply heat transfer tube 57. The sensible heat transfer fins 59 have an integrated sensible heat through hole 64 for inserting the sensible heat integrated portion 62, and a sensible heat singular type through hole for inserting the sensible heat single portion 63. A hole 65 is provided. In the upper part of the sensible heat transfer fins 59, five integrated sensible heat through-holes 64 are provided in a row in the horizontal direction. The four mold through-holes 65 are provided in a state of being arranged in the lateral direction.

The sensible heat exchange section K is a sensible heat
2 is fitted in the sensible heat integrated through-hole 64, and the sensible heat singular portion 63 is fitted in the sensible heat single-type through hole 65.

As shown in FIGS. 2, 3 and 6, the latent heat exchange section N includes a hot water supply heat transfer pipe 57 for passing water from the water supply passage 1 and a heat medium from the high temperature type heating terminal D1 or the like. Is provided so as to penetrate a plurality of latent heat transfer fins 66 in the longitudinal direction thereof. Then, on both lateral sides of the latent heat exchange section N, a U-shaped heat transfer tube 67 is connected so that the hot water supply heat transfer tube 57 and the heating heat transfer tube 58 are U-shaped. The heat transfer tube 57 and the heat transfer tube 58 for heating are arranged in a meandering manner so as to penetrate the plurality of heat transfer fins 66 for latent heat. In addition, the latent heat transfer fins 66 include:
As shown in (b) of FIG. 7, the hot water supply tube 57 and the heating heat transfer tube 58 are provided with through holes 68 through which the hot water supply heat transfer tube 57 and the heating heat transfer tube 58 are inserted.
Are fitted inside the through holes 68 of the latent heat transfer fins 66 with the heat transfer cover P fitted outside.

More specifically, in order for the heat transfer pipe 57 and the heating pipe 58 to conduct heat to each other, a part of the outer circumference of the heat transfer pipe 57 and a part of the outer circumference of the heating pipe 58 are connected. There is provided a latent heat integral portion 69 configured to make contact with the portion, and a latent heat singular portion 70 configured solely from the hot water supply heat transfer tube 57. The heat transfer cover P is provided with a latent heat integrated heat transfer cover P1 externally fitted to the latent heat integrated portion 69 and a latent heat single heat transfer cover P2 externally fitted to the latent heat single portion 70. ing.

The latent heat transfer fin 66 is provided with an integrated latent heat through hole 7 through which the latent heat integrated portion 69 is inserted.
1 and a latent heat singular type through hole 72 through which the latent heat singular portion 70 is inserted. The latent heat transfer fins 66 are provided with four integrated latent heat through holes 71 arranged in the horizontal direction at the upper portion thereof. Are provided so as to be arranged side by side in the horizontal direction, and at the lower portion thereof, single-side latent heat-use holes 72 are provided so as to be arranged side by side in the horizontal direction.

The latent heat exchanging section N includes an integral part 6 for latent heat.
9 is fitted inside the latent heat integral type through-hole 71 with the latent heat integral heat transfer cover P1 fitted externally, and the latent heat singular portion 70 is fitted externally to the latent heat single heat transfer cover P2. In this state, it is configured to be fitted inside the single-type latent heat through hole 72.

Further, a hot water supply boiling prevention thermistor 100 as a hot water supply temperature detecting means for detecting a temperature of hot water in the hot water supply heat exchanger 4 and a temperature of a heat medium in the fluid heat exchanger 7 are detected. A heat medium boiling prevention thermistor 101 as a fluid temperature detecting means is provided. That is, the hot water supply boiling prevention thermistor 100 is provided on the U-shaped heat transfer tube 60 that connects the hot water supply heat transfer tube 57 in the sensible heat exchange section K, and the heat medium boiling prevention thermistor 10 is provided.
1 is provided on a U-shaped heat transfer tube 60 that connects the heating heat transfer tube 58 in the sensible heat exchange section K.

As shown in FIG. 4, the burner 2 includes a rich burner 2a for burning a rich air-fuel mixture having a small air mixing ratio and a light burner 2b for burning a light air-fuel mixture having a high air mixing ratio. , Multiple burners 2a and light burners 2b
Are alternately juxtaposed with the width direction thereof being juxtaposed, and the box-shaped frame 2c provided in the burner case 47 is provided.
Is housed inside. Then, the lean air-fuel mixture of the light burner 2b is burned while maintaining the flame by the rich flame generated in the rich burner 2a, so that the fuel gas is burned at a large air mixing ratio as a whole, and the generation of NOx as nitrogen oxides is reduced. It is configured so that stable combustion can be performed while suppressing it as much as possible.

Further, this burn-in-concentration burner is a burner 2
The latent heat of the combustion exhaust gas of the burner 2 is recovered by setting the air ratio of the entire lean burner as low as possible by, for example, increasing the amount of fuel gas supplied to the lean burner 2b as much as the amount of combustion gas supplied to the burner 2a. The configuration is such that the burner 2 is burned in an easy-to-operate state, and the latent heat of the combustion exhaust gas can be efficiently recovered in the latent heat exchange section N.

