JP3431990B2 - Heater control method and apparatus for combustion device with freeze prevention 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 heater control method for a combustion device with a freeze prevention heater used for a water heater, a bathtub or the like, and a heater control device therefor.

[0002]

2. Description of the Related Art FIG. 6 shows a conventional indoor water heater as a conventional combustion apparatus, and FIG. 7 shows an outdoor water heater. The indoor water heater has a duct 14 for exhausting exhaust gas to the outside, and the outdoor water heater has a rainwater shelter 15 to prevent rainwater from entering the equipment case 1. There is. These water heaters
A burner 2 and a water pipe heat exchanger 3 are housed in the instrument case 1. A water supply introduction pipe 5 is connected to the inlet side 4 of the heat exchanger 3, the water supply introduction pipe 5 passes through the inside of the instrument case 1, and the water supply introduction end 7 thereof is projected outside the instrument case 1 to a water pipe 19. It is connected. Further, a hot water supply connection pipe 8 is connected to the outlet side 6 of the heat exchanger 3, the hot water supply connection pipe 8 passes through the inside of the instrument case 1, and the discharge end 9 thereof is the instrument case 1.
It is projected to the outside and connected to the hot water supply pipe 18. These water heaters are configured to take in external air from an intake port, perform burner combustion, discharge combustion exhaust gas from the exhaust port 11, and use the heat exchanger 3 to convert running water into hot water to supply hot water to a kitchen, a bathroom, or the like. .

By the way, in cold regions, the water in the water supply introduction pipe 5, the hot water supply connection pipe 8 and the water pipe of the heat exchanger is likely to freeze in the winter, and particularly the water supply introduction end 7 and the hot water discharge end 9 come into contact with the outside air. Since it is easy to freeze at the beginning because it is a part, the equipment case 1 near the water supply introduction end 7 and the hot water supply discharge end 9 which are the coldest
Heater installation areas A and B are provided inside, and on the water supply introduction end 7 side of the heater installation areas A and B, a temperature sensor 10A for measuring the surface temperature, ambient temperature or water temperature of the water supply introduction pipe 5 and a freeze prevention heater 16 On the discharge end 9 side of the hot water supply connection pipe 8, there are provided a temperature sensor 10B for measuring the surface temperature, ambient temperature or water temperature of the hot water supply connection pipe 8 and a freeze prevention heater 16, respectively. When the detected temperature becomes lower than a predetermined lower limit temperature close to the freezing temperature, the freeze prevention heater 16 is turned on to prevent the water heater from freezing.

[0004]

However, in order to prevent freezing of the water supply pipe 19 and the hot water supply pipe 18 connected to the water supply introduction pipe 5 and the hot water supply connection pipe 8, the water supply introduction end 7 and the discharge end 9 of the hot water supply connection pipe 9 are prevented.
In addition to winding a heat insulating material around these pipes in the vicinity of, a heater and a temperature sensor are often attached between the heat insulating material and the water pipe. However, when this heater is heated, the water in the heater is heated and convected, and the water in the heater installation areas A and B in the instrument case 1 is also heated. Since the heater installation areas A and B that should be cooled first do not cool and the operating temperature of the freeze prevention heater 16 does not drop, the freeze prevention heater 16 does not operate. Therefore, the temperature of the heater installation regions A and B is
There was a problem that the easily cooled portions other than the heater installation regions A and B were frozen before the temperature decreased to the operating temperature.

Further, particularly in the case of windy conditions, in the indoor water heater shown in FIG. 6, a back wind stop gap (not shown) is sewn to cool air from the exhaust port 11 as the cold air blowing portion 13 in the direction of arrow E. Corresponds to the central area C on the upper surface of the heat exchanger 3,
The detected temperatures of the temperature sensor 10A on the side of the water supply introduction end 7 of the water supply introduction pipe 5 and the temperature sensor 10B on the side of the discharge end of the hot water supply connection pipe are
There is a problem that the area C is cooled by the cool air before the heater operation temperature is lowered, and the water pipe 20C in the area C is frozen. In the outdoor water heater shown in FIG. , Cold wind in the direction of arrow F hits the D area on the upper surface of the heat exchanger 3, and the water pipe 20D in this D area
There was a problem that it was cooled and frozen.

