JP3266510B2 - Antifreezing method and antifreezing device for gas hot water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for preventing freezing in a gas water heater. Specifically, while preventing the freezing of the terminal heater by intermittently operating the heating hot water generation means, in this antifreeze operation mode, during the intermittent pause of the heating hot water generation means,
The present invention relates to a freezing prevention method and a freezing prevention device for a gas hot water supply / room heater that can solve the inconvenience when the hot water supply / hot water generation means is operated.

[0002]

2. Description of the Related Art A gas hot water supply / room heater is provided with a hot water supply / hot water generator for supplying hot water to a faucet or a bath, and a heating / hot water generator for circulating hot water to a terminal heater.
The hot water generated by the heating hot water generating means is circulated and supplied to the terminal heater by a circulation pump.

[0003] Each of the above hot water generating means is provided with an intake fan for taking in outside air.
In conjunction with the operation of each hot water generating means, these intake fans are also operated, and air required for gas combustion is introduced into the combustion device of each hot water generating means. The heating circuit reaching the terminal heater is often exposed to outside air, and it is necessary to prevent freezing in winter. For this reason, it is detected that the temperature has fallen below the predetermined freezing dangerous temperature, the antifreezing operation mode is entered, and the above-mentioned heating hot water generating means is operated to perform the antifreezing operation.

[0004] The anti-freezing operation is performed by intermittently circulating hot water required for anti-freezing to each terminal heater by operating the heating hot water generating means intermittently and at a low temperature.

[0005]

The hot water supply side intake fan attached to the hot water supply hot water generation means and the heating side intake fan attached to the heating hot water generation means are controlled to operate in conjunction with each hot water generation means. At the same time, when one of the hot water generating means operates, the other intake fan is controlled to operate.

[0006] When only the intake fan attached to one of the hot water generating means is operated in conjunction with one of the hot water generating means, the exhaust gas generated by the operation of the hot water generating means is discharged through the other exhaust port into the operating combustion device. This is because the gas may be inhaled and may be incompletely burned. On the other hand, in the conventional gas water heater / heater, the circulation pump is controlled to operate in conjunction with the heating / hot water generating means. Therefore, when the heating / hot water generating means is at rest, the circulation pump is stopped at the same time.

However, after entering the anti-freezing operation mode,
When operating the hot water supply hot water generating means during the intermittent pause of the heating hot water generating means, the intake fans attached to both the hot water generating means operate together to cause a problem. That is,
When the heating-side intake fan is operated by the operation of the hot water supply hot water generating means, low-temperature outside air is introduced into the combustion device of the heating hot water generation means even though the heating hot water generating means is not operating.

In addition, since the anti-freezing operation is controlled so as to operate at a low temperature while suppressing the output of the heating hot water generating means, the temperature of the water generated during the anti-freezing operation and staying in the pipe near the hot water generating means is controlled. Is also lower than in normal operation.
For this reason, the operation of the heating-side intake fan significantly lowers the temperature of the heat-absorbing pipe in the heating-hot-water generating means, increasing the risk of freezing. Furthermore, if a normal heating operation is performed in a state where the heat absorbing pipe is frozen, a situation in which the heating hot water generating means is damaged due to a rapid temperature change may be considered.

The present invention solves the above-mentioned conventional problem. In the antifreezing operation mode of the heating circuit, even when the hot water supply hot water generating means is operated while the heating hot water generation means is intermittently stopped, the heating can be performed. An object of the present invention is to prevent a heat absorbing pipe section in a hot water generating means from freezing.

[0010]

Means for Solving the Problems To solve the above problems, the present invention takes the following technical means. The invention described in claim 1 of the present application is a hot water supply hot water generating means and a heating hot water generating means for generating hot water using a gas burner,
A hot-water supply-side intake fan and a heating-side intake fan that are respectively attached to each of the hot water generating means and introduce combustion air to these hot water generating means, and a circulation for circulating hot water generated by the heating hot water generating means to a terminal heater. A method for preventing freezing in a gas water heater / heater including a pump, wherein the method detects a temperature below the freezing dangerous temperature and enters an antifreezing operation mode, in which the heating hot water generating means, the heating side intake fan and the circulation pump are intermittently operated. In the anti-freezing operation mode, the hot water supply hot water generation means and the hot water supply side intake fan are operated during the intermittent pause of the heating hot water generation means by operating the heating circuit including the terminal heater. When the heating circuit is operated, the heating side intake fan is operated and the circulating pump is operated so that the heating circuit inside the gas water heater is operated. By circulating the water, characterized in that to prevent freezing of the heating circuit in the interior gas water heater.