A kitchen remote controller 73 and a bathroom remote controller 74 for giving various instructions to the controller H are provided. The controller H is controlled by the kitchen remote controller 73 and the bathroom remote controller 74 as shown in FIG. , Burner operating part B,
The hot water supply operation unit X, the bath operation unit Y, and the heating operation unit Z are controlled to perform various operations such as a general hot water supply operation, an automatic bath operation, a hot operation, and a heating operation. In a state where the supply of water is stopped and the supply of the heat medium to the fluid heat exchanger 7 is stopped, when the condition for starting the heat retention is satisfied, the heat retention control process for starting the combustion of the burner 2 and keeping the temperature is executed. It is configured to be.

Incidentally, the burner operating section B is provided with the fan 4
8, a gas switching solenoid valve 50, a gas proportional valve 51, a source gas solenoid valve 52, an igniter 53, a frame rod 54, and the like. The hot water supply operation unit X includes a water supply thermistor 9, a water amount sensor 10, a hot water supply thermistor 12, and a mixing valve. 1
3. The mixing thermistor 14 and the like. The bath operation unit Y includes a bath pump 34, a water level sensor 39, a bath return thermistor 40, a bath two-way valve 41, a water flow switch 42, a bath going thermistor 43, a pouring solenoid valve 45, and the like. Is composed of a heating return thermistor 19, a heating pump 21, a heating high temperature thermistor 22, a heating low temperature thermistor 24, and the like.

The kitchen remote controller 73 has an operation switch 75 for instructing a general hot water supply operation executable state, a hot water temperature setting section 76 for setting a hot water supply temperature, an automatic bath switch 77 for instructing automatic bath operation, and a heating operation. There are provided a heating switch 78 for instructing, a hot water supply / insulation switch 83 for selecting whether or not to execute the heat retention control processing, and the like. The bathroom remote control 74 has an operation switch 79 for instructing a general hot water supply operation executable state, a bath setting change switch 80 for setting a hot water temperature and a water level to the bathtub A, and a bath automatic switch for instructing bath automatic operation. A hot switch 81 for instructing a hot operation is provided.

The operation of the control section H in various operations will be described. The general hot water supply operation is performed by the kitchen remote control 7.
In a state where the operation switch 75 of the third embodiment or the operation switch 79 of the bathroom remote controller 74 is ON, if the water amount detected by the water amount sensor 10 becomes equal to or more than a predetermined amount due to the opening operation of the hot water tap or the like, the fan 48 is driven. The gas switching solenoid valve 50 is appropriately switched to open the original gas solenoid valve 52,
The opening of the gas proportional valve 51 is adjusted, and the burner 2 is ignited by the igniter 53. When the burner 2 is ignited, the temperature set by the hot water supply temperature setting unit 76 of the kitchen remote controller 73, the detected water temperature by the water supply thermistor 9, and the water amount sensor 1
The gas switching solenoid valve 5
0 is switched, the opening of the gas proportional valve 51 is adjusted, and the opening of the mixing valve 13 is also adjusted, so-called feedforward control is performed so that the hot water supply temperature becomes the set temperature. The hot and cold water heated by the exchanger 4 and the water from the bypass passage 11 are mixed to supply hot and cold water at a set temperature through the hot water supply passage 3.

In addition to the feedforward control, the degree of opening of the gas proportional valve 51 is finely adjusted based on the difference between the temperature set by the hot water temperature setting unit 76 of the kitchen remote controller 73 and the detected hot water temperature by the mixing thermistor 14. The so-called feedback control is executed to supply hot water at the temperature set by the hot water temperature setting unit 76 of the kitchen remote controller 73 to the hot water tap. When the water amount sensor 10 stops detecting a predetermined amount of water flow with the closing operation of the hot water tap, the original gas solenoid valve 52 and the gas proportional valve 51 are closed to stop the combustion of the burner 2, and the combustion is stopped. After the lapse of time, the fan 48 is also stopped to end the general hot water supply operation.

When the bath automatic switch 77 of the kitchen remote controller 73 or the bath automatic switch 81 of the bathroom remote controller 74 is turned on, the pouring solenoid valve 45 is opened and the water level sensor 10 is turned on by a predetermined amount or more. Is detected, the burner 2 is ignited in the same manner as in the general hot water supply operation described above,
Hot water at a set temperature is supplied to the bathtub A by the feedforward control and the feedback control. That is, the opening degree of the gas proportional valve 51 and the mixing valve 13 is adjusted, the water from the water supply passage 1 is heated by the hot water supply heat exchanger 4, and the heated hot water is mixed with the water from the bypass passage 11. Then, hot water of the set temperature is supplied to the bath return path portion 32 and the bath going path portion 33 via the hot water path 18, and is supplied into the bathtub A from both the bath return path portion 32 and the bath going path portion 33. You.

When a predetermined amount of hot water is supplied to the bathtub A, the bath pump 34 is operated to close the bath two-way valve 41, and the water level sensor 39 detects the water level in the bathtub A. When the set water level is reached, the pouring solenoid valve 45
Is closed, the original gas solenoid valve 52 and the gas proportional valve 51 are closed to stop the burner 2 from burning, and the fan 48 is also stopped after a certain period of time. In this way, the water level of the bathtub A is appropriately detected, and hot water is supplied to the bathtub A so that the water level of the bathtub A becomes the set water level. When hot water of the set water level is supplied to the bathtub A, the bath pump 34 is operated to perform a hot operation described later so that the temperature of the hot water of the bathtub becomes the set temperature. If the hot water tap is opened during the hot water filling operation, the interruption water amount sensor 16 detects the water flow, stops the bath automatic operation, and executes the general hot water supply operation. That is,
The general hot water supply operation is executed with priority, and when the hot water tap is closed, the bath automatic operation is restarted.