In order to solve such a problem, the applicant of the present invention, in the case of an indoor water heater, as shown in FIG. 4, has a water pipe 20C (heat exchanger) passing through a region C exposed to cold air. Temperature sensor on the water pipe 20C exposed from 3)
10C is provided, and in the case of an outdoor-installed water heater, the temperature sensor 10 is also provided in the portion of the water pipe 20D that passes through the region D where cold air strikes (the portion of the water pipe 20D exposed to the outside from the heat exchanger 3).
C is provided, and even if any one of the temperature sensors 10A, 10B, and 10C becomes lower than or equal to a preset lower limit set temperature (for example, 2 ° C.), all the freeze prevention heaters 16 are turned on, When all the temperature sensors 10A, 10B, 10C reach or exceed the preset heater stop temperature, the freeze prevention heater 16 is drive-controlled so that the heating drive of the freeze prevention heater 16 is turned off, so that the water pipe in the water heater can be reliably operated. We propose a method to achieve freeze prevention. In addition, in the water heaters of these proposed examples, a freeze prevention heater 16 is additionally provided on the body of the water tube heat exchanger 3.

By the way, the heater driving control system for the water heaters of the conventional example and the proposed example are all temperature sensors for preventing freeze.
Since 10A, 10B, and 10C are controlled on the assumption that no failure will occur, even if one of them fails when the temperature sensor has the heater on, the heater remains on and the heater remains off. If it fails, the heater will remain off.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a freezing prevention heater correctly even if a defective temperature sensor is generated among a plurality of freezing prevention temperature sensors. It is an object of the present invention to provide a heater control method for a combustion device with a freeze prevention heater and a device therefor capable of performing on / off driving of the above.

[0009]

In order to achieve the above object of the present invention, it is constructed as follows. That is , the first invention of the heater control method includes a plurality of freeze prevention heaters.
It is installed in different places of the combustion device, and temperature sensors are provided in a plurality of different places in the combustion device.When the temperature detection signal value of each temperature sensor is out of the normal determination range given in advance, it is determined that the sensor is defective, and the sensor When the detected temperature of each normal temperature sensor is monitored by excluding the signal of the temperature sensor that is determined to be defective, and the detected temperature of at least one of the monitored temperature sensors falls below a preset lower limit temperature.
All the anti-freezing heaters are turned on, and when the temperature detected by all the sensors of the monitor temperature sensor is equal to or higher than a preset heater stop temperature, the heating drive of all the anti-freezing heaters is turned off. It is configured.
A second invention of a heater control method is the heater control.
In a device with the first inventive arrangement of the method,
The equipment is equipped with a water pipe heat exchanger for hot water supply.
Pass the water pipe through the part of the exchanger where the cold air hits, and hit this cold air
The water pipe that passes through the part is exposed to the water pipe heat exchanger.
Along with the temperature sensor,
The exposed water pipe is connected to an external hot water supply pipe.
As the water pipe heat exchanger,
The temperature provided on the exposed part of the water pipe that passes through the part where the cold air of the exchanger hits.
Temperature sensor to drive antifreeze heaters multiple temperatures
It is characterized in that it is one of the sensors.

Further, the first invention of the Heater controller, different
In a heater control device of a combustion device with a freeze prevention heater, which is provided with a plurality of freeze prevention heaters installed in different locations and a temperature sensor installed in a plurality of different locations,
Taking in the temperature detection signal of each of the plurality of temperature sensors, comparing each temperature detection signal value and the normal judgment range of the signal value given in advance, the temperature detection signal value is out of the normal judgment range and the temperature sensor is defective. A defective sensor signal excluding means for judging and excluding the temperature detection signal of the defective temperature sensor, and a detected temperature of a normal temperature sensor not excluded by the defective sensor signal excluding means are monitored, and at least one sensor of the monitored temperature sensors is monitored. When the detected temperature falls below the preset lower limit temperature, all the freeze prevention heaters are commanded to turn on,
Heater drive control means for instructing to turn off the heating drive of all the freeze prevention heaters when the temperature detected by all of the monitor temperature sensors is equal to or higher than a preset heater stop temperature, and the heater drive A heater driving means for driving the freeze prevention heater on / off in response to a command from the control means is provided. Also, heater system
A second invention of the control device is the first invention of the heater control device.
Combustion devices provide hot water supply for those with a bright configuration
Equipped with a water pipe heat exchanger, the cold air of this water pipe heat exchanger
Water that passes through the water pipe through the barrel and this cold wind
Install a temperature sensor on the exposed part of the tube that comes out of the water tube heat exchanger.
Water on the exposed part where the temperature sensor is installed
The pipe is the water pipe as a hot water supply connection pipe that connects to an external hot water supply pipe.
Out of the water heat exchanger and cool air from the water pipe heat exchanger
Freezing the temperature sensor provided on the exposed part of the water pipe that passes through the barrel
Of the multiple temperature sensors for driving the preventive heater
It is characterized by having one.