The dangerous freezing temperature refers to the temperature at which the water in the circulation circuit starts to freeze, and can be based on atmospheric temperature, water temperature, or the like. The actual freezing temperature varies depending on the location of the hot water heater / heater, the location of each circuit, the water quality, etc. Generally, water freezes below 0 degrees Celsius. It is desirable to control by setting. Further, the place where the dangerous freezing temperature is detected is not particularly limited, and it can be detected in the gas water heater / heater main body, the terminal heater, or the like.

[0012] In the anti-freezing operation, the interval at which the heating hot water generating means and the circulation pump are intermittently operated, that is, the operation time and the downtime are determined by the length of the piping circuit for preventing freezing,
It is determined by the temperature gradient of the water in the pipe. In the anti-freezing operation, the anti-freezing operation can be performed by generating and circulating hot water lower in temperature than the hot water generated during the normal heating operation.

[0013] The invention described in claim 2 of the present application is a hot water supply hot water generating means and a heating hot water generating means for generating hot water using a gas burner, and combustion air is attached to each of the hot water generating means. A hot water supply-side intake fan and a heating-side intake fan, a circulation pump that circulates hot water generated by the heating hot water generation means to a terminal heater through a heating circuit, and an upstream of the terminal heater in the heating circuit. An antifreezing device for a gas water heater and a hot water supply device, comprising: a bypass circuit connecting the side and the downstream side in the main body in communication with each other; The temperature detecting means detects that the temperature is below the freezing dangerous temperature and enters an antifreezing operation mode, in which the heating hot water generating means, the heating side intake fan and the circulation pump are provided. By performing the intermittent operation, the anti-freezing operation of the heating circuit including the terminal heater is performed, and in the anti-freezing operation mode, the hot water supply hot water generation means and the hot water supply side intake fan during the intermittent suspension of the heating hot water generation means. When the air heater is operated, the heating side intake fan is operated and the circulation pump is operated to circulate the water in the heating circuit inside the gas hot water heater through the bypass circuit, thereby heating the inside of the gas hot water heater. Control means for preventing freezing of the circuit is provided.

The bypass circuit only needs to be able to circulate water inside the gas water heater / heater body, and a bypass circuit provided to prevent boiling when the heating hot water generating means is started can also be used. In addition, a bypass circuit dedicated to antifreeze operation may be separately provided. Furthermore, in a hot water supply / heater provided with a circuit for reheating a bath,
Water can be circulated inside the gas water heater using the bypass circuit for additional heating of the bath.

[0015] The invention described in claim 3 of the present application is configured such that the gas water heater / heater exchanges information with the terminal heater to control the opening / closing of the thermal valve of the terminal heater. A gas hot water heater, characterized in that when performing an antifreeze operation inside the gas hot water heater, opening / closing of a thermal valve or the like is controlled so as not to circulate hot water through the terminal heater. Conventionally, the terminal heating device is configured to operate independently of the hot water supply / heating device main body, and the freezing prevention operation of the heating circuit is performed unless both the hot water supply / heating device main body and the terminal heating device enter the anti-freezing mode. I didn't. For this reason,
If the conditions are different between the hot water supply / heating unit and the terminal heating unit, the antifreezing operation is not performed despite the need to prevent freezing, and the heating circuit may be frozen. In order to solve this problem, it is configured such that information can be exchanged between the hot water supply / heating unit and the terminal heating unit, and when one of the units needs to be prevented from freezing, the system is controlled to perform the freezing prevention operation. The invention of the present application is applied to the hot water supply / room heater provided.

