JP4155404B2 - Heat exchanger unit - Google Patents

Description

  The present invention relates to a heat exchanger unit that performs heat exchange between hot water flowing through a primary side circulation circuit including a heat source device and hot water flowing through a secondary side circulation circuit including a heat radiating device.

  Conventionally, liquid-liquid heat exchange between a primary side circulation circuit including a heat source device, a secondary side circulation circuit including a heat radiating device, and hot water flowing through the primary side circulation circuit and hot water flowing through the secondary side circulation circuit. There is known a hot water heating system including a heat exchange unit for performing (see, for example, Patent Document 1). In this hot water heating system, hot water is generated by the heat source device, and the generated hot water is circulated through the primary side hot water circulation circuit, and hot water (water when the temperature is low) is circulated through the secondary side circulation circuit for heat exchange. In the unit, heat is exchanged between the hot water in the primary side circulation circuit and the hot water in the secondary side circulation circuit, and the hot water heated by the heat exchange is supplied to the heat radiating device, and is radiated in this heat radiating device to the indoor space. Is heated.

  In such a hot water heating system, when perforation occurs in the exchanger body of the heat exchange unit, the hot water flowing through the primary circuit circulates through the hole where it is generated and flows into the secondary circuit, and when the amount of inflow increases, There is a risk that the hot water temperature in the secondary circulation circuit will rise abnormally and the surface temperature of the heat radiating equipment will increase, or the amount of hot water flowing through the secondary circulation circuit will be excessively large and part of it will be damaged or damaged. For this reason, a detection mechanism for detecting perforations in the exchanger body is provided. In this hot water heating system, the secondary side circulation circuit is composed of a semi-hermetic circuit, and the secondary side circulation circuit is provided with a hot water tank serving as a reservoir of hot water and a drain tank connected to the hot water tank. A water level detector is provided in connection with the tank.

  In this hot water heating system, when a hole is generated in the exchanger body of the heat exchange unit and the hot water in the primary side circulation circuit is generated and flows into the secondary side circulation circuit, a part of the hot water in the secondary side circulation circuit is obtained. Flows into the drain tank through the hot water tank, and the water level of the drain tank rises from the normal level. Then, when the water level rises to an abnormal level due to the inflow of hot water, the water level detector detects the raised water level, and the detection of this water level indicates that a malfunction (ie, perforation) has occurred in the heat exchange unit. Can be detected.

JP-A-5-118567

  In the hot water heating system described above, since the secondary circulation circuit is a semi-sealed circuit, the detection mechanism having the above-described configuration can be employed. However, such a semi-sealed circuit (of course in an open circuit) operates. In the hot water heating system, hot water containing dissolved oxygen circulates in the secondary side circulation circuit. Therefore, when using heat sinks and hot water pipes made of iron, etc., there is a problem that the iron heat sinks and hot water pipes are corroded by the dissolved oxygen, which makes it difficult to rust the heat sinks and hot water pipes. There is a problem that it is necessary to form the material from an expensive material, which increases the manufacturing cost of the hot water heating system.

  Thus, there is also known one in which the secondary circuit of the hot water heating system is a sealed circuit. In this hot water heating system, the hot water circulating in the secondary side circulation circuit contains almost no oxygen. Therefore, it is possible to remarkably suppress the occurrence of rust in heat dissipation equipment, hot water piping, etc., and cheap iron is used as these materials. The manufacturing cost of the hot water heating system can be reduced.

  However, in the hot water heating system in which the secondary circuit is closed, the detection mechanism (semi-hermetic detection mechanism) described above cannot be used to detect the occurrence of perforation in the heat exchange unit. If such a detection mechanism is employed, the sealed structure of the secondary side circulation circuit cannot be maintained.

  An object of the present invention is to provide a heat exchanger unit capable of detecting perforations in the exchanger body while maintaining a sealed structure of the secondary side circulation circuit.