The hot operation is performed when the hot switch 82 of the bathroom remote controller 74 is turned ON.
Operates, the bathtub hot water is circulated through the bath circulation path 36 as shown by the solid arrow in FIG. 1, the water flow switch 42 is turned on, and the bathtub hot water is supplied to the liquid-liquid heat exchanger 35.
When the water flow switch 42 is turned on, the burner 2 is ignited, and the gas switching solenoid valve 50 is switched so that the burned amount of the burner 2 becomes an operating combustion amount, and the gas proportional valve 51 is opened. The degree is adjusted. Further, with the turning on of the water flow switch 42, the heating pump 21 is operated to open the bath heat-operated valve 38, and as shown by the dotted arrow in FIG. The heated heat medium is supplied to the liquid-liquid heat exchanger 4.

As described above, in the liquid-liquid heat exchanger 35, the bath tub water is heated by the heat medium heated by the fluid heat exchanger 7, and the detected temperature of the bath return thermistor 40 becomes slightly lower than the set temperature. When the temperature becomes high, the original gas solenoid valve 52
Then, the combustion of the burner 2 is stopped by closing the gas proportional valve 51, and the fan 48 is also stopped after a predetermined time has elapsed. Then, the bath outgoing thermal valve 38 is closed to stop the heating pump 21, the bath two-way valve 41 is closed, and the bath pump 34 is stopped to end the hot operation. Even if the hot switch 82 is turned off, the above-described operation is performed, and the hot operation ends.

The heating operation includes a high-temperature heating operation for circulating a heat medium to the high-temperature heating terminal D1 and a low-temperature heating terminal D1.
2 is a low-temperature heating operation for circulating and supplying a heat medium. In the high-temperature heating operation, when there is an operation command from the heating remote controller or when the heating switch 78 of the kitchen remote controller 73 is turned on, the heating pump 21 is operated, the burner 2 is ignited, and the high-temperature heating terminal D1 is turned on. Burner 2 depending on load
Is controlled proportionally or ON / OFF controlled. That is, in the proportional control, the gas switching solenoid valve 50 is switched based on the detected temperature of the high-temperature thermistor 22 for heating and the opening degree of the gas proportional valve 51 is adjusted, so that the combustion amount of the burner 2 is reduced to the maximum combustion amount and the minimum combustion amount. The ON / OFF control is switched between a state in which the burner 2 burns with the minimum combustion amount and a state in which the burner 2 stops burning.

In the low-temperature heating operation, when there is an operation command from the heating remote controller, the heating pump 21 is operated, the burner 2 is ignited, and the low-temperature heating terminal D2 is operated in accordance with the load.
The combustion state of the burner 2 is proportionally controlled or ON / OFF controlled. That is, in the proportional control, the gas switching solenoid valve 50 is switched based on the detected temperature of the low-temperature thermistor 24 for heating and the opening degree of the gas proportional valve 51 is adjusted to reduce the combustion amount of the burner 2 to the maximum combustion amount and the minimum combustion amount. The ON / OFF control is switched between a state in which the burner 2 burns with the minimum combustion amount and a state in which the burner 2 stops burning.

Various operations can be simultaneously performed by controlling the combustion amount of the burner 2, such as a general hot water supply operation and a heating operation, and a general hot water supply operation and a bath automatic operation. For example, if there is a request for the heating operation during the general hot water supply operation, the general hot water supply operation and the heating operation are performed simultaneously by adding the combustion amount according to the load of the heating terminal D to the current combustion amount of the burner 2. It becomes possible. By the way, when performing a plurality of operations at the same time, it is set in advance which operation conditions are prioritized based on various conditions, and each operation is performed based on the set priority conditions. It is configured.

The control unit H supplies the heat medium to the fluid heat exchanger 7 and stops the supply of water to the hot water supply heat exchanger 4 by performing the heating operation and the hot operation independently. In the fluid-only heating state, when the hot-water supply boiling prevention condition is satisfied, for example, when the temperature detected by the hot-water supply boiling prevention thermistor 100 becomes equal to or higher than the set temperature for boiling, the accumulator provided in the water supply passage 1 (see FIG. (Not shown), and the pouring solenoid valve 46 and the bath two-way valve 41 are opened, and the bath pump 34 and the like are operated so that the water in the heat exchanger 4 for hot water supply flows into the bathtub A. The boiling water in the hot water supply heat exchanger 4 is prevented from boiling.

Incidentally, the prevention of boiling of the hot water in the hot water supply heat exchanger 4 and the heat medium in the fluid heat exchanger 7 is described below.
Basically, in the sensible heat exchange section K and the latent heat exchange section N, a portion of the outer peripheral portion of the hot water supply heat transfer tube 57 and a portion of the outer peripheral portion of the heating heat transfer tube 58 are brought into contact with each other to supply hot water. Between the hot water in the heat exchanger 4 for water and the heat medium in the heat exchanger 7 for fluid, and the fluid (water or heat medium) in the heat exchanger 4 for hot water supply and the heat exchanger 7 for fluid. ) Is suppressed so that the temperature of the fluid on the side where the supply of the fluid is stopped is prevented, and the fluid (water or heat medium) is prevented from boiling.

