JPH1073263A - Operation control method of dual temperature type hot water circulating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the temperature rise of bathtub water and to prevent the decrease of low temperature load capacity when a bath heating device starts anti-freeze operation simultaneously when many low temperature loads are connected and the individual operation of low temperature heating is being run by opening a thermal valve of a bath heater circulating passage. SOLUTION: In a state that high temperature water is supplied to an inner circulating water passage 76 from a bypass pipe 100 and a bath heater circulating passage 98 by opening a thermal valve 99 of the bath heater circulating passage 98 when many low temperature loads 75 are connected, when an external temperature detecting sensor 68 detects anti-freezing temperature, a bath heating device 34 runs an anti-freezing operation for a predetermined time after stopping operation of a dual temperature type hot water circulating device 33 in the case of the individual operation of low temperature loads.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the operation of a two-temperature hot water circulation system. Specifically, the present invention provides:
An operation control method of a two-temperature hot water circulating device that can heat hot water in a bathtub by circulating high-temperature water in a bath heater and low-temperature water in a low-temperature load, and exchanging heat between hot water and hot water in the bathtub by the bath heater. About.

[0002]

2. Description of the Related Art FIG. 1 shows a configuration of a conventional two-temperature hot water circulation device having a bath heater for exchanging heat with a bath circulation circuit of a bath heating device. In the two-temperature system hot water circulation device 1, a high-temperature load 3, such as a hot air radiator or a bathroom ventilation dryer, and a heat exchanger 2 are connected by a high-temperature water circulation path 4 and a return hot water circulation path 5, The hot water circulation path 4 is provided with an on-off valve 6 for supplying high-temperature water, and the return hot water circulation path 5 is provided with a circulation pump 7. In the case of these high-temperature loads 3, high-temperature water of about 80 ° C. is usually required.

A low-temperature water circuit 9 is branched from a branch portion 8 provided in the return hot-water circuit 5 downstream of the circulation pump 7, and the low-temperature water circuit 9 is connected via an on-off valve 10 for supplying low-temperature water. And is connected to a low-temperature load 11 such as a soft floor heating panel and a radiator for warm air. The return hot water circulation path 12 for collecting the hot water that has passed through the low-temperature load 11 is connected to the return hot water circulation path 5 upstream of the circulation pump 7. Further, a bypass 13 is branched from the high-temperature water circulation path 4 upstream of the on-off valve 6 for supplying high-temperature water, and a pipe end of the bypass 13 is connected to the return hot-water circulation path 5 upstream of the circulation pump 7. The high temperature water heated by the heat exchanger 2 is directly connected to the branch portion 8. In the case of a low-temperature load 11, such as a soft floor heating panel that circulates warm water under the floor to warm the floor, or a micro-heat radiator that gently warms the room by flowing low-temperature hot water through the radiating fins installed in the room A high temperature is not required as the temperature of the hot water to be circulated, and a low temperature of about 60 ° C. is usually sufficient.

When supplying high-temperature water to the high-temperature load 3, the on-off valve 10 for supplying low-temperature water is closed and the on-off valve 6 for supplying high-temperature water is opened. When the circulation pump 7 is operated in this state, the high-temperature water heated and generated in the heat exchanger 2 is supplied to the high-temperature load 3 through the high-temperature water circulation path 4, and the high-temperature water circulates through the high-temperature load 3, so that the high-temperature heating is performed. And so on. Hot water that has passed the high-temperature load 3 returns to the heat exchanger 2 again through the return hot water circulation path 5. Near the exit of heat exchanger 2,
A first temperature sensor 14 for monitoring the temperature of the high-temperature water is provided.
The heat exchanger 2 is driven and controlled based on the temperature detection output of the above, and high-temperature water having a substantially constant temperature is circulated to the high-temperature load 3.

When supplying low-temperature water to the low-temperature load 11, the circulating pump 7 is operated with the on-off valve 6 for supplying high-temperature water closed and the on-off valve 10 for supplying low-temperature water opened. Circulate. Then, the high-temperature water heated and generated by the heat exchanger 2 passes through the bypass 13 and is branched at the branch portion 8, and a part of the high-temperature water returns to the heat exchanger 2, and the other part passes through the on-off valve 10 for supplying low-temperature water. Then, it flows toward the low-temperature load 11. in this case,
The heat exchanger 2 is driven and controlled based on the detection output of the second temperature sensor 15 provided at a position close to the on-off valve 10 for supplying the low-temperature water, that is, at the branch portion 8, so that the low-temperature load 11 Is supplied.

In the middle between the heat exchanger 2 and the on-off valve 6, a bus heater circulation path 17 for circulating the bus heater 16 from the high-temperature water circulation path 4 branches off.
Numeral 7 passes through the bath heater 16, returns to the pipe end, and is connected to the hot water circulation path 5. Reference numeral 18 denotes an on-off valve provided in the bus heater circulation path 17. On the other hand, the bath tub 19 has a bath heater 2
0 is provided, and both ends of a bath circulation circuit 22 are connected to a bus adapter 21 of a bathtub 19. The bath circulation circuit 22 circulates through the bath heater 16, and heat exchange can be performed between bath water flowing through the bath circulation circuit 22 and high-temperature water flowing through the bath heater circulation path 17. 23 is a bath circulation pump provided in the bath circulation circuit 22.