[0011]

In the present invention having the above-mentioned structure, the heating drive of the freeze prevention heater is controlled by monitoring the temperature detection signals of a plurality of temperature sensors installed in the combustion device. In this heater control, when a defective temperature sensor among the plurality of temperature sensors occurs, the temperature detection signal value of the temperature sensor is out of the normal determination range given in advance. The temperature sensor of the specified value is judged as a sensor failure, the signal of the temperature sensor judged to be defective is excluded, the temperature detection signals of the remaining normal temperature sensors are monitored, and the lower limit temperature is set even for one of the monitored temperature sensors. When the temperature falls below, all the freeze prevention heaters are turned on, and when all the detected temperatures of the monitor temperature sensor exceed the heater stop temperature, the heating drive of all the freeze prevention heaters is turned off. Even if a failure occurs in the temperature sensor for the vehicle, normal on / off drive control of the freeze prevention heater can be achieved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In the description of the present embodiment, the same reference numerals will be given to the same names as those in the conventional example and the proposed example, and the duplicated description will be omitted. FIG. 1 shows a schematic diagram of the main part configuration of an embodiment of a combustion apparatus according to the present invention. In the present embodiment, as in the conventional example and the proposed example, as the combustion device, an indoor installation type or an outdoor installation type water heater with an antifreezing heater for supplying hot water to a kitchen, a bathroom, etc. is targeted. As a typical example of the water heater, an outdoor type water heater similar to that shown in FIG. 7 is shown.

In the water heater of this embodiment, similar to the proposed example,
A portion of the water pipe 20D that passes through the vicinity of the water supply introduction end 7, the vicinity of the discharge end 9, and the portion D of the water pipe heat exchanger 3 where the cold air hits.
(See FIG. 5) The temperature sensors 10A, 10 such as thermistors
B and 10C are installed respectively, and a freezing prevention heater 16 is provided in each of the basin A near the feed water introduction end 7, the area B near the discharge end 9, and the area of the body of the water pipe heat exchanger 3. The heater controller 21 controls the freeze prevention heater 16
ON / OFF drive of is controlled.

FIG. 2 shows a block configuration of the heater control device 21. The heater control device 21 includes a defective sensor signal excluding means 25, a heater driving control means 23 for commanding heater driving, a heater driving means 26, and a memory 2.
It has 4 and 27. Memory 24 is for each temperature sensor 10A
A temperature range (a range of temperature detection signal values) detected (or expected to be detected) by 10C is stored as a normal determination range. For example, a temperature detection signal value range in the temperature range of −5 ° C. to 80 ° C. is given and stored.

The defective sensor signal excluding means 25 compares the temperature detection signal value of each of the temperature sensors 10A to 10C with the normal determination range stored in the memory 24, and the signal value of the detected temperature of each of the temperature sensors 10A to 10C is determined. When the temperature sensor is out of the normal determination range, the temperature sensor outside the normal determination range is determined to be defective, and the output of the temperature detection signal of the defective temperature sensor is excluded.

The memory 27 is provided with a lower limit set temperature as a reference for turning on the heater 16 as a value of, for example, 2 ° C., and a heater stop temperature as a reference for stopping the heater as a value of, for example, 7 ° C. It is given and remembered. The heater drive control means 23 includes a detected temperature comparison / determination section 22, and the temperature detection signal value of each normal temperature sensor not excluded by the defective sensor signal exclusion means 25 and the lower limit set temperature and heater stored in the memory 27. When it detects that even one of the temperature detection signal values of each normal temperature sensor is below the lower limit set temperature by comparing with the stop temperature, it outputs a heater drive command and outputs all the detected temperatures of normal temperature sensors. When the signal value exceeds the heater stop temperature, the heater stop command is output.

The heater drive means 26 is a heater drive control means.
When a heater drive command is applied from 23, all the heaters 16 are turned on, and when a heater drive stop command is received from the heater drive control means 23, all the heaters 16 are collectively turned off.

FIG. 3 shows a flow chart of heater control of the water heater of this embodiment. Next, the heater drive control operation will be described based on this flow chart. First, in step 101, the defective sensor signal excluding means 25 determines whether or not each of the temperature sensors 10A, 10B and 10C is normal,
The temperature detection signal value of each temperature sensor is compared with the normal determination range. When the temperature detection signal value of the temperature sensor is within the normal determination range, it is determined to be normal, and when it is out of the normal determination range, it is determined to be defective. .

In step 101, all the temperature sensors 10A-10
When C is determined to be normal, it is then determined in step 102 whether all the temperatures detected by the temperature sensors 10A to 10C are 7 ° C. or higher, which is the heater stop temperature. All temperature sensors 10
When the detected temperature of A to 10C is 7 ℃ or higher,
In step 105, all the heaters 16 are turned off. On the other hand, when all the detected temperatures of the temperature sensors 10A to 10C have not reached the heater stop temperature of 7 ° C., step 10
At 3, it is determined whether or not any one of the temperature sensors 10A to 10C is below the lower limit set temperature of 2 ° C. When the temperature detected by all temperature sensors 10A-10C is higher than 2 ℃,
That is, when the temperature is higher than 2 ° C. and lower than 7 ° C., the operations after step 101 are repeated.

On the other hand, in step 103, the temperature sensors 10A ...
When any one of the 10C has become lower than the lower limit temperature of 2 ° C., all the heaters 16 are turned on in step 104 to prevent the water tubes from freezing.

In step 101, all temperature sensors 10A
If it is judged that the condition that the temperature range of 10C is normal is not satisfied, then in step 106, the temperature sensor 10 is detected.
It is determined whether all of A to 10C are abnormal (defective). If all the temperature sensors 10A to 10C are defective, at step 110, all the heaters 16 are driven off.

When there is at least one normal temperature sensor (non-defective temperature sensor) among the temperature sensors 10A to 10C, the heater 16 is driven and controlled using the temperature detection signal value of the normal temperature sensor. That is, in step 107, all the detected temperatures of the normal temperature sensor are equal to the heater stop temperature 7
It is determined whether or not the temperature is above ℃, and when all the detected temperatures of the normal temperature sensor are above 7 ℃, all the heaters 16 are driven off in step 110.

When all the temperatures detected by the normal temperature sensor have not reached 7 ° C., at step 108, any one of the temperatures detected by the normal temperature sensor is set to the lower limit setting temperature 2
It is determined whether or not there is a temperature of less than or equal to ℃, and even if there is at least one temperature sensor that detects a temperature of less than or equal to 2 ℃, all the heaters 16 are turned on to prevent freezing of the water pipe. When any of the normal temperature sensors detects a temperature higher than 2 ° C., the operation returns to the first step 101.

In the present embodiment, the temperature sensor 10A provided at the position of the water supply introduction end 7 side of the water supply introduction pipe 5, the temperature sensor 10B provided at the position of the discharge end 9 side of the hot water supply connection pipe 8 and the heat of the area exposed to cold air When even one of the temperature sensors 10C provided at the position of the outer exposed portion of the water pipe passing through the exchanger is below the lower limit set temperature (2 ° C), all the freeze prevention heaters 16 are turned on. Driven and all temperature sensors
When the detected temperature of 10A to 10C becomes equal to or higher than the heater stop temperature (7 ° C), the heating drive of all the freeze prevention heaters 16 is turned off.
In order to prevent freezing of the hot water supply pipe 19 and the hot water supply pipe 18, a heater is attached near the hot water supply end 7 and the hot water discharge end 9, and when this heater is turned on, the outside air cools and the outside air falls below the freezing temperature. When this happens, the heater 16 is not turned on because the temperature sensors 10A and 10B detect a temperature sufficiently higher than the outside air due to the heating of the heater, and conventionally there is a problem that portions other than the heater installation areas A and B freeze. However, in the present embodiment, the temperature detected by the temperature sensor 10C provided at the position of the water pipe 20D passing through the region D exposed to the cold air is the lower limit set temperature (2
When the temperature falls below (° C.), all the freeze prevention heaters 16 are turned on, and the freeze prevention of the water heater is ensured.

Further, in the case of a windy condition, conventionally, the water pipe 20D passing through the region D exposed to the cold air freezes before the temperature detected by the temperature sensors 10A and 10B decreases to the heater operating temperature (lower limit set temperature). However, in the present embodiment, when the temperature detected by the temperature sensor 10C provided at the position of the water pipe passing through the region D exposed to cold air is below the lower limit set temperature, all the freeze prevention heaters 16 are turned on. Therefore, it is possible to prevent the water heater from freezing.

Further, in this embodiment, the defective sensor signal excluding means 25 is provided, and among the plurality of temperature sensors 10A to 10C,
Since it is configured to detect a defective temperature sensor and exclude the temperature detection signal of the defective temperature sensor,
Since the defective temperature sensor is excluded and the driving control of the heater 16 is performed only based on the signal of the normal temperature sensor, the ambient temperature does not reach the lower limit set temperature due to the signal output of the defective temperature sensor. However, the problem of malfunction of the heater driving in which the heater 16 is continuously driven even though the heater 16 is driven on or the ambient temperature is higher than the heater stop temperature is effectively solved. The heater drive control can be performed accurately and with high reliability.

The present invention is not limited to the above-mentioned embodiment, and various embodiments can be adopted. That is, although the thermistor is used as the temperature sensor in the above embodiment, it may be one whose electric resistance changes depending on temperature, or switches such as bimetal.

Further, in the above embodiment, the temperature sensor 10C is provided in the freezing area on the heat exchanger side where the cold air from the exhaust port side hits. However, for example, an intake hole of a fan (not shown) or another cold air hit area. In addition, a temperature sensor may be provided. Also,
The number of temperature sensors is not limited to three (10A to 10C), and the required number of temperature sensors can be provided at any position that is considered necessary for freezing prevention.

Further, in the above embodiment, the lower limit set temperature is set to 2 ° C. to prevent freezing, but it may be set to 3 ° C. and the heater stop temperature is set to 7 ° C., but 6 ° C. or 8 ° C. The temperature may be set according to the actual condition.

Furthermore, in the above embodiment, the temperature sensor and the freeze prevention heater are provided at the position of the water supply introduction end side, the hot water supply connection pipe discharge end side, and the outer exposed portion of the water pipe passing through the heat exchanger. An antifreezing heater may be appropriately added and provided at a position where water easily accumulates or a position where water easily cools. In addition, since tap water does not freeze unless the inside of the equipment case falls below the freezing temperature, temperature sensors and freeze prevention heaters are installed in equipment cases other than the water supply introduction pipe, hot water supply connection pipe, water pipe of heat exchanger, etc. Then, even if the detected temperature of air in the equipment case becomes lower than the lower limit set temperature even at one place, the antifreezing heater is turned on to raise the temperature of the air and prevent freezing of water. Good.

Further, in the above-mentioned embodiment, the outdoor type water heater is explained as an example, but the present invention is similarly applied to the indoor type water heater as shown in FIG. 4, for example. Is.

Further, in the above embodiment, the water pipe 20D is passed through the region of the water pipe type heat exchanger 3 where the cold air hits, but also in the water heater of the type where the water pipe is not necessarily passed through the region of the heat exchanger 3 where the cold air hits. The present invention is applied.

Furthermore, in the above embodiment, the water heater was explained as the combustion device, but the heater control method and device for preventing freezing of the present invention are applied to various other combustion devices such as bathtubs and heaters. can do.

[0034]

According to the present invention, a combustion apparatus is provided with a plurality of freeze prevention heaters and a plurality of temperature sensors, and at least one of the plurality of temperature sensors has a lower limit set in advance by a temperature detected by at least one normal sensor. When the temperature falls below the temperature, all antifreeze heaters are turned on, and when the temperature detected by all normal temperature sensors exceeds the heater stop temperature, all antifreeze heaters are turned off. Since it is configured to do so, when the ambient temperature becomes close to freezing, the heating drive of the heater is immediately performed,
It is possible to reliably prevent freezing of the water pipe of the combustion device.

Further, according to the present invention, among the plurality of installed temperature sensors, the temperature sensor whose temperature detection signal value is out of the predetermined normal judgment range is determined to be defective, and the temperature detection signal of the defective temperature sensor is excluded. Since the heater drive control is performed using only the temperature detection signal of the normal temperature sensor, the temperature inside the combustion device is affected by the signal from the defective temperature sensor, and It is possible to reliably prevent the malfunction of the heater driving in which the heating driving of the heater is not stopped even if the heater is not driven to heat even if the temperature becomes the following or even if the temperature inside the combustion device is higher than the heater stop temperature. Therefore, the freezing prevention operation of the heater can be performed accurately and with high reliability.

[Brief description of drawings]

FIG. 1 is a structural explanatory view of a water heater with a freeze prevention heater according to an embodiment of the present invention.

FIG. 2 is a block configuration diagram of a heater control device provided in the water heater of the embodiment.

FIG. 3 is a flowchart showing an operation of heater control according to the present embodiment.

FIG. 4 is a perspective view illustrating the indoor water heater with a freeze prevention heater proposed by the applicant.

FIG. 5 is an explanatory perspective view of a water heater with an antifreeze heater of an outdoor type, which is also proposed by the applicant.

FIG. 6 is an explanatory view of a conventional indoor water heater.

FIG. 7 is an explanatory view of a conventional outdoor water heater.

[Explanation of symbols]

10A, 10B, 10C temperature sensor 16 Freezing prevention heater 21 Heater controller 22 Detection temperature comparison judgment unit 23 Heater drive control means 25 Defective sensor signal exclusion means 26 Heater driving means

Claims (4)

(57) [Claims] 1. A plurality of freeze prevention heaters are provided in different combustion devices.
The temperature sensor is installed at multiple different locations inside the combustion device, and if the temperature detection signal value of each temperature sensor is out of the normal judgment range given in advance, it is judged as a sensor failure, and it is judged as a sensor failure. The detected temperature of each normal temperature sensor is monitored by excluding the signal of the temperature sensor that has been operated, and when the detected temperature of at least one sensor of the monitored temperature sensor falls below the preset lower limit set temperature, the entire temperature is frozen. In a combustion device with a freeze prevention heater, which drives the prevention heater on and turns off the heating drive of all the freeze prevention heaters when the temperature detected by all the sensors of the monitor temperature sensor is equal to or higher than a preset heater stop temperature. Heater control method. 2. A water pipe type heat exchanger for supplying hot water is used as the combustion device.
Prepare and install a water pipe in the part of this water pipe heat exchanger where cold air hits.
The water pipe that passes through this cold wind hits the water pipe heat exchange.
Install a temperature sensor on the exposed part of the container and
The exposed water pipe with the temperature sensor is an external hot water supply pipe
As a hot water supply connection pipe to be connected to the
Water that passes through the part of the water pipe heat exchanger that is exposed to the cold air.
Drive the freeze prevention heater with the temperature sensor provided on the exposed part of the tube
To be one of the multiple temperature sensors for
A combustion device with a freeze prevention heater according to claim 1,
Heater control method. 3. A heater control device for a combustion device with freeze prevention heater, comprising: a plurality of freeze prevention heaters installed at different places; and temperature sensors installed at a plurality of different places. The temperature detection signal of the temperature sensor is taken in, and each temperature detection signal value is compared with the normal judgment range of the signal value given in advance, and the temperature detection signal value is out of the normal judgment range. The defective sensor signal excluding means for excluding the temperature detection signal of the temperature sensor and the detected temperature of the normal temperature sensor not excluded by the defective sensor signal excluding means are monitored, and the detected temperature of at least one sensor of the monitor temperature sensor is preset. all freeze prevention heater when it is below the lower limit set temperature given to on-command, the detected temperature is previously set for all of the sensors of the monitoring temperature sensor And a heater driving control means for OFF command the heating operation of the freezing prevention heater of the total when a heater stop temperature greater than or equal to, the heater drive to drive on and off the freezing prevention heater according to a command of the heater drive control means And a heater control device for a combustion device with a freeze prevention heater. 4. A water pipe type heat exchanger for supplying hot water is used as the combustion device.
Prepare and install a water pipe in the part of this water pipe heat exchanger where cold air hits.
The water pipe that passes through this cold wind hits the water pipe heat exchange.
Install a temperature sensor on the exposed part of the container and
The exposed water pipe with the temperature sensor is an external hot water supply pipe
As a hot water supply connection pipe to be connected to the
Water that passes through the part of the water pipe heat exchanger that is exposed to the cold air.
Drive the freeze prevention heater with the temperature sensor provided on the exposed part of the tube
To be one of the multiple temperature sensors for
A combustion device with a freeze prevention heater according to claim 4,
Heater control device.