The heat keeping control process by the control unit H will be described. This heat retention control process is executed when the hot water supply / heat retention switch 83 of the kitchen remote controller 73 is turned ON.
It is configured not to be executed when the hot water supply warming switch 83 is turned OFF, and when the warming start condition is satisfied,
The combustion of the burner 2 is started to keep the hot water in the hot water supply heat exchanger 4 at the target set temperature.

More specifically, in a state where the supply of water to the heat exchanger 4 for hot water supply is stopped and the supply of the heat medium to the heat exchanger 7 for fluid is stopped, the thermistor for hot water supply boiling prevention is provided. When the temperature Tk detected by the control unit 100 becomes equal to or lower than the combustion start set temperature, it is determined that the heat retention start condition is satisfied, and the burner 2 starts combustion, and the hot water supply boiling prevention thermistor 1 is started.
When the detected temperature Tk of 00 becomes equal to or higher than the combustion stop set temperature, it is determined that the heat retention stop condition is satisfied, the combustion of the burner 2 is stopped, and the hot water in the hot water supply heat exchanger 4 is maintained at the target set temperature. Is configured.

Incidentally, a temperature lower by the set amount α than the set target temperature Ts of the hot water heated by the hot water supply heat exchanger 4 is set as a combustion start set temperature, and a temperature higher by the set amount β than the set target temperature Ts. Is set as the combustion stoppage setting temperature, and the set target temperature Ts is changed and set based on the hot water supply setting temperature set by the hot water supply temperature setting section 76 of the kitchen remote controller 73. The hot water supply temperature setting unit 76 of the kitchen remote controller 73 is configured to change and set the temperature based on the hot water supply set temperature. The set amounts α and β are appropriately set according to the characteristics of the water heater, and may be different values or may be set to the same value.

Further, the control unit H stops the combustion of the burner 2 when the heat retention stop condition is satisfied during the heat retention control process. However, even if the heat retention stop condition is not satisfied, the control unit H supplies hot water. Temperature detected by the boiling prevention thermistor 100 or the boiling prevention thermistor 10 for the heat medium
When any one of the temperatures detected by the temperature control unit 1 becomes equal to or higher than the set temperature for preventing boiling, the combustion of the burner 2 is stopped, and the hot water in the hot water supply heat exchanger 4 and the heat medium in the fluid heat exchanger 7 boil. It is configured to prevent Incidentally, the boiling prevention set temperature Tf is the combustion stop set temperature Ts.
Even if a temperature higher than + β is set and the heat retention stop condition is not satisfied, the boiling preventive thermistor 101 for the heat medium is used.
When the detected temperature Tn is equal to or higher than the set temperature Tf for preventing boiling, the combustion of the burner 2 is stopped.

In this way, while preventing the boiling water in the hot water supply heat exchanger 4 and the heat medium in the fluid heat exchanger 7 from boiling, the hot water in the hot water supply heat exchanger 4 is kept at the target set temperature. Then, from the beginning of hot water supply, let the hot water of the desired temperature be supplied,
It is possible to meet the demand for supplying hot water at a desired temperature from the start of hot water supply, and to improve the usability of the apparatus.

The control operation of the control section H in the heat retention control processing will be described with reference to the flowchart of FIG. When the supply of water to the hot water supply heat exchanger 4 is stopped and the supply of the heat medium to the fluid heat exchanger 7 is stopped, the hot water supply boiling prevention thermistor 10 is stopped.
When the detected temperature Tk due to 0 becomes equal to or lower than the combustion start set temperature Ts-α, the combustion of the burner 2 is started (step 1).
~ 3). Then, the boiling prevention thermistor 101 for the heat medium
If the detected temperature Tn is lower than the set temperature Tf for preventing boiling and the temperature Tk detected by the thermistor 100 for preventing boiling for hot water supply is lower than the set temperature Ts + β for stopping the combustion, the combustion of the burner 2 is continued (step 3). , 4,
5).

During the combustion of the burner 2, even if the temperature Tk detected by the hot water supply boiling prevention thermistor 100 is lower than the combustion stop temperature Ts + β, the temperature Tn detected by the heat medium boiling prevention thermistor 101 is prevented from boiling. When the temperature exceeds the preset temperature Tf, the combustion of the burner 2 is stopped. When the temperature Tk detected by the hot water supply boiling prevention thermistor 100 exceeds the preset combustion stop temperature Ts + β, the combustion of the burner 2 is stopped (steps 4 to 6). ).

Incidentally, the combustion amount of the burner 2 in the heat retention control processing is set to the heat retention combustion amount, and the fuel supply amount and the combustion air supply amount are adjusted so as to become the heat retention combustion amount. Is configured.

[Second Embodiment] The second embodiment shows another embodiment of the configuration of the hot water supply heat exchanger 4 and the fluid heat exchanger 7 in the first embodiment. It will be described based on the following. Incidentally, the other configuration is the same as that of the first embodiment, and the detailed description thereof is omitted.