The heat exchanger unit according to claim 1 of the present invention is a heat which performs heat exchange between the hot water flowing in the primary side circulation circuit including the heat source unit and the hot water flowing in the secondary side circulation circuit including the heat radiating device in the exchanger body. An exchange unit,
The primary side circulation circuit is composed of an open circuit that is open to the atmosphere, the secondary side circulation circuit is composed of a sealed circuit that is sealed, and the primary side circulation circuit includes hot water that flows through the primary side circulation circuit. An input calorie measuring means for measuring the input calorie input is provided, and the secondary side circulation circuit has an output for measuring the output calorie output to the hot water flowing through the secondary side circulation circuit. A heat quantity measuring means is provided, and the perforation of the exchanger body is detected on the basis of the heat quantity measured by the input heat quantity measuring means and the output heat quantity measuring means.

According to the heat exchanger unit according to claim 1 of the present invention , the heat exchange is performed between the hot water flowing in the primary side circulation circuit and the hot water flowing in the secondary side circulation circuit, and the heat exchange is performed. In order to detect perforation in the main body, an input heat amount measuring means is provided in the primary side circulation circuit, and an output heat amount measuring means is provided in the secondary side circulation circuit. When a malfunction occurs in the exchanger body of the heat exchanger unit (for example, a hole in the exchanger body), hot water heated by the heat source device (for example, about 80 ° C.) flows through the exchanger body. It flows into the secondary circulation circuit through the generated hole. When the warm water of the primary side circulation circuit flows into the secondary side circulation circuit in this way, the ratio of the output heat quantity to the input heat quantity becomes larger than when heat exchange is normally performed, and the ratio of this transferred heat quantity is measured. Therefore, it is possible to detect the occurrence of a defect, for example, perforation, in the exchanger main body, and it is possible to detect the secondary side circulation circuit in a sealed state.

When no trouble occurs in the exchanger body, 85 to 95% of the heat input from the hot water in the primary circuit is transferred to the hot water in the secondary circuit as output heat. If a malfunction (for example, perforation) occurs in the main body of the vessel, the heat amount of 96% or more of the input heat amount is transferred to the hot water of the secondary side circulation circuit as the output heat amount due to the inflow of hot water from the primary side circulation circuit. Thus, when the abnormal transmission ratio is set to about 97%, for example, when the ratio of the measured output heat quantity of the output calorie measuring means to the measured input heat quantity of the input calorie measuring means reaches this abnormal transmission ratio, this abnormal transmission ratio The occurrence of a malfunction in the heat exchanger section can be detected at the time when the temperature reaches the value.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of a heat exchanger unit for carrying out the invention will be described with reference to the accompanying drawings.
[First Embodiment]
First, with reference to FIG. 1, the heat exchanger unit of 1st Embodiment is demonstrated. FIG. 1 is a simplified diagram schematically illustrating an example of a hot water heating system including a heat exchanger unit according to the first embodiment.

  In FIG. 1, this hot water heating system includes a primary side circulation circuit 2 for generating and circulating hot water, a secondary side circulation circuit 4 for circulating and radiating warmed hot water, and a primary side circulation. A heat exchanger unit 6 that performs heat exchange between the hot water flowing through the circuit 2 and the hot water flowing through the secondary side circulation circuit 4 is provided.

  The primary-side circulation circuit 2 includes a heat source unit 8 for generating hot water, and a primary-side circulation channel 10 for circulating hot water through the heat source unit 8 and the heat exchanger unit 6, and this primary-side circulation channel. A primary side feed pump 12 is disposed at 10. When the heat source unit 8 and the primary side feed pump 12 are operated, the hot water generated in the heat source unit 8 is circulated through the heat exchanger unit 6 through the primary side circulation channel 10 as indicated by an arrow. Note that the heat source unit 8 may be, for example, one that generates hot water by burning fuel gas, fuel oil, or the like.