When the circulating pump 7 is operated with the on-off valve 10 for supplying low-temperature water closed and the on-off valve 18 of the bus heater circulation path 17 opened, the bus heater circulation path 17 is heated by the heat exchanger 2. High temperature water circulates. at the same time,
When the bath circulation pump 23 of the bath circulation circuit 22 is operated,
The bathtub water is forcibly circulated through the bath circulation circuit 22 and is heated by exchanging heat with high-temperature water by the bath heater 16, so that the hot water in the bathtub 19 is heated. Therefore, for example, it is possible to keep the temperature of the bathtub 19 so that the hot water does not cool down, or to reheat the water.

[0008]

In the two-temperature system hot water circulating apparatus 1 as described above, a plurality of low-temperature loads 11 are connected during low-temperature heating alone operation in which low-temperature water is circulated through the low-temperature load 11. Therefore, the heating capacity may be insufficient with only the high-temperature water passing through the bypass 13.

Therefore, when the heating capacity is insufficient only with the high-temperature water passing through the bypass passage 13 due to the large amount of the low-temperature load 11, the on-off valve 18 of the bus heater circulation passage 17 is opened, and the bypass passage 13 and the bus heater circulation passage 17 are opened. Through both, more hot water is supplied to the branch portion 8 and mixed with the heated return hot water flowing through the return hot water circulation path 5.

If a large-diameter bypass path 13 is used in advance to cope with a large low-temperature load 11,
Such problems can be avoided. However, if the diameter of the bypass passage 13 is too large, the heating capacity becomes excessive during low-temperature heating by the normal low-temperature load 11, and the start and stop of combustion of the burner for heating the heat exchanger 2 are frequently repeated and become unstable. Become. Therefore, it is inconvenient if the diameter of the bypass path 13 is too large. Therefore, usually, the bypass path 13 having an appropriate diameter for one standard low-temperature load 11 is designed.

On the other hand, the bath circulation circuit 22 has a large heat radiation,
Since the water in the bath circulation circuit 22 may freeze in winter, the bath heating device 20 performs the freeze prevention operation under certain conditions in winter. That is, the bath heating device 20
Detects the outside air temperature with the outside air temperature detection sensor 24. If the temperature detected by the outside air temperature detection sensor 24 becomes lower than the predetermined freezing prevention temperature, the bath circulation pump 23
Is operated for a certain period of time (time sufficient for the water in the bath circulating circuit 22 to replace the hot water in the bathtub 19), and the hot water in the bathtub 19 is circulated to the bath circulating circuit 22 to prevent the bath circulating circuit 22 from freezing. Are doing. Further, the temperature of the hot water in the bathtub 19 is detected by a bath thermistor (not shown), and after the elapse of an interval time corresponding to the hot water temperature, the bath circulation pump 23 is repeatedly operated for a predetermined time to prevent freezing. I have.

In the two-temperature type hot water circulating apparatus 1 having the above-described operation method, a plurality of low-temperature loads 11 are connected, and the on-off valve 18 of the bus heater circulation path 17 is opened to perform the low-temperature heating independent operation. In some cases, the bath heating device 20
When the antifreeze operation starts, the hot water in the bath unnecessarily rises because high-temperature water flows in the bath heater circulation path 17, and there is a problem that the bathing temperature becomes higher than the set bathing temperature and the bathing sensation deteriorates. .

At the same time, the high-temperature water flowing through the bath heater circulation path 17 exchanges heat with the hot water flowing through the bath circulation circuit 22 to lose heat, so that the temperature of the high-temperature water flowing through the bus heater circulation path 17 decreases. As a result, the low-temperature hot water circulates through the low-temperature load 11 and cannot supply sufficient heat.
However, there is a problem in that the performance of the heating device 1 is deteriorated, and the usability of the heating device as the low-temperature load 11 is deteriorated.

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and has as its object the purpose of opening the thermal valve of the bus heater circulation path and performing low-temperature heating alone operation. At the same time, even if the bath heating device starts the freezing prevention operation, it is to prevent the hot water temperature of the bath from rising and the capability of low-temperature load from decreasing.

[0015]

DISCLOSURE OF THE INVENTION The operation control method of the two-temperature type hot water circulating apparatus of the present invention is to heat and generate high-temperature water by a heat exchanger and to circulate the high-temperature water to the bath heater by opening a bath heater circulation path to heat the bathtub water. And circulating the low-temperature water to the low-temperature load in a two-temperature system hot water circulating apparatus that mixes the high-temperature water and return hot water supplied through the bypass path by opening the low-temperature water circulation path and circulates the low-temperature water to the low-temperature load. In the operation mode, when the heating capacity of the low-temperature water is insufficient, the flow rate of the high-temperature water supplied to the low-temperature water circulation path is increased by opening the bath heater circulation path,
In the operation mode in which the bath heater circulation path is opened and the low-temperature water is circulated to the low-temperature load, when the bath heating device connected to the bath heater starts the freeze prevention operation, the circulation of the high-temperature water to the bus heater is stopped. It is characterized by stopping.