In the present invention, it is only necessary to prevent freezing in the heating hot water generating means, and it is sufficient that water circulates inside the hot water supply / heating unit main body. Therefore, the invention described in the present invention controls the opening and closing of the thermal valve so that water does not circulate in the heating circuit up to the terminal heater.

[0017]

According to the present invention, when the hot-water supply / hot-water generator is operated during the intermittent stop of the heating / hot-water generator in the antifreeze operation mode, the intake fan attached to both the hot-water generators. Is activated, and the circulation pump is activated to circulate water in the heating circuit inside the gas water heater.

By circulating water inside the hot water supply / heating unit body, even if cold air is sucked into the heating / hot water generating means by the heating-side intake fan, it is possible to prevent the temperature of the heat-absorbing portion from being locally reduced, and Can be effectively prevented from freezing. Further, inside the gas hot water heater, there are heat sources such as hot water hot water generating means and a bath heater. Therefore, if the heating side intake fan is stopped, there is no possibility that the circuit will freeze after the circulation pump is stopped. Therefore, freezing can be effectively prevented by circulating water only when the heating-side intake fan is operating in a state where the heating hot water generating means is not operating.

Further, since only the water in the circuit inside the gas hot water heater is circulated, the temperature gradient of the heating circuit up to the terminal heater is not affected. Therefore, freezing inside the gas hot water heater can be effectively prevented without complicating the control. Furthermore, as in the invention described in claim 3, in a gas water heater that can exchange information between the hot water heater / main unit and the terminal heater, the circulation of water to the terminal heater is positively prevented. This does not affect the water temperature in the heating circuit that reaches the terminal heater. For this reason, there is no fear that the temperature of the water in the pipe changes and the effect of the normal anti-freezing operation is reduced.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 shows a schematic configuration of a gas water heater / heater to which the present invention is applied. The gas hot water supply / room heater 1 shown in FIG. 1 includes a hot water supply hot water generation unit 2 and a heating hot water generation unit 3. The hot water supply hot water generation means 2 and the heating hot water generation means 3 are connected to a hot water supply heating circuit 5 disposed in the hot water generation means 2 and 3 by a burner 2a, 3a which is supplied with gas from a gas supply pipe 4 and burns. The water flowing through the water heating circuit 6 is configured to be heated. Each of the hot water generating means 2 and 3 has an intake fan 2b,
3b is connected, and the air required for combustion of the burners 2a, 3a is introduced, and the combustion gas is discharged from the exhaust ports 2c, 3c, whose both openings are arranged in parallel on the front surface of the main unit of the gas water heater 1 for example. It is configured to forcibly discharge to the outside.

In the present embodiment, the bath water is reheated by the hot water generated by the heating hot water generating means 3, and the reheating heat exchanger 7 for performing liquid-liquid heat exchange is provided. , Is provided in the bath reheating circuit 8. A hot water supply circuit 9 for branching from the hot water supply heating circuit 5 of the hot water supply hot water generating means 2 and supplying hot water to the bathtub B through the bath additional heating circuit 8 is provided.
A hot water supply solenoid valve 10 is provided in the middle of the hot water filling circuit 9. The bath reheating circuit 8 is provided with a bath pump 11 for circulating hot water in the bathtub B.

A high-temperature terminal heater 13a such as a hot air heater or the like,
A high-temperature terminal heating circuit 14 provided with 13b and 13c, a low-temperature terminal heating circuit 16 provided with a low-temperature terminal heater 15a, 15b, 15c such as a floor heating device, and an upstream and a downstream of the high-temperature terminal heater. And a bath bypass circuit 12 that circulates and supplies hot water to the bath additional heating heat exchanger 7 to perform liquid-liquid heat exchange, and that is branched from the heating water heating circuit 6. ing. In the embodiment shown in FIG. 1, the heating water heating circuit 6, the high temperature side terminal heating circuit 14, and the low temperature side terminal heating circuit 16 constitute a heating circuit.