  Further, the secondary side circulation circuit 4 includes a heat radiating device 14 for radiating heat of the hot water, and a secondary side circulation channel 16 for circulating the hot water through the heat radiating device 14 and the heat exchanger unit 6. A secondary side feed pump 18 is disposed in the secondary side circulation passage 16. The secondary circulation channel 16 is further provided with a thermal valve 20 and a thermo valve 22, and a bypass channel 24 is connected to bypass the thermal valve 20, the thermo valve 22 and the heat dissipation device 14. Yes. When the secondary side feed pump 18 operates, the hot water is circulated through the heat exchanger unit 6 through the secondary side circulation passage 16. When the thermal valve 20 and / or the thermo valve 22 are closed, the hot water in the secondary side circulation circuit 4 passes through a part of the secondary side circulation channel 16 and the bypass channel 24 and passes through the heat exchanger unit 6. It is circulated and overheating due to idling of the secondary side feed pump 18 is prevented. The thermal valve 20 is opened and closed by the operation (ON) and the operation stop (OFF) of the heat dissipating device 14, and the thermo valve 22 is controlled to open and close at room temperature. The heat radiating device 14 may be, for example, a heat radiating panel or a heat radiating tube.

  In this embodiment, the primary side circulation circuit 2 is an open circuit opened to the atmosphere, and the primary side circulation flow path 10 is opened to the atmosphere in the heat source unit 8. On the other hand, the secondary circulation circuit 4 is a sealed circuit that is not opened to the atmosphere, and air in the atmosphere is not mixed into the hot water of the secondary circulation path 16. Accordingly, there is almost no corrosion in the secondary side circulation circuit 4, and it becomes possible to form the piping defining the secondary side circulation flow path 16, the heat dissipation device 14, etc. with an inexpensive material such as iron, It can be used for a long time.

  In connection with the secondary side circulation circuit 4 being a sealed circuit, the secondary side circulation channel 16 is further provided with an overpressure relief valve 26 and an expansion tank 28. The overpressure relief valve 26 is opened when the pressure in the secondary circulation passage 16 exceeds the set abnormal pressure value, and the pressure is released to the outside. As a result, the pressure in the secondary circulation passage 16 is abnormal. To prevent it from rising. Further, the expansion tank 28 is communicated with the secondary side circulation channel 16, and when the volume of the warm water increases due to the temperature rise, a part of the warm water in the secondary side circulation channel 16 flows in, and the temperature falls due to the temperature fall. When the volume decreases, the hot water in the expansion tank 18 flows out to the secondary circulation passage 16 and thus absorbs the volume change of the hot water accompanying the temperature fluctuation.

  The heat exchanger unit 6 includes an exchanger body 30 for exchanging heat between the hot water in the primary-side circulation circuit 2 and the hot water in the secondary-side circulation circuit 4, and in this embodiment, the secondary-side circulation channel 16 is provided. The flowing hot water flows in the heat exchange tube 32 provided in the exchanger main body 30, and the hot water flowing in the primary side circulation channel 10 flows outside the heat exchange tube 32 in the exchanger main body 30, and the heat exchange tube Heat exchange between the hot water of the primary side circulation circuit 2 and the hot water of the secondary side circulation circuit 4 is performed via 32, and the hot water of the secondary side circulation passage 16 is heated by this heat exchange.

In such a hot water heating system is configured as the hot water delivery pressure flowing through the primary side circulation flow path 10 is larger than the hot water delivery pressure of the secondary circulation flow path 16. With this configuration, when perforation occurs due to corrosion or the like, for example, in the heat exchange tube 32 of the exchanger body 30 of the heat exchanger unit 6, the hot water flowing through the primary side circulation passage 10 becomes the secondary side circulation flow. It is configured as follows so as to detect the inflow of the hot water of the primary side circulation circuit 2 to the secondary side circulation passage 16 due to such perforations.

  The heat exchanger unit 6 includes a temperature sensor 34 (which constitutes temperature detection means) for detecting the temperature of the hot water, and this temperature sensor 34 is connected to the secondary-side circulation channel 16 (specifically, the bypass channel). 24 downstream of the connection site). The temperature sensor 34 detects the temperature of hot water supplied to the heat radiating device 14 through the secondary-side circulation flow path 16.