In the two-temperature type hot water circulating apparatus, when low-temperature water is circulated to a low-temperature load, for example, to perform low-temperature heating, high-temperature water supplied through a bypass and return water are mixed to generate low-temperature water. The low-temperature water is circulated from the low-temperature water circuit to the low-temperature load.

In addition, when the heating capacity of the low-temperature load is insufficient, for example, when the number of low-temperature loads is large, in such a case, the high-temperature water is supplied from both the bus heater circulation path and the bypass path by opening the bus heater circulation path. Can be supplied, so that the heating capability of the low-temperature load can be increased.

In addition, when the bath heating device connected to the bath heater performs the freeze prevention operation, the circulation of the high-temperature water to the bath heater is stopped. Water can be prevented from flowing to the low-temperature load, and the use feeling of the soft floor heating panel, the low-temperature air radiator, and the like, which are the low-temperature load, can be prevented from being deteriorated. In addition, it is possible to prevent the bathtub water from being unnecessarily heated and the hot water temperature in the bathtub becoming too high, thereby deteriorating the bathing feeling.

Further, as described in claim 2, the combustion of the combustion device for heating the heat exchanger is stopped,
By stopping the operation of the circulation pump for circulating the high-temperature water and the low-temperature water to stop the circulation of the high-temperature water to the bus heater, the responsiveness is higher than that of opening and closing the thermal valve of the bus heater circulation path. It becomes better, and the circulation stop time of high-temperature water can be shortened.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

(Hot water heating / bath heating device) FIG.
It is a figure which shows the structure of the hot-water heating and bath heating apparatus 31 which consists of a temperature-type hot-water circulation apparatus 33 and a bath heating apparatus 34. The hot water supply device 32 is for supplying hot water to a toilet in a washroom or a kitchen, or for dropping hot water into a bathtub. The two-temperature type hot water circulation device 33 heats and generates high-temperature water by a heat exchanger, circulates the high-temperature water to a high-temperature load such as a hot-air radiator, a bathroom ventilation dryer, and performs high-temperature heating and returns hot water. Branch part, soft floor heating panel,
The heater is circulated to a low-temperature load such as a micro-hot air radiator to perform low-temperature heating, and further circulates high-temperature water to a bath heater to heat bathtub water. The bath heating device 34 circulates bath water through a bath heater to reheat the hot water in the bath tub, and to prevent the bath circulation circuit from freezing in winter. Hereinafter, the hot water / bath heater 31 will be described with reference to FIG.

(Hot water supply device) A heat exchanger 36 is provided in the upper part of the can 35 of the hot water supply device 32, and a gas burner 37 is provided immediately below the heat exchanger 36. Further, a blower fan 39 which is driven by a motor 38 and supplies combustion air to a gas burner 37 is provided therebelow, and an exhaust port 40 for discharging burned exhaust gas is opened on an upper surface of the can body 35. ing.

A water inlet pipe 41 is connected to the inflow side of the heat exchanger 36, and a hot water pipe 42 is connected to the outflow side of the heat exchanger 36. Further, the water inlet pipe 41 and the hot water pipe 42 are connected to the heat exchanger 3 by a bypass pipe 44 having a water flow control valve 43.
6 are bypassed. A flow sensor 45 and a water temperature sensor 4 are provided on the heat exchanger inflow side of the water inlet pipe 41.
A tapping temperature sensor 47 is provided on the outlet side of the heat exchanger of the tapping pipe 42, and a mixing point with the tapping flow control valve 48 is provided downstream of the junction of the tapping pipe 42 with the bypass pipe 44. A temperature sensor 49 is provided.

The heat exchanger 36 is heated by the combustion of the gas burner 37 and heats the water flowing through the heat exchanger 36.
Fuel gas is supplied to the gas burner 37 through a gas supply pipe 50, and the gas supply pipe 50 is provided with an electromagnetic on-off valve 51, a gas proportional valve 52, and a combustion capacity switching valve 53. The control unit (not shown) of the hot water supply device 32 includes an incoming flow rate Q1 detected by the flow rate sensor 45, a water temperature Tc detected by the water temperature sensor 46, a tapping temperature Th detected by the tapping temperature sensor 47, and mixing. Based on the hot and cold water mixing temperature Tm detected by the temperature sensor 49, the gas proportional valve 52 (or the combustion capacity switching valve 53) and the bypass pipe 44 are set so that hot water at the set temperature is discharged from the end of the tapping pipe 42. The water flow regulating valve 43 is controlled. At the end of the tapping pipe 42, a currant 54 or the like is provided to supply hot water to a washroom or a sink. The amount of hot water from hot water pipe 42 is controlled by hot water flow control valve 48.