As shown in FIG. 2, each of the terminal heaters 13
a, 13b, 13c, 15a, 15b, and 15c have respective circulation system circuits 14a, 14b, 14c, 16a, and 16a.
b, a thermal valve 27 for controlling the circulation of water to 16c
a, 27b, 27c, 27d, 27e, 27f and a room temperature sensor 2 for detecting the room temperature at which each terminal heater is installed
8a, 28b, 28c, 28d, 28e, 28f and terminal-side control devices 29a, 29b, 29c, 29d, 29
e, 29f and operation units 30a, 30b, 30c, 30
d, 30e and 30f are provided respectively. Then, when circulating hot water to each terminal heater, each of the heat operated valves 27a to 27f is opened, while when not circulating hot water, the valves are closed.

The hot water flowing through each of the above circuits is cistern 17
And is circulated and supplied to each circuit by the circulation pump 18. In the heating water heating circuit 6, a high temperature water temperature detecting means 19 is provided on the tapping side of the heating hot water generating means 3, and a low temperature water temperature detecting means 20 is provided on the upstream side of the low temperature terminal heating circuit 16. In the embodiment, a thermistor is used as the water temperature detecting means.

Although detailed description is omitted, a predetermined portion of each circuit of the hot water supply / room heater 1 is provided with the temperature detecting means 1
A temperature sensor 21, a water amount sensor 22 and the like are provided in addition to the components 9 and 20, and a control device described later adjusts a water amount, a heating amount, and the like so that a desired amount of hot water can be supplied at a desired temperature. . In the present embodiment, a low-temperature sensing thermistor 23 is employed as the freezing dangerous temperature detecting means. The low-temperature sensing thermistor 23 is provided in the vicinity of the combustion air intake port of the hot water supply / room heater 1 so as to detect the temperature of the outside air flowing into the intake port to detect whether the temperature has fallen below the freezing dangerous temperature. It is configured.

The heating circuit in the main unit of the gas water heater is provided with a bypass circuit 26 connecting the upstream side and the downstream side of the heating circuit 14 reaching the high-temperature terminal heater. The bypass circuit 26 is provided for the purpose of preventing water in the circuit from boiling when the heating hot water generating means is started. Since high-temperature hot water flows through the bypass circuit 26 during the heating operation, the pipeline is set narrow to prevent energy loss.

On the other hand, in the bath bypass circuit 12,
On the upstream side of the bath additional heating heat exchanger 7, a thermal valve 24 is provided as a circuit opening / closing means. As shown in FIG. 2, control of the hot water supply / room heater 1 according to the present embodiment is performed by a central controller 25 incorporating a microcomputer. Further, the central control device 25 is connected to the hot water supply hot water generation means 2, the heating hot water generation means 3, the water temperature detection means 19, 20 and the like in the main body of the gas hot water supply / room heater 1, and controls the hot water supply temperature and the hot water supply amount. In addition, each terminal heater 13a,
13b, 13c, 15a, 15b, and 15c are connected to the respective terminal-side control devices 29a to 29f. The terminal control devices 29a to 29f and the central control device 25 exchange information with each other to control the opening and closing of the thermal valves of the terminal heaters. .

For example, the operating device 30 of the terminal heater 13a
When a heating start is instructed by a, the terminal-side control device 29a
, The thermal valve 27a of the terminal heater is opened and the heating start information is input to the central controller 25. Then, based on the information from the terminal heater 13a, the heating hot water generating means and the like are operated. In addition, when a freeze prevention operation mode described below is entered, the thermal valve 27a is opened from the central control device 25 via the terminal-side control device 29a.

Further, the room temperature information obtained by the room temperature sensor 28a is sent to the central control unit 25 via the terminal side control unit 29a, and the thermal valve 27a is controlled. It is configured to instruct the central controller 25. FIG. 3 shows a flowchart of the anti-freezing operation performed by the control device according to the present embodiment.

As shown in FIG. 3, when the heating operation is stopped (S
100), when the air temperature in the gas water heater / heater detected by the low temperature sensing thermistor 23 becomes 3 ° C. or less (S10).
1) Enter the antifreeze operation mode. When the freeze prevention operation mode is entered, the circulation pump 18 is turned on and the thermal valves of all terminal heaters are opened (S102). By operating the circulation pump for 3 minutes, the heating water in the heating circuit is mixed to make the temperature uniform (S103). If the water temperature detected by the high-temperature-side water temperature detecting means 19 does not rise above 20 ° C. (S104) ), It is determined that the anti-freezing operation is necessary, and the heating side intake fan 3b is operated, and at the same time, the burner 3a is burned to operate the heating hot water generating means 3 (S105).