That is, in the first embodiment, the hot water supply heat exchanger 4 and the fluid heat exchanger 7 are connected to the hot water supply heat transfer pipe 57.
And a part of the outer peripheral portion of the heat transfer pipe 58 for heating is in contact with each other to be integrally formed in a state of conducting heat mutually. However, in the second embodiment, the hot water supply heat exchanger is used. 4 and the heat exchanger 7 for fluid, the heat transfer pipe 57 for heating and the heat transfer pipe 58 for heating, and a part of the inner peripheral part of the larger diameter of the heat transfer pipe 57 for heating and the heat transfer pipe 58 for heating. A part of the outer peripheral portion having the smaller diameter is brought into contact with each other, and is integrally formed in a state of conducting heat mutually.

More specifically, the heat transfer tube 58 for heating is used.
However, as shown in FIG. 12, the heat transfer pipe 57 is configured to have a diameter larger than that of the heat transfer pipe 57, and a part of the inner circumference of the heating heat transfer pipe 58 and a part of the outer circumference of the heat transfer pipe 57. And the heat exchanger 4 for hot water supply and the heat exchanger 7 for fluid are thermally conducted to each other.

To add an explanation, the sensible heat exchange section K is the same as that shown in FIG.
As shown in FIG. 11A and FIG.
7 and a double tube portion of the heat transfer tube 58 for heating and the heat transfer tube 5 for hot water supply.
7 and a single tube portion so as to penetrate a plurality of sensible heat transfer fins 59 in the longitudinal direction thereof.
9 so as to fit inside the through hole 61.

The latent heat exchange section N is also a sensible heat exchange section K.
Similarly, as shown in (b) of FIG. 10, the double pipe portion of the heat transfer pipe 57 and the heating heat pipe 58 and the single pipe portion of the heat transfer pipe 57 alone are connected to the heat transfer cover P. In a state in which the heat transfer fins 66 are externally fitted, the heat transfer fins 66 are configured to be fitted in the through holes 68 of the heat transfer fins 66 for latent heat so as to penetrate the heat transfer fins 66 for latent heat in the longitudinal direction.

Incidentally, the boiling prevention thermistor 1 for hot water supply
Reference numeral 00 denotes a U-shaped heat transfer tube 60 that connects only a single portion of the hot water supply heat transfer tube 57 in the sensible heat heat exchange unit K. The heat medium boiling prevention thermistor 101 includes a sensible heat exchange unit K. And a U-shaped heat transfer tube 60 connecting the double pipe portions of the hot water supply heat transfer tube 57 and the heating heat transfer tube 58.

In the operation of the control section H, various operations such as a general hot water supply operation and a bath automatic operation and a heat retention control process are the same as those in the first embodiment.
Although the description is omitted, since the operation during execution of the heat retention control process is different from that of the first embodiment,
The point will be explained. That is, in the first embodiment, when the heat retention control process is being performed and the temperature Tn detected by the heat medium boiling prevention thermistor 101 is equal to or higher than the boiling prevention set temperature Tf, the combustion of the burner 2 is stopped. Although it is configured to prevent the heat medium in the fluid heat exchanger 7 from boiling, in the second embodiment, the temperature is detected by the heat medium boiling prevention thermistor 101 during the heat retention control process. Even if Tn is equal to or higher than the set temperature Tf for prevention of boiling, the burner 2 continues to be burned until the condition for stopping heat retention is satisfied, the heat retention control process is being performed, and the detection by the heat medium boiling prevention thermistor 101 is performed. Temperature Tn
When the temperature rises above the boiling prevention set temperature Tf, the heating pump 2
1 is operated to circulate the heat medium in the fluid circulation circuit including the fluid heat exchanger 7 and the heating bypass 6a.

That is, in the second embodiment, the diameter of the heat transfer pipe 57 is larger than that of the heat transfer pipe 57, and a part of the inner circumference of the heat transfer pipe 58 and the outer circumference of the heat transfer pipe 57 are formed. Since the burner 2 has a double-pipe structure in which a part of the heat transfer pipe 58 is brought into contact, the heat medium of the heating heat transfer pipe 58 is heated first, and then the hot water of the hot water supply heat transfer pipe 57 is heated. Therefore, by operating the heating pump 21 to prevent the heat medium in the fluid heat exchanger 7 from boiling,
It is configured to prevent boiling of hot water in the hot water supply heat exchanger 4.

[Other Embodiments] (1) In the first and second embodiments, an example has been shown in which the hot water in the hot water supply heat exchanger 4 is maintained at the target set temperature as the heat retention control process. As a heat retention control process, while keeping the heat medium in the fluid heat exchanger 7 at a target set temperature, the fluid heat exchanger 7 and the heating bypass 6a
The heat medium circulating in the fluid circulation circuit including the above may be configured and implemented so as to keep the entire temperature.

More specifically, the control unit H operates in a state where the supply of water to the heat exchanger 4 for hot water supply and the supply of the heat medium to the heat exchanger 7 for fluid are stopped. When the temperature Tn detected by the boiling prevention thermistor 101 becomes equal to or lower than the fluid combustion start set temperature, it is determined that the heat retention start condition has been satisfied, and the combustion of the burner 2 is started. When the temperature Tn detected by the heat medium boiling prevention thermistor 101 becomes equal to or higher than the set temperature for stopping fluid combustion, it is determined that the heat retention stop condition is satisfied and the combustion of the burner 2 and the heating pump 21 are stopped.
Is stopped to keep the hot and cold water in the fluid heat exchanger 7 at the target set temperature, and the heating pump 21 as a fluid circulating means is activated to operate the fluid heat exchanger 7 and the heating bypass 6a. And circulates in a fluid circulation circuit including the heat transfer medium, and heats the entire heat medium circulated. Incidentally, without operating the heating pump 21, it is also possible to implement and carry out the configuration in which the hot water in the fluid heat exchanger 7 is kept at the target set temperature by the combustion of the burner 2.

As the heat retention control processing, hot water supply priority heat retention processing for keeping the hot water in the hot water supply heat exchanger 4 at the target set temperature, and the heat medium in the fluid heat exchanger 7 at the target set temperature. At the same time, the heating pump 21 is operated,
One of the heat medium priority heat preservation processing for preserving the entire heat medium circulating in the fluid circulation circuit including the fluid heat exchanger 7 and the heating bypass path 6a is performed, and hot water is supplied to the kitchen remote controller 73 and the like. It is also possible to provide a selection switch for selecting whether to execute the preferential heat-retaining process or to execute the heat medium preferential heat-retaining process, and to carry out the selected process.

(2) In the first and second embodiments, the control section H sets the heat retention start condition and the heat retention stop condition based on the temperature as the heat retention control processing, and detects the temperature detected by the hot water supply boiling prevention thermistor 100. Is configured to start or stop the combustion of the burner 2 on the basis of, for example, when the set time for starting the heat retention elapses after the combustion of the burner 2 is stopped, the combustion of the burner 2 is started. It is also possible to set the heat retention start condition and the heat retention stop condition based on the time, such as stopping the combustion of the burner 2 when the heat retention time has elapsed from the start of combustion, and the heat retention start condition and the heat retention stop condition are Change settings can be made as appropriate. Incidentally, the heat retention start condition and the heat retention stop condition may be fixed conditions, or may be corrected from the hot water supply temperature at the start of hot water supply so that hot water of a desired temperature is supplied at the start of hot water supply.

Further, the heat retention control process is not limited to the process of starting the combustion of the burner 2 when the condition for starting the heat retention is satisfied and simply continuing the combustion of the burner 2 until the condition for stopping the heat retention is satisfied. For example, when the heat retention start condition is satisfied, the combustion of the burner 2 is started, and until the heat retention stop condition is satisfied, a state in which the burner 2 is burned and a state in which the combustion of the burner 2 is stopped are repeated at a set cycle. It is also possible to intermittently carry out the combustion of No. 2 and various heat retention control processes are applicable.

(3) In the first embodiment, the control unit H
Although the heating pump 21 is not operated during the execution of the heat retention control process, the control unit H activates the heating pump 21 during the execution of the heat retention control process, so that the heat medium is transferred to the fluid heat exchanger 7.
Circulating in the fluid circulation circuit including the heat bypass passage 6a and the heating medium, thereby preventing the heat medium in the fluid heat exchanger 7 from boiling, and the fluid circulation circuit including the fluid heat exchanger 7 and the heating bypass passage 6a. The heat medium circulating in the inside can be configured and implemented so as to keep the entire temperature.

(4) In the second embodiment, the control unit H
However, the combustion of the burner 2 is configured to continue until the condition for stopping heat retention is satisfied. However, the control unit H is executing the heat retention control process and detects the temperature detected by the heating medium boiling prevention thermistor 101. When Tn becomes equal to or higher than the set temperature Tf for preventing boiling, the combustion of the burner 2 may be stopped even if the heat retention stop condition is not satisfied.

(5) In the first and second embodiments,
The control unit H is configured to execute a heat retention control process for the purpose of keeping the temperature warm. However, when the freeze prevention start condition is satisfied, the control unit H determines that the heat retention start condition is satisfied, and supplies the water supply passage. It is also possible to implement and carry out the heat retention control processing for the purpose of preventing freezing of water in the hot water supply path 1 and the hot water supply path 3 and the like.

To add a further explanation, for example, the control unit H determines that the water supply thermistor 9 has set the freezing prevention start temperature (for example, 4 ° C.).
° C) or less, it is determined that the freezing prevention start condition is satisfied, and the burner 2 is started to burn, and the water supply thermistor 9 is started.
When the temperature exceeds the set temperature for freeze prevention stop, it is determined that the freeze prevention stop condition is satisfied, and the freeze prevention process for stopping the combustion of the burner 2 is executed. In this case, in this case, the control unit H is configured to execute both the heat retention control process for the purpose of keeping the temperature and the freeze prevention process for the purpose of preventing freezing, and the freeze prevention process for the purpose of preventing the freeze. It is also possible to configure to execute only.

(6) In the first and second embodiments,
The control unit H executes the heat retention control process to keep only the hot water in the hot water supply heat exchanger 4, but, for example, as shown in FIG. A circulation bypass path 102 for circulating hot water present in the exchanger 4 and a part of the hot water supply path 3 is provided, and a hot water supply pump 103 is provided in the circulation bypass path 102, and the control unit H During the heat retention control process, the hot water supply pump 1
03 is operated so that not only hot water in the hot water supply heat exchanger 4 but also hot water present in a part of the water supply path 1 and a part of the hot water supply path 3 is kept warm. Is also possible. By the way, in the configuration shown in FIG. 13, when the hot water supply pump 103 is operated, the hot water supply pump 103 is prevented from flowing into the circulation bypass passage 102 and the hot water supply passage 3 when the hot water supply is used. Check valve 104 for preventing gas from flowing into bypass path 11 side
Is provided.

That is, when the control unit H determines that the temperature Tk detected by the hot water supply boiling prevention thermistor 100 becomes equal to or lower than the combustion start set temperature, it is determined that the heat keeping start condition is satisfied.
At the same time as starting the combustion of the burner 2, the hot water supply pump 10
3 is operated, and when the temperature Tk detected by the hot water supply boiling prevention thermistor 100 becomes equal to or higher than the combustion stop set temperature, it is determined that the heat retention stop condition is satisfied, and the combustion of the burner 2 and the operation of the hot water supply pump 103 are stopped. It is configured.

Incidentally, even when the control unit H executes the anti-freezing process as described in the above (5), the hot water supply pump 103 is operated during the anti-freezing process, and the water in the hot water supply heat exchanger 4 is removed. Not only freezing but also freezing of water existing in a part of the water supply path 1 and a part of the hot water supply path 3 can be prevented.

(7) In the first and second embodiments,
Although the flame formation direction of the burner 2 is configured to be downward, it is also possible to configure so that the flame formation direction of the burner 2 is configured to be upward. In this case, the sensible heat exchange section K is located on the lower side, and the latent heat exchange section N is located on the upper side, and the sensible heat exchange section K and the latent heat exchange section in the first embodiment. The arrangement position with the exchange unit N is configured to be turned upside down.

(8) In the first and second embodiments,
A bypass path 11 for supplying water supplied through the water supply path 1 to the hot water supply path 3 bypassing the hot water supply heat exchanger 4 is provided;
Hot water and hot water heated by hot water supply heat exchanger 4 and bypass 11
And hot water is supplied through the hot water supply path 3, but without the bypass path 11, the entire amount of water supplied through the water supply path 1 is supplied to the hot water supply heat exchanger 4. It is also possible to carry out by configuring so as to supply the data.

(9) In the first and second embodiments,
The fluid heat exchanger 7 is configured to heat one fluid as the fluid to be heated. For example, the fluid heat exchanger 7 may use a heat medium supplied to the heating terminal D and a bathtub hot water. It is also possible to configure and carry out heating so that the fluid heat exchanger 7 heats a plurality of fluids.

(10) In the first and second embodiments, in addition to the hot water supply heat exchanger 4 and the fluid heat exchanger 7, the liquid heat exchanger 35 is provided, so that the hot water supply and heating terminal D can be connected. In addition to the supply of the heat medium, it is configured to perform additional heating of the bath water, but it may be configured to perform only the supply of the heat medium to the hot water supply and the heating terminal D, or the hot water supply and the bath water It is also possible to configure and implement such that only additional reheating is performed.

In addition, in the case where only the heating medium is supplied to the hot water supply and the heating terminal, the bath circulation path 36 and the liquid-liquid heat exchanger 35
And so on. In the case where only the hot water supply and the additional heating of the bathtub hot water are performed, the heat medium fluid heat exchanger 7 is connected to the bath circulation path 3 from the bathtub A as an entrance.
6 is supplied through the bath return path portion 32 in the bath circulation path 36 as an outgoing path.
Is configured to heat the bathtub hot water supplied to the bathtub A through the heat exchanger, and the fluid to be heated in the fluid heat exchanger 7 is replaced with the heat medium supplied to the heating terminal D to be the bathtub hot water.

(11) In the first and second embodiments, the hot water supply apparatus according to the present invention is applied to a hot water supply apparatus for supplying hot water, reheating the bathtub hot water, and supplying a heat medium to the heating terminal D. Although an example is shown, the present invention is applicable to various other hot water supply devices.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hot water supply device according to a first embodiment.

FIG. 2 is a schematic front view of the water heater in the first embodiment.

FIG. 3 is a perspective view showing a burner, a sensible heat exchange unit, and a latent heat exchange unit in the first embodiment.

FIG. 4 is a perspective view showing a burner.

FIG. 5 is a side view of the sensible heat exchange unit according to the first embodiment.

FIG. 6 is a side view of the latent heat exchange unit according to the first embodiment.

FIG. 7 is a diagram showing main parts of a sensible heat exchange unit and a latent heat exchange unit in the first embodiment.

FIG. 8 is a control block diagram of a water heater.

FIG. 9 is a flowchart showing a control operation of a heat retention control process.

FIG. 10 is a diagram showing main parts of a hot water supply heat exchanger and a fluid heat exchanger according to a second embodiment.

FIG. 11 is a diagram illustrating a main part of a hot water supply heat exchanger according to a second embodiment.

FIG. 12 is a view showing a relationship between a heat transfer pipe for hot water supply and a heat transfer pipe for fluid in the second embodiment.

FIG. 13 is a schematic configuration diagram of a hot water supply device in another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water supply path 2 Burner 3 Hot water supply path 4 Hot water supply heat exchanger 4a Hot water supply sensible heat exchange section 4b Hot water supply latent heat exchange section 5,32 Incoming path 6,33 Outgoing path 6a Bypass path for fluid to be heated 7 Fluid heat exchange Unit 7a Fluid sensible heat exchange unit 7b Fluid latent heat exchange unit 11 Bypass path 21 Fluid circulating unit 57 Hot water supply heat transfer tube 58 Fluid heat transfer unit 100 Hot water supply temperature detection unit 101 Fluid temperature detection unit D Heat consumption Terminal

Continuation of the front page F term (reference) 3L024 CC01 CC26 DD02 DD13 DD17 DD22 GG05 GG37 HH15 HH26 3L036 AA46

Claims (10)

[Claims] 1. A hot water supply heat exchanger for heating water supplied through a water supply passage by burning a burner to supply hot water to a hot water supply passage, and heating a fluid to be heated supplied through an inlet passage by burning the burner. A heat exchanger for fluid flowing out of the outlet is provided; the heat exchanger for hot water supply and the heat exchanger for fluid are integrally formed in a state of conducting heat to each other; and control for controlling combustion of the burner. A hot water supply apparatus provided with a means, wherein the control means stops supply of water to the heat exchanger for hot water supply and stops supply of a fluid to be heated to the heat exchanger for fluid. In the state, when the heat retention start condition is satisfied, the hot water supply device is configured to execute a heat retention control process of starting combustion of the burner and keeping the temperature. 2. The hot water supply apparatus according to claim 1, wherein the control means is configured to keep the hot water in the hot water supply heat exchanger at a target set temperature as the heat keeping control process. 3. The hot water supply heat exchanger recovers the sensible heat of the combustion exhaust gas of the burner, and the flow of the combustion exhaust gas of the burner is higher than that of the hot water supply sensible heat exchange unit. And a hot water supply latent heat exchange unit that is disposed downstream in the direction and recovers latent heat of the combustion exhaust gas of the burner.The heat exchanger for fluid recovers sensible heat of the combustion exhaust gas of the burner. A sensible heat exchange unit for fluid, and a latent heat heat for fluid disposed downstream of the sensible heat exchange unit for fluid in the direction of flow of the flue gas of the burner to collect latent heat of the flue gas of the burner. An exchange unit is provided.
Or the hot water supply apparatus according to 2. 4. The hot water supply heat exchanger includes a hot water supply heat transfer tube that allows hot water to flow in the hot water supply heat exchanger, and the fluid heat exchanger includes a fluid heat exchanger. A heat transfer pipe for fluid that allows a fluid to be heated to flow therethrough, wherein the heat exchanger for hot water supply and the heat exchanger for fluid are connected to the heat transfer pipe for hot water supply and the heat transfer pipe for fluid, The heat transfer tube for fluid and the heat transfer tube for fluid are formed integrally by contacting a part of the larger diameter inner peripheral part and a part of the smaller diameter outer peripheral part to conduct heat to each other. Claim 1
The hot water supply device according to any one of claims 1 to 3. 5. The fluid heat transfer tube is configured to have a larger diameter than the hot water supply heat transfer tube, and circulates the fluid to be heated between the fluid heat exchanger and a heat consuming terminal. Fluid circulating means for circulating in the fluid circulating circuit including a bypass path for the fluid to be heated, which supplies the fluid to be heated in the outgoing path to the inflow path, is provided. 5. The system according to claim 4, wherein said fluid circulation means is operated.
A hot water supply device according to item 1. 6. The heat exchanger for hot water supply is provided with a heat transfer tube for hot water supply for flowing hot and cold water in the heat exchanger for hot water supply, and the heat exchanger for fluid is constituted by the heat exchanger for fluid. A heat transfer pipe for fluid that allows the fluid to be heated to flow therethrough, wherein the heat exchanger for hot water supply and the heat exchanger for fluid are configured so that a part of an outer peripheral portion of the heat transfer pipe for hot water supply and the fluid The hot water supply apparatus according to any one of claims 1 to 3, wherein a part of an outer peripheral portion of the heat transfer tube is brought into contact with the heat transfer tube so as to be integrally formed so as to conduct heat to each other. 7. A fluid including a bypass passage for a fluid to be heated, which circulates the fluid to be heated between the heat exchanger for fluid and a heat consuming terminal or supplies the fluid to be heated in the outlet to the inlet. 7. A fluid circulation means for circulating in a circulation circuit, wherein the control means is configured to operate the fluid circulation means during execution of the heat retention control processing.
A hot water supply device according to item 1. 8. A hot water supply temperature detecting means for detecting a temperature of hot water in the hot water supply heat exchanger, and a fluid temperature detecting means for detecting a temperature of a fluid to be heated in the fluid heat exchanger. The control means, during the heat retention control process, if any of the temperature detected by the hot water supply temperature detection means or the temperature detected by the fluid temperature detection means is equal to or higher than the set temperature for preventing boiling, the burner The hot water supply device according to any one of claims 1 to 7, wherein the hot water supply device is configured to stop combustion. 9. A hot water supply system comprising a bypass passage for supplying water supplied through the water supply passage to the hot water supply passage bypassing the hot water supply heat exchanger, wherein the hot water and the hot water heated by the hot water supply heat exchanger are provided. 9. The hot water supply system according to claim 1, wherein the hot water is supplied through the hot water supply path by mixing with water from a bypass path.
The hot water supply device according to the item. 10. The hot water supply apparatus according to claim 1, wherein the control unit is configured to determine that the heat retention start condition is satisfied when the freeze prevention start condition is satisfied. .