(Bath Heating Device) In the bath heating device 34, both ends of a bath circulation circuit 57 are connected to a bus adapter 56 of a bathtub 55, and a bath heater 58 is provided in the bath circulation circuit 57. The bath circuit 57 has a water level sensor 5
9, a bath circulation pump 60, a bath water flow switch 61, and a bath water temperature sensor 62 are provided. A hot water supply pipe 63 branched from a pipe end portion of the hot water supply pipe 42 of the hot water supply device 32 is connected between the bath circulation pump 60 and the bath heater 58 of the bath circulation circuit 57. In this hot water supply pipe 63,
A vacuum breaker 64, an electromagnetic on-off valve 65, a flow sensor 66, and check valves 67, 67 are provided.

When the hot water is dropped into the bathtub 55, when the solenoid valve 65 is opened and the bath circulating pump 60 of the bath circulating circuit 57 is operated, the hot water of the hot water supply device 32 passes through the hot water supply pipe 63 from the bus adapter 56. The water is supplied into the bathtub 55, and hot water is applied to the bathtub 55. The dropping amount Q2 of hot water at this time is monitored by the flow rate sensor 66, and when the dropping amount Q2 reaches the set dropping amount, the electromagnetic on-off valve 65 is closed.

To reheat the hot water in the bathtub 55 that has already been set up, the bath circulation pump 60 is operated for a certain period of time to determine the circulation by the bath water flow switch 61, and the bathtub is detected by the water level detection sensor 59. After detecting the water level in the bath 55 and confirming that the hot water is filled above the position of the bath adapter 56, the bath circulation pump 60 is operated again to circulate the hot water in the bathtub 55 to the bath circulation circuit 57. Let
The bath water is heated by the bath heater 58 until the bath water temperature T3 detected by the bath water temperature sensor 62 reaches the set temperature.

Further, the bath heating device 34 performs a freezing prevention operation in winter. That is, the outside air temperature detection sensor 68 provided in the two-temperature system hot water circulation device 33
Accordingly, when it is detected that the outside air temperature _TF has become equal to or lower than the predetermined freezing prevention temperature, the bath circulation pump 60 is turned on for a certain period of time (when the water in the bath circulation circuit 57 is replaced with the hot water in the bathtub 55). The bath circulation circuit 5 is operated for a sufficient time and the hot water in the bathtub 55 is circulated through the bath circulation circuit 57.
7 to prevent the bath circulation circuit 57 from freezing. The bath temperature sensor 62 detects the temperature of the hot water in the bathtub 55, and after the elapse of the interval time corresponding to the hot water temperature, the bath circulation pump 60 is repeatedly operated for a predetermined time to prevent freezing.

(Two-Temperature Type Hot Water Circulating Device) The two-temperature type hot water circulating device 33 includes a hot water supply header 69, low temperature water supply headers 70a, 70b, 70c, and a hot water recovery header 71a common to high temperature water and low temperature water. 71b and 71c are provided. Adjustment of the circulating water passing through the low-temperature water supply headers 70a, 70b, 70c is performed by the heat operated valves 72a, 72b, 72c, and the driving of the heat operated valves 72a, 72b, 72c, etc. is controlled by a microcomputer including a microcomputer described later. It can be controlled by the device. The high-temperature water supply header 69 is connected to a high-temperature load 74 such as a bathroom ventilating / drying operation provided with an electromagnetic on-off valve 73, and the low-temperature water supply header 70a,
A low-temperature load 75 such as a soft floor heating panel or a slightly warm air radiator is provided in each of the thermal valves 72a, 72b, and 72c.
Connected via Each high temperature load 74 and low temperature load 75
From the hot water recovery headers 71a, 71b, 71
c to be collected.

The inside of the two-temperature type hot water circulation device 33 includes:
An internal circulation channel 76 for heating the hot water recovered from the hot water recovery headers 71a, 71b, 71c with the heat exchanger 79 is provided. The internal circulation channel 76 is expanded to absorb expansion and contraction of the circulating water. It is connected to a hot water supply header 69 via a tank 77, a circulation pump 78 and a heat exchanger 79. A heating water supply pipe 81 branched from the water inlet pipe 41 is guided to a drop 80 of the expansion tank 77.
By opening the on-off electromagnetic valve 82 of the heating water supply pipe 81,
Circulating water (city water) can be supplied from the water inlet pipe 41 to the two-temperature hot water circulation device 33 (expansion tank 77). 83 is an overflow pipe provided in the expansion tank 77.