After the heating hot water generating means 3 is operated, if the temperature of the heating water becomes 60 ° C. or higher, or after three minutes have elapsed (S106), the combustion of the burner 3a is stopped to release the heating hot water generating means. 3 and the heating-side intake fan 3b is stopped (S107). Thereafter, the circulation pump 18 is turned off, and all the terminal thermal valves 27a to 27f are turned off.
Is closed (S108).

Then, the interval timer provided in the central control unit is started, and the heating / hot water generating means 3 and the circulation pump 18 enter an intermittent rest time set in advance (S109). The intermittent pause time is set in advance based on the temperature change in the heating pipe, the length of the heating pipe, the number of terminal heaters, and the like. An object of the present invention is to eliminate the inconvenience that occurs when the hot-water / hot-water generating means 2 is operated during the intermittent pause of the heating / hot-water generating means 3 in the antifreezing operation mode. In the present embodiment, the following control is performed. It is configured to perform.

Normally, when the hot water supply hot water generating means 2 and the hot water supply side intake fan 2b operate for hot water supply (S110), the pump 18 and the heating side intake fan 3b attached to the heating hot water generation means 3 are controlled to operate. You. (S11
2). The heating side intake fan 3b is operated by the operation of the hot water supply hot water generating means 2 because the exhaust gas discharged from the exhaust port 2c of the combustion device of the hot water supply hot water generation means 2 is re-inhaled from the exhaust port 3c of the heating hot water generation apparatus 3. This is because the burner of the hot water supply / hot water generation means 2 may cause incomplete combustion.

When the heating side intake fan 3b is operated by using the hot water supply / hot water generation means 2, the heating hot water generation means 3
The outside air is introduced into the combustion chamber of the heating / hot water generating means 3 even though the burner 3a does not operate. by this,
The heat absorbing portion of the heating circuit 6 on the heating hot water generating means side is locally cooled, and the danger of freezing increases. In the present embodiment, the heating-side intake fan 3b and the circulation pump 18 are operated in conjunction with the operations of the hot-water / hot-water generating means 2 and the hot-water supply-side intake fan 2b (S112). When the circulation pump 18 is operated, the bypass circuit 2 provided between the outlet side and the return side to the terminal heater in the gas hot water heater main body.
Water circulates through 6. In the present embodiment, the circulation pump 18 is operated, and the thermal valve 24 is opened to circulate water through the bath bypass circuit 12.

In the present invention, freezing is prevented only by the heating circuit 6 which is affected by the outside air taken in by the heating-side intake fan 3b. Freezing can be effectively prevented. At this time, each terminal heater 13a, 13
The thermal valves b, 13c, 15a, 15b, and 15c are controlled via the central control device 25 and the terminal-side control device 29 so as to be kept closed. When water is circulated through the entire heating circuit to the terminal heater, the hot water in the external piping generated and supplied by the anti-freezing operation of the heating hot water generating means 3 circulates, and its temperature decreases. This is because the effect is reduced.

If the intermittent stoppage time ends during the operation of the hot water supply / hot water generation means 2 (S113), the thermal valves of all terminals are opened again to circulate the heating water (S10).
2) If necessary, the heating / hot water generating means 3 is operated to perform low-temperature combustion (S105), and the anti-freezing operation of the terminal heater is started again. On the other hand, if the hot water supply / hot water generation means 2 and the hot water supply side intake fan 2b stop before the intermittent pause time ends (S114), the heating side intake fan 3b is stopped and the circulation pump is stopped (S115). Wait for the end of time.

In the present embodiment, after the circulation pump 18 is stopped, the temperature inside the gas water heater is measured by the low temperature sensing thermistor 23, and when the temperature is 7 ° C. or more (S116), the freezing is performed. When it is determined that the preventive operation is not necessary, the antifreeze operation mode is released. Then, the temperature is detected again by the low-temperature sensing thermistor 23 to determine whether or not to enter the antifreeze operation mode.