Next, heating operation of the hot water heating system including the heat exchanger unit 6 and operation stop due to occurrence of a failure will be described. During the heating operation, in the primary side circulation circuit 2, the heat source unit 8 and the primary side feed pump 12 are operated, and hot water of about 80 ° C. generated in the heat source unit 8 is circulated through the primary side circulation channel 10. Further, in the secondary side circulation circuit 4, the secondary side feed pump 18 and the thermal valve 20 are operated, the thermal valve 20 and the thermo valve 22 are opened, and the hot water is supplied to the secondary side circulation channel 16. And circulated through the heat dissipation device 14. Since it is circulated in this way, in the exchanger body 30 of the heat exchanger unit 6, heat exchange is performed between the hot water flowing through the primary-side circulation flow path 10 and the hot water flowing through the secondary-side circulation flow path 16, For example, warm water heated to about 70 to 74 ° C. is supplied to the heat radiating device 14 through the secondary-side circulation channel 16, and the indoor space is heated by heat radiation in the heat radiating device 14 .

  If a malfunction occurs in the exchanger body 30 during such a heating operation (for example, a hole in the heat exchange tube 32), the secondary side circulation flow passes through a hole in which a part of the hot water flowing through the primary side circulation passage 10 is opened. It flows into the path 16. When the warm water flows in this way, the temperature of the warm water in the secondary side circulation channel 16 rises, and as the amount of the inflow increases, the temperature rise increases and approaches the temperature of the warm water flowing through the primary side circulation channel 10. Become. The temperature sensor 34 detects the temperature of the hot water in the secondary circulation path 16, and the temperature of the secondary circulation path 16 warm water is maintained at, for example, about 70 to 74 ° C. in a state where there is no hole. In the state where there is a hole, since the warm water of the primary side circulation channel 10 flows in, the temperature rises and becomes about 75 to 79 ° C., for example. For this reason, this embodiment is configured such that an abnormal signal is generated when the temperature of the hot water in the secondary side circulation passage 16 rises to, for example, 76 ° C. Accordingly, when the temperature detected by the temperature sensor 34 rises to 76 ° C. due to the inflow of hot water from the primary side circulation passage 10, an abnormal signal is generated, and this abnormal signal causes a malfunction (for example, perforation) in the exchanger body 30. The occurrence can be detected. When an abnormal signal is generated, based on the abnormal signal, the primary side circulation circuit 2 (the heat source unit 8 and the primary side feed pump 8) and the secondary side circulation circuit 4 (the secondary side feed pump 18 and The operation of the thermal valve 20) is stopped.

[Second Embodiment]
Next, with reference to FIG.2 and FIG.3, the heat exchanger unit of 2nd Embodiment is demonstrated. FIG. 2 is a diagram schematically illustrating another example of the hot water heating system including the heat exchanger unit of the second embodiment, and FIG. 3 simply illustrates a control system of the hot water heating system in FIG. 2. It is a block diagram. Note that in the second embodiment, substantially the same members as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  In FIG. 2, in the heat exchanger unit 6 </ b> A of the second embodiment, a change in the ratio of the output heat quantity of the hot water in the secondary circulation path 16 to the input heat quantity of the warm water in the primary circulation path 10 is used. Thus, a malfunction (for example, perforation) of the exchanger main body 30 is detected. More specifically, the primary side circulation passage 10 is provided with an input heat amount measuring means 52 for measuring the input heat amount. The illustrated input calorie measuring means 52 includes a first temperature sensor 54 disposed on the upstream side of the exchanger body 30 in the primary side circulation passage 10 and a second temperature disposed on the downstream side of the exchanger body 30. The sensor 56 includes a first flow rate sensor 58 disposed on the downstream side of the exchanger main body 30. Note that the first flow rate sensor 58 may be disposed on the upstream side of the exchanger body 30 in the primary-side circulation flow path 10.

  In addition, an output heat quantity measuring means 60 for measuring the output heat quantity is provided in the secondary side circulation passage 16. The illustrated output calorie measuring means 60 includes a third temperature sensor 62 disposed on the upstream side of the exchanger body 30 in the secondary circulation passage 16 and a first temperature sensor disposed on the downstream side of the exchanger body 30. 4 temperature sensor 64 (specifically, downstream from the connection part of bypass flow path 24) and second flow rate sensor 66 arranged on the upstream side of exchanger body 30. Note that the second flow sensor 66 may be disposed on the downstream side of the exchanger main body 30 in the secondary circulation passage 16.

  This hot water heating system is controlled by the control system shown in FIG. Referring also to FIG. 3, the hot water heating system further includes a controller 68 for controlling the system. The controller 68 is composed of, for example, a control microprocessor, and includes an input heat amount calculation means 70, an output heat amount calculation means 72, an output ratio calculation means 73, an abnormality determination means 74, an abnormality signal generation means 76, and a memory 78. . Detection signals from the input heat quantity measuring means 52 and the output heat quantity measuring means 60 are sent to the controller 68, and the input heat quantity calculating means 70 calculates the input heat quantity based on the detection signals from the input heat quantity measuring means 52. The amount of input heat is the amount of heat taken when the hot water flowing through the primary-side circulation passage 10 flows through the exchanger body 30, and is calculated by the following equation (1).

Input heat quantity E1 = (warm water temperature T1 on the inflow side of the exchanger body 30-warm water temperature T2 on the outflow side of the exchanger body 30) x warm water flow rate W1 of the primary side circulation passage 10
= (Detected temperature T1 of the first temperature sensor 54-Detected temperature T2 of the second temperature sensor 56) × Detected flow rate W1 of the first flow rate sensor 58 (1)
The output heat amount is the heat amount obtained when the hot water flowing through the secondary-side circulation passage 16 flows through the exchanger body 30, and is calculated by the following equation (2).

Output heat quantity E2 = (Warm water temperature T3 on the outflow side of the exchanger body 30−Warm water temperature T3 on the inflow side of the exchanger body 30) × Warm water flow rate W2 in the secondary circulation path 16
= (Detected temperature T4 of the fourth temperature sensor 64 -Detected temperature T3 of the third temperature sensor 62) × Detected flow rate W2 of the second flow sensor 66 (2)
The output ratio calculation means 73 calculates the ratio of the output heat quantity (E2) to the input heat quantity (E1), and is calculated by the following equation (3).

Output ratio P = (output heat E2 ÷ input heat E1) × 100
... (3)
This output ratio is 85 to 95% when there is no malfunction (for example, perforation) in the exchanger body 30 and heat exchange is normally performed, but the malfunction occurs in the exchanger body 30 and the primary side circulation flow When a part of the hot water in the passage 10 flows into the secondary side circulation passage 16, it changes to 96% or more. For this reason, the memory 78 stores a set ratio (for example, set to 97%) at which it is determined that a failure has occurred, and the abnormality determination means 74 uses the set ratio and the output ratio calculation means 73. The calculated output ratio is compared, and if the calculated output ratio exceeds the set ratio, it is determined that a problem has occurred in the exchanger body 30, and the abnormal signal generation means 76 generates an abnormal signal.

  The hot water heating system further includes alarm means 80. As the alarm means 80, a light alarm means composed of a light emitting diode or the like, a sound alarm means composed of a speaker or the like can be used, and the light alarm means is turned on to alert by light, and the sound alarm means is activated. Alarm with sound. Other configurations in the second embodiment are substantially the same as those in the first embodiment described above.

  Also in the second embodiment, when a malfunction occurs in the exchanger main body 30 during the heating operation (for example, a hole in the heat exchange tube 32), a hole in which a part of the hot water flowing through the primary side circulation passage 10 is opened. And flows into the secondary circulation passage 16. When the warm water flows in this way, the output ratio P (= E2 / E1) of the output heat quantity E2 of the warm water flowing through the secondary circulation path 16 to the input heat quantity E1 due to the warm water flowing through the primary circulation path 10 varies. However, as the amount of warm water flowing into the primary circulation path 10 increases, the output ratio increases. When the output ratio P exceeds the set ratio (for example, 97%) due to the inflow of hot water from the primary-side circulation flow path 10, the abnormality determination means 74 has failed in the exchanger body 30 (for example, the heat exchange tube 32). In this way, it is possible to detect the malfunction of the exchanger body 30, for example, the perforation.

  When the abnormality determining means 74 determines that there is an abnormality, the abnormality signal generating means 76 generates an abnormality signal, and based on this abnormality signal, the alarm means 80 is activated to issue an alarm, and this alarm causes a hole in the heat exchanger unit 6A. It is easy to know that an abnormality such as a gap has occurred. Further, based on this abnormal signal, the primary side circulation circuit 2A (the heat source unit 8 and the primary side feed pump 12) and the secondary side circulation circuit 4A (the secondary side feed pump 18 and the thermal valve 20) are stopped. You may make it do.

  As mentioned above, although embodiment of the heat exchanger unit according to this invention was described, this invention is not limited to these embodiment, A various deformation | transformation thru | or correction | amendment are possible without deviating from the scope of the present invention.

  This heat exchanger unit is a hot water that flows through the secondary side circulation circuit when a malfunction occurs in the exchanger body that performs heat exchange between the hot water in the primary side circulation circuit and the hot water in the secondary side circulation circuit, for example, when perforation occurs. Therefore, the occurrence of a malfunction can be detected by detecting this temperature fluctuation. The temperature variation of the hot water can be detected by the temperature detection means, and the occurrence of the malfunction can be easily detected based on the detected temperature of the temperature detection means. Instead of the temperature fluctuation of the hot water in the secondary side circulation circuit, the ratio of the output heat amount of the secondary side circulation circuit to the input heat quantity of the primary side circulation circuit, in other words, the fluctuation of the output ratio can be used. Generation | occurrence | production of a malfunction can be detected similarly based on the calorie | heat amount measured by an input calorie | heat amount measuring means and an output calorie | heat amount measuring means, and it can apply conveniently to the hot water heating system which heats indoor space using warm water.

It is a simplification figure showing simply an example of the hot water heating system containing the heat exchanger unit of a 1st embodiment. It is a figure which shows simply the other example of the hot water heating system containing the heat exchanger unit of 2nd Embodiment. It is a block diagram which shows simply the control system of the hot water heating system of FIG.

Explanation of symbols

2,2A Primary side circulation circuit 4,4A Secondary side circulation circuit 6,6A Heat exchanger unit 8 Heat source unit 10 Primary side circulation channel 14 Heat radiating device 16 Secondary side circulation channel 30 Exchanger body 32 Heat exchange tube 34 , 54, 56, 62, 64 Temperature sensor 52 Input calorie measuring means 58, 66 Flow rate sensor 60 Output calorie measuring means 68 Controller 70 Input calorie calculating means 72 Output calorie calculating means 73 Output ratio calculating means 74 Abnormality determining means 74

Claims (1)

A heat exchanger unit that performs heat exchange between the hot water flowing through the primary side circulation circuit including the heat source device and the hot water flowing through the secondary side circulation circuit including the heat dissipation device in the exchanger body,
The primary side circulation circuit is composed of an open circuit that is open to the atmosphere, the secondary side circulation circuit is composed of a sealed circuit that is sealed, and the primary side circulation circuit includes hot water that flows through the primary side circulation circuit. An input calorie measuring means for measuring the input calorie input is provided, and the secondary side circulation circuit has an output for measuring the output calorie output to the hot water flowing through the secondary side circulation circuit. The heat exchanger unit is provided with a heat quantity measuring means, and detects perforation of the exchanger body based on the heat quantity measured by the input heat quantity measuring means and the output heat quantity measuring means.

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