Immediately downstream of the portion where the circulating pump 78 is located in the internal circulating water channel 76, a part of the circulating water is supplied to the low temperature water supply headers 70 a and 70 without passing through the heat exchanger 79.
b, 70c are provided with a branch portion 84 for directly supplying the circulating water to the branch water channel 85 separated from the branch portion 84.
Is supplied to the low-temperature water supply headers 70a, 70b, and 70c. Reference numeral 86 denotes a temperature sensor (referred to as a second temperature sensor) provided at the entrance of the branch portion 84. Between the hot water supply header 69 and the hot water recovery headers 71a, 71b, 71c, both headers 69; 71 are provided.
a, 71b, 71c bypass pipe 1 of predetermined inner diameter
00 is provided. The inner diameter of the bypass pipe 100 is 1
At the time of low-temperature heating by the low-temperature load 75 of the table, a predetermined amount of high-temperature water is bypassed so that low-temperature water supply headers 70a, 70b, 70
The thickness is set to a value that can sufficiently increase the temperature of the hot water supplied from c.

Accordingly, the high-temperature water supplied from the heat exchanger 79 is supplied directly to the high-temperature water supply header 69 from the internal circulation channel 76. In contrast, the low-temperature water supply header 70
A, 70b, and 70c are supplied with low-temperature water in which high-temperature water supplied through the bypass pipe 100 and circulating water supplied from the branch portion 84 are mixed.

On the other hand, even in the two-temperature hot water circulation device 33, a heat exchanger 79 is installed in the upper part of the can 87, and a gas burner 88 is installed below it. A gas branch pipe 89 branched from the gas supply pipe 50 of the hot water supply device 32 is connected to the gas burner 88, and an electromagnetic on-off valve 90, a gas proportional valve 91, and a combustion capacity switching valve 92 are provided in the gas branch pipe 89. It is interposed. A blower fan 94 driven by a motor 93 to supply combustion air to the gas burner 88 is provided below the gas burner 88, and an exhaust port 95 for discharging burned exhaust gas is provided on the upper surface of the can body 87. Is open.

The heat exchanger 79 in the internal circulation channel 76
Two temperature sensors 96,
97 are provided. One is an empty heating prevention temperature sensor 96, which operates at a high temperature of 100 ° C. or higher. For example, when the amount of circulating water is abnormally low and the temperature of the internal circulating water passage 76 rises abnormally, the temperature sensor 96 for preventing empty firing operates. The other is a temperature sensor (referred to as a first temperature sensor) 9 for detecting the temperature of the circulating water passing through the heat exchanger 79.
7 for use in temperature control.

On the outlet side of the heat exchanger 79,
A bus heater circulation path 98 branches from the internal circulation water path 76, and after circulating in the bus heater 58, the bus heater circulation path 98 is connected to the internal circulation water path 76 on the water inlet side of the expansion tank 77 through a thermal valve 99. ing. Thus, when high-temperature water is supplied from the heat exchanger 79 to the bath heater circulation path 98 and bathtub water is circulating in the bath circulation circuit 57, the high-temperature water and the bathtub water exchange heat to form bathtub water. Is heated. Reference numeral 68 denotes an outside air temperature detection sensor for detecting the outside air temperature.

(Control Method of Two-Temperature-Type Hot Water Circulation Apparatus) FIG. 3 is a block diagram showing an electric configuration of the control device 101 applied to the two-temperature-type hot water circulation apparatus 33. The control device 101 has a built-in microcomputer, and an input unit of the control device 101 includes a first temperature sensor 97, a second temperature sensor
A temperature sensor 86, an outside air temperature detection sensor 68, a temperature sensor 96 for preventing boil-off, a high-temperature controller 102 and a low-temperature controller 103 are connected, and a circulation pump 78, a thermal valve 99 of a bus heater circulation path 98, Electromagnetic on-off valve 73 for high temperature load 74, low temperature water supply head 70
a, 70b, 70c thermal valves 72a, 72b, 72c,
Solenoid on-off valve 90, gas proportional valve 91 and combustion capacity switching valve 9
2 are connected. The high-temperature controller 102 is for controlling the high-temperature load 74 such as a bathroom ventilation dryer and is arranged at any place in the building, and includes a heating switch for starting heating, a pilot lamp, and the like. The low-temperature controller 103 is for controlling a low-temperature load 75 such as a soft floor heating panel and a slightly warm air radiator, and is installed for each installation location of each low-temperature load 75. For example, if there are five rooms and floor heating is applied to each room, five low-temperature controllers 103 are provided for each room.

(During high-temperature load operation) The control device 101 detects an operation start signal from the high-temperature controller 102, an operation start signal from the low-temperature controller 103, or temperature detection from any of the temperature sensors 97, 86, 68, and 96. A predetermined determination is made based on the signal, a drive signal is sent to the circulation pump 78, and the gas proportional valve 9
The circulating water is controlled to a predetermined set temperature by sending a gas amount adjustment signal to the combustion performance switching valve 92 or a gas opening / closing signal to the electromagnetic opening / closing valve 90.