Further, even when the hot water supply / hot water generating means 2 does not operate, the low temperature sensing thermistor 23 determines whether or not the antifreeze operation is necessary and releases the antifreeze operation mode in the same manner as described above. (S11
7). As a result, it is possible to perform the antifreezing operation only when necessary, and it is possible to avoid wasting energy.

The present invention is not limited to the above embodiment. In the embodiment, when the hot water supply / hot water generation means 2 is operated during the intermittent halt in the anti-freezing operation mode of the heating / hot water generation means 3, not only the bypass circuit 26 but also the water in the bath bypass circuit 12 is circulated. However, the heating water can be circulated only through the bypass circuit 26.

In the present embodiment, the anti-freezing operation is performed by using the bypass circuit 26. However, a dedicated bypass circuit for circulating water in the heating circuit inside the gas water heater is provided. It can be provided separately from the bypass circuit 26.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a hot water supply / room heater according to the present invention.

FIG. 2 is a block diagram showing connections of various parts in the hot water supply / room heater shown in FIG.

FIG. 3 is a flowchart illustrating an example of an antifreezing operation according to the present invention.

[Explanation of symbols]

 2 Hot water supply hot water generation means 2b Hot water supply side intake fan 3 Heating hot water generation means 3b Heating side intake fan 13a Terminal heater 13b Terminal heater 13c Terminal heater 14 High temperature terminal heating circuit 15a Terminal heater 15b Terminal heater 15c Terminal heater 16 Low temperature side terminal heating circuit 18 Circulation pump 19 High temperature side water temperature detecting means 23 Low temperature sensing thermistor (freezing dangerous temperature detecting means) 25 Central control device (control means) 26 Bypass circuit

Claims (3)

(57) [Claims] 1. Hot water supply hot water generating means and heating hot water generating means for generating hot water using a gas burner, a hot water supply side intake fan attached to each of the hot water generating means and introducing combustion air into these hot water generating means, and a heating unit A side intake fan,
A circulating pump for circulating the hot water generated by the heating hot water generating means to a terminal heater. And the intermittent operation of the heating hot water generating means, the heating side intake fan and the circulation pump to perform an antifreeze operation of the heating circuit including the terminal heater, and in the antifreeze operation mode, the heating hot water When the hot water supply hot water generation means and the hot water supply side intake fan are operated during the intermittent pause of the generation means, the heating side intake fan is operated and the circulation pump is operated to circulate the water of the heating circuit inside the gas hot water supply heating machine. By preventing freezing of the heating circuit inside the gas water heater, Anti-freeze method to kick. 2. A hot water supply hot water generating means and a heating hot water generating means for generating hot water using a gas burner, a hot water supply side intake fan attached to each of the hot water generating means and introducing combustion air into these hot water generating means, and a heating unit. A side intake fan,
A circulation pump that circulates the hot water generated by the heating hot water generating means to the terminal heater through a heating circuit, and a bypass circuit that connects the upstream side and the downstream side of the terminal heater in the heating circuit to each other in the main body. And a freezing dangerous temperature detecting means for detecting that the freezing dangerous temperature has become below the freezing dangerous temperature, wherein the freezing dangerous temperature detecting means detects that the freezing dangerous temperature is below the freezing dangerous temperature. The anti-freezing operation mode is performed by intermittently operating the heating hot water generating means, the heating side intake fan, and the circulation pump to perform the anti-freezing operation of the heating circuit including the terminal heater. In the case where the hot water supply hot water generating means and the hot water supply side intake fan are operated during the intermittent pause of the heating hot water generation means, the heating side intake fan A control means is provided to prevent the freezing of the heating circuit inside the gas water heater by circulating the water of the heating circuit inside the gas water heater by operating the circulation pump through the bypass circuit. An anti-freezing device, characterized in that: 3. The gas hot water supply / room heater configured to exchange information with the terminal heater to perform opening / closing control of a thermal valve or the like of the terminal heater. The anti-freezing device according to claim 2, characterized in that when performing an anti-freezing operation inside the gas hot water heater, opening / closing of a thermal valve or the like is controlled so that hot water is not circulated through the terminal heater.