That is, the control device 101 receives the operation start signal from the high temperature controller 102, and the thermal valves 72a, 72 of the low temperature water supply headers 70a, 70b, 70c.
b and 72c are closed, the water is circulated by operating the circulation pump 78 in a state where the electromagnetic switching valve 73 of the high temperature load 74 is opened, and based on the detection output of the first temperature sensor 97,
The circulating water is heated on the basis of 80 ° C. by sending a gas amount adjustment signal to the gas proportional valve 91 or sending a signal to the electromagnetic switching valve 90 or the combustion capacity switching valve 92 as necessary. Can be controlled. In this way 2
The heating of the high temperature load 74 in the temperature type hot water circulation device 33 is performed by keeping the temperature of the hot water supplied to the high temperature water supply header 69 constant.

(During Operation of Bath Heating Apparatus) A case where the additional heating of hot water in the bathtub 55 by the bath heater 58 is performed alone will be described. When the reheating switch (not shown) is pressed to start the reheating operation, the bath heating device 34 causes the bath 55
After confirming that there is residual water equal to or higher than a predetermined water level, the bath circulation pump 60 is operated to circulate the hot water in the bathtub 55 to the bath circulation circuit 57. When receiving the signal for starting the additional heating operation from the bath heating device 34, the high temperature controller 102
Electromagnetic switching valve 73 for high temperature load 74 and header 7 for supplying low temperature water
0a, 70b, 70c thermal valve 72a, 72b, 72c
Is closed, and the thermal valve 99 of the bus heater circulation path 98 is opened. When the thermal valve 99 of the bath heater circulation path 98 is opened, the high-temperature water flowing out of the heat exchanger 79 flows through the bus heater circulation path 98, so that the high-temperature water of the bath heater circulation path 98 and the bathtub water of the bath circulation circuit 57 are separated. By exchanging heat, the bathtub 55
The hot water inside is heated.

(During Low-Temperature Load Operation) Next, a case will be described in which low-temperature water is supplied only to the low-temperature load 75 such as a soft floor heating panel or a slightly warm air radiator. Low temperature controller 103
Is operated, a low-temperature operation start signal from the low-temperature controller 103 is input to the control device 101. Then, the control device 101 closes the electromagnetic on-off valve 73 of the high-temperature load 74, and the thermal valve 72 of the low-temperature water supply headers 70a, 70b, 70c.
The high-temperature water is circulated by operating the circulating pump 78 with the a, 72b, and 72c open. A part of the circulating water discharged from the circulating pump 78 passes through the low temperature water supply headers 70a, 70b, 70c directly from the branch portion 84, and the low temperature load 7
It flows toward 5. The remainder of the circulating water discharged from the circulation pump 78 enters the heat exchanger 79, where it is heated and returned to the circulation pump 78 again through the bypass pipe 100. Therefore, the low-temperature load 75 has the bypass pipe 1
The low-temperature water in which the high-temperature water supplied through 00 and the circulating water supplied from the branch portion 84 are mixed is supplied from the low-temperature water supply headers 70a, 70b, 70c.

However, the diameter of the bypass pipe 100 is designed on the assumption that one low-temperature load 75 is connected to the low-temperature water supply headers 70a, 70b, 70c, for example. When the number of low-temperature loads 75 (for example, two or more) is larger than the assumed number of the low-temperature loads 75a, 70b, and 70c, the temperature of the low-temperature water decreases and the heating capacity becomes insufficient, and the low-temperature load 75 decreases. The heating capacity of 75 will be reduced. For this reason, the low-temperature controller 10
Numeral 3 monitors the number of low-temperature loads 75 connected to the low-temperature water supply headers 70a, 70b, 70c, and if the number of low-temperature loads 75 exceeds the assumed number, the low-temperature water supply headers 70a, 70b, 70c. If you are connected to
The thermal valve 99 of the bus heater circulation path 98 is opened to supply the high-temperature water to the circulation pump 78 from both the bus heater circulation path 98 and the bypass pipe 100 at the same time, and to prevent the temperature of the low-temperature water supplied to the low-temperature load 75 from becoming too low. To prevent.

Further, when the low-temperature load 75 is operated,
The number of connected low-temperature loads 75 is large and the bus heater circulation path 98
When the outside air temperature detection sensor 68 detects a predetermined freezing prevention temperature when the thermal valve 99 is opened, a signal is output from the low-temperature controller 103 to the control device 101, and the control device 101 The operation of the hot water circulation device 33 is stopped. That is, the control device 101 closes the electromagnetic on-off valve 90 to stop the combustion of the gas burner 88, and also stops the circulation pump 78 to stop the circulation of the high-temperature water. In a state where the operation of the two-temperature hot water circulation device 33 is stopped in this way, the bath heating device 34 operates the bath circulation pump 78 to perform the freeze prevention operation.

At this time, since high-temperature water is not circulating in the bath heater 58, it is possible to prevent the temperature of the hot water in the bathtub 55 from becoming too high and the bathing sensation being deteriorated even when the bath heating device 34 performs the freeze prevention operation. it can. In addition, the bath heater 5
The hot water whose temperature has been lowered by the heat exchange in step 8 can be prevented from being supplied to the low-temperature load 75 from the low-temperature water supply heads 70a, 70b, 70c. Since the low-temperature load 75 generally has a small amount of heat radiation, such as hot water floor heating, the low-temperature load 75 is maintained for a certain period of time (for example, 50 seconds) during which the bath circulation pump 78 is operated, even if the hot water is stopped. The feeling of use does not get so bad. On the contrary, the feeling of use is much better than when low-temperature hot water circulates through the low-temperature load 75.

(Control Method for Preventing Freezing Operation) FIG. 4 shows that the number of connected low-temperature loads 75 is large, and the two-temperature type hot water circulation device 33 opens the heat valve 99 of the bus heater circulation path 98 to heat by the low-temperature load 75. It is a flowchart which shows the operation | movement procedure of the freezing prevention operation | movement of the bath heating apparatus 34 when performing. Hereinafter, description will be made with reference to FIG.

First, the bath heating device 34 and the two-temperature hot water circulation device 33 monitor whether or not the detected temperature _TF of the outside air temperature detecting sensor 68 has dropped to the freezing prevention temperature (S111). When the temperature is lowered, the bath temperature of the bath temperature sensor 62 is checked (S112). If the temperature is equal to or higher than a predetermined temperature Ts (for example, 18 ° C.), it is checked whether the low-temperature load 75 is operated alone (S113). In the case of operation, the two-temperature type hot water circulation device 33 is stopped by stopping the combustion of the gas burner 88 and the operation of the circulation pump 78 (S114), and then the bath circulation pump 60 is started (S115). The freezing of the circulation circuit 57 is prevented.

Therefore, the heat exchange between the bath water flowing through the bath circulation circuit 57 and the high-temperature water flowing through the bath heater circulation path 98 can be avoided by the freezing prevention operation, so that the temperature of the bath water can be prevented from becoming too high. In addition, low-temperature load 7
It is also possible to prevent the circulating water having a low temperature from flowing to 5 and lowering the heating capacity of the low-temperature load 75. During this time, the low temperature load 75
Is not supplied with the low-temperature water, and the heating by the low-temperature load 75 is not performed. However, since the low-temperature load 75 has a small amount of heat radiation, the bath circulation pump 60 is operated for a short time (for example, about Even if the low-temperature water does not circulate to the low-temperature load 75 for 50 seconds), the usability does not deteriorate so much. On the contrary, the feeling of use becomes better than the flow of the low-temperature hot water through the low-temperature load 75.

On the other hand, the two-temperature type hot water circulation device 33
Is not the single operation of the low-temperature load 75, but is, for example, the operation of the high-temperature load or the parallel operation of the low-temperature load 75 and the high-temperature load (NO in step S113). The operation of the bath circulation pump 60 is started without stopping the circulation device 33 (S1).
15) Prevent the bath circulation circuit 57 from freezing. Since the high-temperature load has a large heat radiation amount, when high-temperature water is flowing through the high-temperature load, the circulation of the high-temperature water is not stopped unlike the low-temperature load 75.

When the operation of the bath circulation pump 60 is started to prevent freezing, the bath heating device 34 monitors whether or not the bath water flow switch 61 has been continuously turned on for a predetermined time (for example, 50 seconds). (S116). If the bath water flow switch 61 has not been turned on for a certain period of time (for example, one minute) (S122), it is determined that there is no remaining hot water above the bath adapter level in the bathtub 55, and the bath circulation pump 60 is stopped ( S123), the freezing prevention is performed by heating the bath circulation circuit 57 with another processing means, for example, an electric heater (not shown) installed near the bath circulation circuit 57 (S124).

When the bath water flow switch 61 is continuously turned on for a certain period of time, it is determined that bath tub water in the bath tub 55 has circulated through the bath circulation circuit 57 and the bath circulation circuit 57 has been sufficiently heated. Stop the circulation pump 60 (S11)
7). At the same time, if the two-temperature hot water circulation device 33 has been stopped in step 114, the gas burner 88 is burned and the circulation pump 78 is started to put the two-temperature hot water circulation device 33 into the operating state ( S1
18).

Next, the bath temperature is detected by the bath temperature sensor 62, and an interval time for performing the anti-freezing operation again is determined by the bath temperature T detected by the bath temperature sensor 62.
3 is set (S119). Then, when the interval time has elapsed (S120), the freezing prevention operation is executed again (S111 to S111).

Here, the bath heating device 34 compares the detection temperature _TF of the outside air temperature detection sensor 68 with the detection temperature T3 of the bath hot water temperature sensor 62 until the interval time of step 12 elapses. The interval time is corrected according to the detected temperatures _TF and T3 (S121).

The correction of the interval time may be performed at any time when the detected temperature _TF of the outside air temperature detecting sensor 68 and the detected temperature T3 of the bath water temperature sensor 62 are constantly monitored and the change becomes large. Often, a certain number of times (for example,
It may be limited to only once. Step S120
Until the interval time elapses, the low-temperature load 7
5 (ie, because the gas burner 88 is burning, the ambient temperature in the two-temperature hot water circulation device 33 becomes higher than the outside air temperature and the bus heater 58
The high-temperature water circulates inside the bath, so that a little heat is also transmitted to the bath water temperature sensor 62), so that the correction tends to increase the interval time. There is a risk of passing. Therefore,
The correction of the interval time is preferably limited to a certain number of times, particularly only once, as in the latter case.

In step 112, when the detected temperature T3 of the bath water temperature sensor 62 is lower than a predetermined temperature Ts (this temperature is preferably set to a slightly higher value, for example, it can be set to 18 ° C.). Even in the case of the single operation of the low-temperature load 75, the antifreeze operation is performed without stopping the operation of the two-temperature hot water circulation device 33 and stopping the low-temperature heating by the low-temperature load 75. This is because when the temperature of the bathtub water is low, the bath heating device 34 frequently performs the antifreezing operation (that is, the interval time becomes very short), and the heating by the low-temperature load 75 is stopped many times. To get rid of it.

That is, if the detected temperature T3 of the bath temperature sensor 62 is lower than the fixed temperature Ts, the operation of the two-temperature type hot water circulation device 33 is not stopped, so that the bath heating device 34
Performs freezing prevention operation, and when low-temperature bath water flows through the bath circulation circuit, the bath water is heated by the bath heater 58, so that the temperature of the bath water gradually increases. Therefore, while the temperature of the bathtub water is low, the low-temperature heating by the low-temperature load 75 is not stopped, and when the bathtub water is heated to a temperature equal to or higher than the predetermined temperature Ts, the two-temperature hot water circulation device 33 operates at a predetermined interval time. Stopped. At this time, since the interval time of the freeze prevention operation is long, the low-temperature load 7
There is no inconvenience that the low-temperature heating by 5 is frequently stopped.

In the above-described embodiment, when the low-temperature water supply capacity is insufficient and the low-temperature water is supplied to the low-temperature load 75 by opening the thermal valve 99 of the bus heater circulation path 98, the bath heating device 34 operates to prevent freezing. Is started, the combustion of the gas burner 88 is stopped and the circulating pump 78 is stopped.
You can just close the. However, until the thermal valve 99 of the bus heater circulation path 98 is closed,
Since it takes about 50 minutes to stop the two-temperature hot water circulating device 33 in about 50 seconds, the method of stopping the two-temperature hot water circulating device 33 has better responsiveness and lower load of the low-temperature load 75 as described above. Since the operation stop time is shortened, the usability is excellent.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a conventional two-temperature hot water circulation device.

FIG. 2 is a diagram showing a configuration of a hot water supply / bath heating device including a two-temperature hot water circulation device according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a control unit of the two-temperature system hot water circulation device according to the first embodiment;

FIG. 4 is a flowchart illustrating a control method during low-temperature load operation of the above-described two-temperature hot water circulation device.

[Explanation of symbols]

 32 hot water supply device 33 two-temperature hot water circulation device 34 bath heating device 57 bath circulation circuit 58 bath heater 60 bath circulation pump 62 bath hot water sensor 68 outside air temperature detection sensor 69 header for supplying high-temperature water 70a, 70b, 70c header for supplying low-temperature water 71a, 71b, 71c Hot water recovery header 73 Solenoid on-off valve 74 High temperature load 75 Low temperature load 76 Internal circulation channel 78 Circulation pump 79 Heat exchanger 84 Branch section 85 Branch water channel 86 Second temperature sensor 88 Gas burner 90 Electromagnetic switching valve 91 Gas proportional Valve 97 First temperature sensor 98 Bus heater circulation path 99 Thermal valve 100 Bypass pipe 101 Control device

Claims (2)

[Claims] 1. A high-temperature water is heated and generated by a heat exchanger, a high-temperature water is circulated to a bath heater by opening a bath heater circulation path to heat bathtub water, and supplied through a bypass path by opening a low-temperature water circulation path. If the heating capacity of the low-temperature water is insufficient in the operation mode in which the low-temperature water is circulated to the low-temperature load in the two-temperature system hot water circulator that circulates the low-temperature water to the low-temperature load by mixing the collected high-temperature water and return hot water In the operation mode in which the flow rate of high-temperature water supplied to the low-temperature water circulation path is increased by opening the bath heater circulation path and the low-temperature water is circulated to the low-temperature load by opening the bus heater circulation path, When the bath heater that starts is to start the freezing prevention operation, the circulation of the high-temperature water to the bath heater is stopped. Operation control method in degrees type hot water circulation system. 2. A method of stopping circulation of high-temperature water to a bus heater by stopping combustion of a combustion device for heating a heat exchanger and stopping operation of a circulation pump for circulating high-temperature water and low-temperature water. The operation control method for a two-temperature system hot water circulation device according to claim 1, wherein: