Chiller including a heat transfer tube and a method for controlling the chiller to determine the degree of contamination of the heat transfer tube

Abstract

To provide a chiller including a heat transfer tube and a method for controlling the chiller to determine the degree of contamination of the heat transfer tube.SOLUTION: A chiller includes: a cooling tower for storing cooling water to exchange heat with outside air; a condenser including a heat transfer tube through which the cooling water supplied from the cooling tower flows, and into which a refrigerant that exchanges heat with the cooling water flows; a cooling water outlet temperature sensor that is provided in a cooling water outlet pipe through which cooling water is discharged from the condenser, and detects a temperature of the discharged cooling water; a condenser pressure sensor that is provided in the condenser, and detects a pressure of the refrigerant inside the condenser; a controller that collects operation data by calculating a difference between a temperature detected by the cooling water outlet temperature sensor and a refrigerant temperature converted from the pressure detected by the condenser pressure sensor, and determines a degree of contamination caused by deposition of foreign matter in the cooling water flowing in the heat transfer tube of the condenser; and a display that outputs information on the degree of contamination when it is recognized that information regarding the difference deviates from a predetermined amount.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a chiller including a heat transfer tube and a control method for determining the degree of contamination of the heat transfer tube. [Background technology]

[0002] In general, a chiller supplies chilled water to a chilled water demand destination, and is characterized by performing heat exchange between a refrigerant circulating in a refrigeration system and chilled water circulating between the chilled water demand destination and the refrigeration system to cool the chilled water. Chillers are large-capacity facilities and are installed in large buildings, etc.

[0003] The chiller may include a cooling tower for cooling the cooling water. The cooling tower may be provided as an open cooling tower exposed to the outside environment, and the cooling water stored in the cooling tower is cooled through heat exchange with the outside air.

[0004] During the cooling process of the cooling water, foreign objects from the outside may enter the cooling tower, and the foreign objects may flow into the heat exchanger of the chiller and stick to the heat transfer tubes inside the heat exchanger.

[0005] Meanwhile, cooling water requires a large capacity of about several tens of tons as a fluid to circulate through the cooling tower and condenser, and the amount of cooling water that is used up during the evaporation process must be continuously supplied. Therefore, the cost of inputting cooling water is a heavy burden for manufacturers, and to solve this problem, they use industrial water, which is relatively cheap.

[0006] Therefore, depending on the degree of contamination of the industrial water itself, there is a high possibility that foreign matter will adhere to the heat transfer tubes of the heat exchanger.

[0007] In this way, foreign matter adhering to the heat transfer tubes reduces the heat exchange performance of the heat exchanger, lowering the reliability of the product.

[0008] To solve this problem, it is essential to clean the heat transfer tubes of the heat exchanger, but it is not easy to confirm whether the heat transfer tubes of the heat exchanger are contaminated to the extent that cleaning is required.

[0009] The most reliable method is to check the contamination state inside the heat transfer tubes using an endoscope or similar device, but such a check involves the burden of having to discharge large volumes of cooling water circulating through the cooling tower and heat exchanger to the outside.

[0010] Therefore, a method is required that can relatively accurately determine the degree of contamination of the heat exchanger without discarding the cooling water, and that can provide a user with a notification of the need to clean the heat transfer tubes when it is determined that the heat transfer tubes need cleaning. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention has been proposed to solve such problems, and has an object to provide a chiller that judges the degree of contamination of a heat transfer tube and provides a notification as to whether or not the heat transfer tube needs to be cleaned.

[0012] An object of the present invention is to provide a chiller that can determine the degree of contamination of a heat transfer tube by analyzing operation data of the chiller without providing a separate component for determining the degree of contamination of the heat transfer tube.

[0013] The present invention aims to provide a chiller equipped with operation logic that can recognize detected values ​​of existing sensors for cyclic operation of the chiller and calculate performance factors of a heat exchanger by processing the recognized data.

[0014] An object of the present invention is to provide a chiller that is equipped with operational logic that selectively extracts specific data that can be used to determine the degree of contamination of heat transfer tubes from a large amount of operational data recognized during chiller operation.

[0015] To select the particular data, the chiller cycle operation may be allowed time to stabilize and then the operational data may be extracted.

[0016] In order to select the specific data, operation data that is recognized when the value of a condenser level sensor provided in the condenser falls within a specific range can be extracted.

[0017] In order to select the specific data, it is possible to extract operating data that is recognized when the difference between the condenser refrigerant temperature and the cooling water outlet temperature falls within a set range.

[0018] In order to select the specific data, operation data recognized when a hot gas valve provided in a chiller is in an off state can be extracted.

[0019] In order to select the specific data, operation data that is recognized when the difference between the coolant outlet temperature and the coolant inlet temperature falls within a set range can be extracted.

[0020] The present invention aims to provide a chiller that can accumulate and store operation data according to the chiller's operation cycle and process the stored operation data to determine an increasing trend in contamination level, taking into consideration foreign matter in heat transfer tubes that gradually accumulates over a long period of time.

[0021] With respect to the operating cycle, a new operating cycle begins when the chiller is turned on after being turned off, or when a specific time in a day has passed if the chiller has been turned on continuously for more than one day. [Means for solving the problem]

[0022] An embodiment of the present invention may include a condenser having a heat transfer tube through which cooling water flows, and may include a sensor for detecting the refrigerant temperature of the condenser and the temperature of the cooling water in order to recognize the degree of contamination of the heat transfer tube.

[0023] The sensor may include a condenser pressure sensor for sensing a pressure of the refrigerant passing through a condenser. A saturation temperature may be calculated from the pressure sensed by the condenser pressure sensor, and the calculated saturation temperature may be recognized as the refrigerant temperature of the condenser.

[0024] The sensor may include a cooling water outlet temperature sensor for sensing an outlet temperature of the cooling water discharged from the condenser.

[0025] The present invention may further include a controller capable of recognizing a degree of contamination of the heat transfer tube based on a difference between the refrigerant temperature and the cooling water temperature of the condenser. The temperature difference may constitute a factor indicating the heat exchange performance of the condenser.

[0026] The controller can selectively collect operational data according to the operating state of the chiller during the period in which the chiller is operated.

[0027] The controller may collect data sensed by the sensor after the chiller is turned on and a period of time for the cycle to stabilize has elapsed, and may determine the degree of contamination of the heat transfer tube based on the collected data.

[0028] As an example, the time required for the cycle to stabilize may be a time value determined within a range of 5 to 10 minutes.

[0029] The controller can recognize a value of a condenser level sensor provided in a condenser, and selectively collect operation data based on the recognized refrigerant level of the condenser.

[0030] As an example, operational data may be collected when the refrigerant level in the condenser is below a set level, and collection of operational data may cease when the refrigerant level is above the set level.

[0031] The controller can recognize a difference between the condenser refrigerant temperature and the cooling water outlet temperature, and selectively collect operating data based on the difference.

[0032] As an example, when the difference value is equal to or greater than a set value, the operation data can be collected, and when the difference value is equal to or less than the set value, the collection of the operation data can be stopped.

[0033] The controller can recognize whether a hot gas valve provided in a chiller is on-open or off-closed, and selectively collect operation data based on the recognition result.

[0034] For example, when the hot gas valve is turned off, the operation data can be collected, and when the hot gas valve is turned on, the collection of the operation data can be stopped.

[0035] The controller can recognize a difference between the cooling water outlet temperature and the cooling water inlet temperature, and selectively collect operating data based on the difference.

[0036] As an example, the operating data may be collected when the difference is within a set value, and the collecting of the operating data may be stopped when the difference is equal to or greater than the set value.

[0037] The controller may collect and update operation data for each operation cycle of the chiller and process the collected operation data to determine an increasing trend of the contamination level. The operation data may be data regarding a difference between a refrigerant temperature of a condenser and an outlet temperature of the cooling water.

[0038] For example, the operation cycle may be divided based on a point in time when the chiller is turned on after being turned off, or may be divided based on a specific point in time during a day when the operation continues for more than one day.

[0039] The controller may calculate an average value of the collected driving data for multiple driving cycles. By way of example, the average value may be an average value for each driving cycle or an aggregate average value for two or more driving cycles.

[0040] To implement a simple control logic, for example, the controller may calculate an average value for a number of operating cycles corresponding to one month.

[0041] The controller may calculate a change in the calculated average values. For example, the controller may calculate the change based on a first average value of the driving data corresponding to a first month, a second average value of the driving data corresponding to a second month, and a third average value of the driving data corresponding to a month thereafter.

[0042] As an example, such mean change calculations may be performed over a period of 6 to 12 months.

[0043] The controller can recognize the degree of contamination of the heat transfer tube of the condenser based on the average value or the amount of change in the average value.

[0044] As an example, if the number of times that the average value is recognized to be equal to or greater than a preset value is equal to or greater than a set number of times, or if the amount of change in the average value is recognized to be equal to or greater than a preset value, the controller can recognize that the level of contamination of the heat transfer tube of the condenser has become serious.

[0045] In this case, the controller can output a notification regarding the cleaning of the heat transfer tube through a display unit.

[0046] In one aspect, a chiller according to an embodiment of the present invention may include a cooling tower that stores cooling water that exchanges heat with outside air, a heat transfer tube through which the cooling water supplied from the cooling tower flows, a condenser into which a refrigerant that exchanges heat with the cooling water in the heat transfer tube flows, a cooling water outlet temperature sensor that is provided in a cooling water outflow piping that discharges the cooling water from the condenser and detects a temperature of the discharged cooling water, and a condenser pressure sensor that is provided inside the condenser and detects a refrigerant pressure inside the condenser.

[0047] The chiller may further include a controller that calculates a difference between a value detected by the cooling water outlet temperature sensor and a refrigerant temperature value converted by the condenser pressure sensor to collect operation data so as to recognize a contamination level of the cooling water due to deposition of foreign matter on a heat transfer tube of the condenser.

[0048] The chiller may further include a display unit that outputs information about the contamination level when it is determined that information about the difference value deviates from a set value.

[0049] The controller may further include a memory unit that updates and stores information about the difference value for each operation cycle, and the controller may calculate an average value of the difference values ​​for each operation cycle stored in the memory unit.

[0050] When the controller recognizes that the number of times that the average value is recognized to be equal to or greater than a predetermined first set value is equal to or greater than a set number of times, the controller can output information regarding the degree of contamination of the heat transfer tube to the display unit.

[0051] When the controller determines that the amount of change in the average value for each of the plurality of operation cycles is equal to or greater than a second set value, the controller may output information regarding the contamination level of the heat transfer tube to the display unit.

[0052] The controller may stop the process of calculating the difference value and collecting the operating data when a preset event occurs during the process of recognizing the pollution level.

[0053] The system may further include a condenser level sensor that detects the level of the refrigerant stored in the condenser, and the controller may stop collecting the operating data when it determines that the value detected by the condenser level sensor is equal to or greater than a set value.

[0054] The controller may stop collecting the operating data when it determines that the difference between the value sensed by the cooling water outlet temperature sensor and the refrigerant temperature value converted by the condenser pressure sensor is equal to or less than a set value.

[0055] The compressor may further include an expansion device for reducing the pressure of the refrigerant condensed in the condenser, an evaporator for evaporating the refrigerant reduced in pressure in the expansion device, and a hot gas valve installed in a connecting pipe connecting the condenser and the evaporator and opened to bypass the refrigerant in the condenser to the evaporator.

[0056] The controller may cease collecting the operational data when the hot gas valve is recognized to be open.

[0057] The condenser may further include a cooling water inlet temperature sensor provided in a cooling water inlet pipe for inflowing cooling water into the condenser and detecting a temperature of the inflowing cooling water, and the controller may stop collecting the operating data when it recognizes that a difference between the inlet water temperature and the outlet water temperature of the condenser is equal to or greater than a set value.

[0058] The cooling system may further include water boxes provided on both sides of the heat transfer tube of the condenser to provide a space for cooling water to flow, and the cooling water outlet pipe is connected to the water boxes.

[0059] The heat transfer tube of the condenser includes first and second heat transfer tubes separated by a separation plate, and flow holes are formed between the separation plate and both ends of the condenser to guide the refrigerant that has undergone heat exchange in the first heat transfer tube to the second heat transfer tube.

[0060] From another perspective, a method for controlling a chiller according to an embodiment of the present invention relates to a method for controlling a chiller including a cooling tower that stores cooling water that exchanges heat with outside air, a condenser including a heat transfer tube through which the cooling water supplied from the cooling tower flows and into which a refrigerant that exchanges heat with the cooling water in the heat transfer tube flows, a cooling water outlet temperature sensor provided in a cooling water outflow piping that discharges the cooling water from the condenser and detects a temperature of the discharged cooling water, and a condenser pressure sensor provided inside the condenser and detects a refrigerant pressure inside the condenser.

[0061] The control method may include a step of collecting operation data by a controller calculating a difference between a value sensed by the cooling water outlet temperature sensor and a refrigerant temperature value converted by the condenser pressure sensor.

[0062] The control method may further include a step of the controller outputting information about the contamination level to a display unit when the controller recognizes that information about the difference value deviates from a set value.

[0063] The chiller may further include a memory unit that updates and stores information regarding the difference value for each operation cycle, and the controller may calculate an average value of the difference values ​​for each operation cycle stored in the memory unit.

[0064] When the number of times that the average value is recognized to be equal to or greater than a first set value is equal to or greater than a set number of times, or when it is recognized that the amount of change in the average value for each of the plurality of operating cycles is equal to or greater than a second set value, information regarding the degree of contamination of the heat transfer tube can be output to the display unit.

[0065] The controller may stop the process of calculating the difference value and collecting the operating data when a preset event occurs during the process of recognizing the pollution level.

[0066] The preset event may include at least one of a first event recognizing that a value sensed by a condenser level sensor is equal to or greater than a set value, a second event recognizing that a difference between a value sensed by the cooling water outlet temperature sensor and a refrigerant temperature value converted by the condenser pressure sensor is equal to or less than a set value, a third event recognizing that a hot gas valve that opens to bypass the refrigerant inside the condenser to the evaporator has been opened, and a fourth event recognizing that a difference between an inlet water temperature and an outlet water temperature of the condenser is equal to or greater than a set value. Effect of the Invention

[0067] According to the present invention, the degree of contamination of a heat transfer tube can be determined and notification as to whether or not the heat transfer tube needs to be cleaned can be provided, thereby enabling efficient management of the chiller and maintaining good operating performance of the chiller.

[0068] According to the present invention, since the contamination level of the heat transfer tube can be determined by analyzing the operation data of the chiller without providing a separate component for determining the contamination level of the heat transfer tube, the cost efficiency is improved.

[0069] According to the present invention, an operation logic is provided that can recognize the sensed values ​​of existing sensors for cyclic operation of a chiller and calculate the performance factors of a heat exchanger by processing the recognized data, so that a simple operation logic can be implemented.

[0070] According to the present invention, an operational logic is provided that selectively extracts specific data that can be used to determine the level of contamination of a heat transfer tube from the large amount of operational data recognized during chiller operation, thereby improving the accuracy of determining the level of contamination of the heat transfer tube.

[0071] In other words, rather than always collecting operating data to determine the degree of contamination of the heat transfer tube after the chiller is operated, if an event occurs in which the operating data cannot reflect the degree of contamination of the heat transfer tube depending on the cycle operation mode, operating data is not collected, thereby preventing errors in the collected operating data.

[0072] According to the present invention, when considering foreign matter in a heat transfer tube that gradually accumulates over a long period of time, operation data is accumulated and stored according to the operation cycle of the chiller, and the stored operation data is processed to determine an increasing trend in the level of contamination, thereby realizing sustainable and efficient management of the chiller. [Brief description of the drawings]

[0073] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a chiller according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cycle diagram showing the configuration of a chiller according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing a partial configuration of a chiller according to an embodiment of the present invention. [Figure 4] FIG. 4 is a cross-sectional view showing the internal configuration of a condenser of a chiller according to an embodiment of the present invention. [Diagram 5] FIG. 5 is a cross-sectional view taken along line 5-5' of FIG. [Figure 6] FIG. 6 is a block diagram showing a configuration for controlling a chiller according to an embodiment of the present invention. [Figure 7] FIG. 7 is a flowchart showing a chiller control method according to an embodiment of the present invention. [Figure 8] FIG. 8 is a flowchart showing a chiller control method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0074] Hereinafter, some embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals. In addition, in the description of the embodiments of the present invention, if a detailed description of a known configuration or function is determined to hinder understanding of the embodiments of the present invention, the detailed description will be omitted.

[0075] In addition, in describing components of the embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. Such terms are used to distinguish the components from other components, and do not limit the essence or order of the components. When a component is described as being "coupled," "coupled," or "connected" to another component, this includes both cases where the component is directly coupled or connected to the other component, and cases where other components are further "coupled," "coupled," or "connected" between each component.

[0076] FIG. 1 is a schematic diagram showing the configuration of a chiller according to an embodiment of the present invention, and FIG. 2 is a cycle diagram showing the configuration of a chiller according to an embodiment of the present invention.

[0077] 1 and 2, a chiller 10 according to an embodiment of the present invention may include a cooling module 100 in which a refrigeration cycle is formed, and a cooling tower 20 that supplies cooling water to the cooling module 100.

[0078] The cooling tower 20 is exposed to the outside air, and the cooling water stored in the cooling tower 20 is cooled by exchanging heat with the outside air. The cooling water can evaporate by exchanging heat with the outside air, and is cooled in the evaporation process.

[0079] The cooling tower 20 is equipped with a flow switch that detects the level of the stored cooling water, and when the level of the cooling water drops due to evaporation, a pump is operated to replenish the cooling tower 20 with cooling water.

[0080] The cold water exchanged with the cooling module 100 is supplied to a demand destination 30. The demand destination 30 can be understood as a device or space that performs air conditioning using the cold water.

[0081] A cooling water circulation flow path 40 is provided between the cooling module 100 and the cooling tower 20. The cooling water circulation flow path 40 can be understood as a pipe that guides the cooling water to circulate between the cooling tower 20 and the condenser 120 of the cooling module 100.

[0082] The cooling water circulation flow path 40 includes a cooling water inlet flow path 42 that guides the cooling water to flow into the condenser 120 and a cooling water outlet flow path 44 that guides the cooling water heated in the condenser 120 to flow into the cooling tower 20.

[0083] A cooling water pump 46 that is driven to flow the cooling water is provided in at least one of the cooling water inlet flow path 42 and the cooling water outlet flow path 44. As an example, FIG. 1 illustrates that the cooling water pump 46 is provided in the cooling water inlet flow path 42.

[0084] The cooling water outlet flow passage 44 is provided with an outlet water temperature sensor 47 for detecting the temperature of the cooling water flowing into the cooling tower 20. And, the cooling water inlet flow passage 42 is provided with an inlet water temperature sensor 48 for detecting the temperature of the cooling water discharged from the cooling tower 20.

[0085] A cold water circulation flow path 50 is provided between the cooling module 100 and the demand destination 30. The cold water circulation flow path 50 can be understood as a pipe that guides cold water to circulate between the demand destination 30 and the evaporator 140 of the cooling module 100.

[0086] The cold water circulation flow path 50 includes a cold water inlet flow path 52 that guides cold water to flow into the evaporator 120 and a cold water outlet flow path 54 that guides the cooled cold water from the evaporator 140 to flow to the demand destination 30.

[0087] A cold water pump 56 that is driven to flow cold water is provided in at least one of the cold water inlet flow path 52 and the cold water outlet flow path 54. As an example, FIG. 1 illustrates that the cold water pump 56 is provided in the cold water inlet flow path 52.

[0088] The demand destination 30 may be a water-cooled air conditioner that exchanges heat between air and cold water.

[0089] As an example, the demand destination 30 includes at least one of an air handling unit (AHU) that mixes indoor air with outdoor air, exchanges heat between the mixed air and cold water, and discharges the mixed air into the room, a fan coil unit (FCU) that is installed indoors and exchanges heat between the indoor air and cold water, and discharges the mixed air into the room, and a floor piping unit that is buried in the floor of the room.

[0090] FIG. 1 shows, as an example, the demand destination 30 being composed of an air handling unit.

[0091] In detail, the air handling unit includes a casing 61, a cold water coil 62 installed inside the casing 61 and through which cold water passes, and fans 63 and 64 provided on both sides of the cold water coil 62 to draw in indoor air and outdoor air and blow it into the room.

[0092] The fans 63 and 64 include a first fan 63 for drawing indoor air and outdoor air into the casing 61 and a second fan 64 for discharging conditioned air to the outside of the casing 61.

[0093] The casing 61 is formed with an indoor air intake section 65, an indoor air discharge section 66, an outdoor air intake section 67, and an air-conditioned air discharge section 68.

[0094] When the fans 63, 64 are driven, a portion of the air sucked into the indoor air intake section 65 from the room is discharged to the indoor air discharge section 66, and the remainder that is not discharged to the indoor air discharge section 66 is mixed with the outdoor air sucked into the outdoor air intake section 67 and exchanges heat with the chilled water coil 62.

[0095] The mixed air that has been heat exchanged (cooled) with the cold water coil 62 is discharged into the room through the conditioned air discharge portion 68.

[0096] The cooling module 100 includes a compressor 110 for compressing a refrigerant, a condenser 120 into which the high-temperature, high-pressure refrigerant compressed by the compressor 110 flows, an expansion device 130 for reducing the pressure of the refrigerant condensed by the condenser 120, and an evaporator 140 for evaporating the refrigerant reduced in pressure by the expansion device 130.

[0097] The expansion device 130 may include, for example, an electronic expansion valve (EEV) whose opening degree is adjustable.

[0098] The cooling module 100 includes an intake pipe 101 provided on the inlet side of the compressor 110 for guiding the refrigerant discharged from the evaporator 140 to the compressor 110, and a discharge pipe 102 provided on the outlet side of the compressor 110 for guiding the refrigerant discharged from the compressor 110 to the condenser 120.

[0099] An oil recovery pipe 108 is provided between the evaporator 140 and the compressor 110 to guide the oil present inside the evaporator 140 to the suction side of the compressor 110 .

[0100] The condenser 120 and the evaporator 140 are configured as shell-and-tube heat exchange devices to enable heat exchange between the refrigerant and water.

[0101] In detail, the condenser 120 includes a shell 121 that forms an exterior, a refrigerant inlet 122 formed on one side of the shell 121 into which the refrigerant compressed in the compressor 110 flows, and a refrigerant outlet 123 formed on the other side of the shell 121 into which the refrigerant condensed in the condenser 120 flows. The shell 121 is formed in a substantially cylindrical shape.

[0102] The condenser 120 includes an internal pipe 125 provided inside the shell 121 to guide the flow of cooling water, a cooling water inlet pipe 151 formed at an end of the shell 121 to allow the cooling water to flow into the internal pipe 125, and a cooling water outlet pipe 152 formed at an end of the shell 121 to allow the cooling water to be discharged from the cooling water pipe 125.

[0103] Cooling water flows through the internal pipe 125 and exchanges heat with the refrigerant inside the shell 121 that has flowed in through the refrigerant inlet portion 122. The internal pipe 125 can be called a "cooling water heat transfer pipe."

[0104] The cooling water inflow pipe 151 is connected to the cooling water inlet passage 42 , and the cooling water outflow pipe 152 is connected to the cooling water outlet passage 44 .

[0105] The evaporator 140 includes a shell 141 that forms an exterior, a refrigerant inlet 142 formed on one side of the shell 141 and into which the refrigerant expanded in the expansion device 130 flows, and a refrigerant outlet 143 formed on the other side of the shell 141 and into which the refrigerant evaporated in the evaporator 140 flows out. The refrigerant outlet 143 is connected to the suction pipe 101.

[0106] The evaporator 140 includes an internal pipe 145 provided inside the shell 141 to guide the flow of cold water, a cold water inlet pipe 161 formed at an end of the shell 141 to allow cold water to flow into the internal pipe 145, and a cold water outlet pipe 162 formed at an end of the shell 141 to allow cold water to flow out of the internal pipe 145.

[0107] Cold water flows inside the internal pipe 145 and exchanges heat with the refrigerant inside the shell 141 that has flowed in through the refrigerant inlet 142. The internal pipe 145 can be called a "cold water heat transfer pipe."

[0108] The cold water inlet pipe 161 is connected to the cold water inlet passage 52 , and the cold water outlet pipe 162 is connected to the cold water outlet passage 54 .

[0109] The internal pipe 125 of the condenser 120 and the internal pipe 145 of the evaporator 140 may be collectively referred to as the "water pipe."

[0110] FIG. 3 is a diagram showing a partial configuration of a chiller according to an embodiment of the present invention, FIG. 4 is a cross-sectional view showing the internal configuration of a condenser of a chiller according to an embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along line 5-5' in FIG. 4.

[0111] 3 to 5, a cooling module 100 according to an embodiment of the present invention may include a compressor 110, a condenser 120, and an evaporator 140.

[0112] For example, the condenser 120 and the evaporator 140 are arranged side by side in the left-right direction, and the compressor 110 is arranged above the evaporator 140 .

[0113] The cooling module 100 may include a discharge pipe 102 extending downward from the compressor 110 and connected to the condenser 120, and a suction pipe 101 extending upward from the evaporator 140 and connected to the evaporator 140.

[0114] The cooling module 100 may further include an inverter 175 for controlling the power of the compressor 110. The inverter 175 is disposed above the condenser 120, for example.

[0115] The cooling module 100 may further include a hot gas valve 171 installed in a hot gas pipe connecting the condenser 120 and the evaporator 140. The hot gas pipe may be understood as a pipe connecting an upper end of the condenser 120 and an upper end of the evaporator 140.

[0116] The cooling module 100 may further include a capacity control valve 180 for controlling the capacity of the compressor 110. The capacity control valve 180 is provided in the suction pipe 101 of the compressor 110.

[0117] A sensor for detecting a state of the refrigerant is installed in the condenser 120. The sensor may include a condenser level sensor 220 for detecting a level of the refrigerant present in the condenser 120.

[0118] The condenser level sensor 220 is installed at a position that is a set height higher than the lower end of the shell 121 of the condenser 120. As an example, the condenser level sensor 220 may be installed at a position that turns on when the refrigerant fills 70% of the internal capacity of the shell 121.

[0119] The sensors may further include a condenser pressure sensor 210 for detecting the pressure of the refrigerant inside the condenser 120. The pressure value detected by the condenser pressure sensor 210 is converted into a saturation temperature and recognized as the refrigerant temperature of the condenser. As an example, the condenser pressure sensor 210 may be installed on an outer circumferential surface of a shell 121 of the condenser 120.

[0120] The cooling module 100 may further include a controller 200 for controlling the operation of the chiller 10. As an example, the controller 200 may be disposed adjacent to one side of the compressor 110.

[0121] The cooling module 100 may further include a hot gas valve 171 that is opened to supply the refrigerant of the condenser 120 to the evaporator 140. The hot gas valve 171 is installed in a connection pipe 170 that connects an upper end of the condenser 120 and an upper end of the evaporator 140.

[0122] When the cooling load required by the chiller 10 is not large, the hot gas valve 171 is opened, and the refrigerant in the high-pressure condenser 120 can flow to the low-pressure evaporator 140 through the opened hot gas valve 171. Therefore, the condensation capacity of the condenser 120 is low, and the temperature of the refrigerant passing through the condenser 120 or the outlet temperature of the cooling water can be maintained at a relatively low temperature.

[0123] A cooling water inlet temperature sensor 231 for detecting the temperature of the inflowing cooling water is installed in a cooling water inlet pipe 151 for guiding the inflow of the cooling water to the condenser 120. A cooling water outlet temperature sensor 235 for detecting the temperature of the discharged cooling water is installed in a cooling water outlet pipe 152 for guiding the discharge of the cooling water from the condenser 120.

[0124] The cooling water inlet temperature sensor 231 and the cooling water outlet temperature sensor 235 are installed on the outer circumferential surfaces of the respective pipes 151 and 152 and protrude into the respective pipes 151 and 152 to sense the temperature of the cooling water.

[0125] A cold water inlet temperature sensor 241 for detecting the temperature of the cold water is installed in a cold water inlet pipe 161 for guiding the cold water to the evaporator 140. A cold water outlet temperature sensor 245 for detecting the temperature of the cold water is installed in a cold water outlet pipe 162 for guiding the cold water to be discharged from the evaporator 140.

[0126] The cold water inlet temperature sensor 241 and the cold water outlet temperature sensor 245 are installed on the outer circumferential surfaces of the respective pipes 161 and 162 and protrude into the respective pipes 161 and 162 to sense the temperature of the cold water.

[0127] The cooling module 100 may include water boxes 150 and 160 provided on both sides of the condenser 120 and the evaporator 140. The water boxes 150 and 160 provide a flow space for cooling water or cold water.

[0128] The water boxes 150 and 160 may include a condenser water box 150 provided on both sides of the condenser 120 to provide a space for cooling water to flow. The water boxes 150 and 160 may include an evaporator water box 160 provided on both sides of the evaporator 140 to provide a space for cooling water to flow.

[0129] The condenser water box 150 is provided between the condenser 120 and the cooling water inlet pipes 151 and 152 of the condenser 120. The cooling water flowing in through the cooling water inlet pipe 151 can flow into the inside of the condenser 120 via the condenser water box 150.

[0130] The cooling water that has exchanged heat with the refrigerant in the condenser 120 is discharged to the condenser water box 150 and then discharged to the outside through the cooling water outlet pipe 152.

[0131] The evaporator water box 160 is provided between the evaporator 140 and cold water inlet pipes 161 and 162 of the evaporator 140. Cold water flowing in through the cold water inlet pipe 161 can flow into the inside of the evaporator 140 via the evaporator water box 160.

[0132] The cold water that has exchanged heat with the refrigerant in the evaporator 140 is discharged to the evaporator water box 160 and then discharged to the outside through the cold water outlet pipe 162.

[0133] The internal and peripheral configuration of the condenser 120 will be described in more detail with reference to FIG.

[0134] The condenser 120 may include a cylindrical shell 121 lying approximately horizontally and defining an internal space, a number of internal pipes 125 provided inside the shell 121 to guide the flow of cooling water, and a condenser water box 150 provided on both sides of the shell 121 to form a flow space for the cooling water.

[0135] The plurality of internal pipes 125 extend laterally from one side of the shell 121 to the other side and are coupled to a shell coupling plate 129. The shell coupling plate 129 is provided on both sides of the shell 121.

[0136] The shell 121 has an upper end provided with a refrigerant inlet 122 for guiding the inflow of the refrigerant, and a lower end provided with a refrigerant outlet 123 for guiding the discharge of the refrigerant.

[0137] The internal pipes 125 are arranged in a vertical direction. The refrigerant flowing in through the refrigerant inlet 122 exchanges heat with the upper pipes of the internal pipes 125, is condensed, and flows downward to continuously exchange heat with the lower pipes.

[0138] The refrigerant condensed by heat exchange with the lower piping is discharged to the outside of the shell 121 through the refrigerant outlet 123 .

[0139] The plurality of internal pipes 125 may include a first heat transfer pipe 125a forming the upper pipe and a second heat transfer pipe 125b forming the lower pipe.

[0140] The first heat transfer tube 125a can be understood as a condensation heat transfer tube for condensing the gas phase refrigerant that flows into the condenser 120, and the second heat transfer tube 125b can be understood as a subcooling heat transfer tube for additionally cooling the refrigerant condensed in the first heat transfer tube 125a.

[0141] A separation plate 127 is provided between the first heat transfer tube 125a and the second heat transfer tube 125b. The separation plate 127 can be understood as a collection plate for collecting the refrigerant that has exchanged heat with the first heat transfer tube 125a.

[0142] Flow holes 127a for guiding the refrigerant to flow toward the second heat transfer tube 125b are formed between the separation plate 127 and the shell connecting plate 129. The flow holes 127a are formed on both sides of the separation plate 127.

[0143] The refrigerant flowing downward through the flow holes 127a flows toward the center of the second heat transfer tube 125b and is discharged to the outside of the shell 121 through the refrigerant outlet 123. The refrigerant outlet 123 may be located approximately in the center in the lateral direction of the shell 121. With this configuration, the heat exchange area between the refrigerant and the first and second heat transfer tubes 125a and 125b is increased, improving the heat exchange efficiency.

[0144] A guide plate 126 for guiding the refrigerant flowing in through the refrigerant inlet 122 to both sides of the first heat transfer tube 125a is provided inside the shell 121. The guide plate 126 is disposed adjacent to the refrigerant inlet 122.

[0145] The guide plate 126 prevents the refrigerant flowing in through the refrigerant inlet portion 122 from directly colliding with the first heat transfer tube 125a, thereby reducing the flow velocity of the refrigerant and facilitating heat exchange with the first heat transfer tube 125a.

[0146] A condenser water box 150 is coupled to the outer side of the shell coupling plate 129. The condenser water box 150 may include a first water box 150a to which a cooling water inlet pipe 151 and a cooling water outlet pipe 152 are coupled.

[0147] A partition plate 155 is provided inside the first water box 150a to separate the internal space of the first water box 150a. A first space partitioned by the partition plate 155 may form an inflow space through which the cooling water flowing in through the cooling water inflow pipe 151 flows, and a second space partitioned by the partition plate 155 may form an outflow space through which the cooling water discharged through the cooling water outflow pipe 152 flows.

[0148] The partitioned first space may be in communication with a portion of the first heat transfer tube 125a and the second heat transfer tube 125b. The cooling water in the first space may flow into the portion of the first heat transfer tube 125a and the second heat transfer tube 125b to exchange heat.

[0149] The partitioned first space, a portion of the first heat transfer pipe 125a, and the second heat transfer pipe 125b may form a cooling water inflow region Z1 (see FIG. 5).

[0150] The partitioned second space and the remaining piping of the first heat transfer pipe 125a may form an outflow area Z2 (see FIG. 5) for the cooling water.

[0151] The condenser water box 150 may include a second water box 150b provided on the opposite side of the first water box 150a. The cooling water flowing into the condenser 120 through the cooling water inlet region Z1 may flow into the second water box 150b.

[0152] The cooling water in the second water box 150b may exchange heat by flowing through the remaining piping of the first heat transfer pipe 125a. The heat-exchanged cooling water flows into the second partitioned space and is discharged to the outside of the condenser 120 through the cooling water outlet piping 152.

[0153] Due to the flow of the cooling water in the condenser 120, foreign matter F contained in the cooling water may be deposited in the internal pipe 125. If the amount of the deposited foreign matter increases during the course of using the cooling module 100 for a long time, the cross-sectional area of ​​the flow of the internal pipe 125 is reduced, and the heat exchange performance between the refrigerant and the cooling water is reduced due to the foreign matter.

[0154] In order to solve this problem, it is necessary to determine the degree of contamination of the internal pipe 125 by analyzing the operation data of the cooling module 100 without directly checking the inside of the internal pipe 125 .

[0155] FIG. 6 is a block diagram showing a configuration for controlling a chiller according to an embodiment of the present invention, and FIGS. 7 and 8 are flowcharts showing a method for controlling a chiller according to an embodiment of the present invention.

[0156] First, referring to FIG. 6, a chiller 10 according to an embodiment of the present invention may include a number of sensors capable of ascertaining information regarding the operation of the chiller.

[0157] The multiple sensors may include a cooling water inlet temperature sensor 231 for sensing the temperature of the cooling water flowing into the condenser 120 and a cooling water outlet temperature sensor 235 for sensing the temperature of the cooling water discharged from the condenser 120.

[0158] The multiple sensors may further include a condenser pressure sensor 210 for sensing the refrigerant pressure inside the condenser 120 .

[0159] The multiple sensors may include a condenser level sensor 220 for sensing the level of the refrigerant stored in the condenser 120 .

[0160] The chiller 10 may further include a timer 260 for detecting an operation time of the chiller 10. The timer 260 may accumulate a time that has elapsed since the chiller 10 is turned on, a time that has elapsed since the plurality of sensors detect specific values, or a time that has elapsed since the compressor 110, the expansion device 130, and the pumps 46 and 56 are driven.

[0161] The chiller 10 may further include a memory unit 270 that stores information regarding the operation of the chiller 10. As an example, the chiller 10 may operate according to a preset cycle, and operation data sensed at each cycle is updated in the memory unit 270.

[0162] The chiller 10 may further include a controller 200 that controls operation of the compressor 110, the expansion device 130, and the pumps 46 and 56 based on information sensed by the multiple sensors 231, 235, 210, and 220, time information accumulated by the timer 260, or information stored in the memory unit 270.

[0163] The chiller 10 may further include a display unit 250 that displays information regarding the degree of contamination to a user or notifies the user that the internal pipe 125 needs to be cleaned when it is determined that the degree of contamination due to foreign matter or the like in the internal pipe 125 of the condenser 120 has reached or exceeded a set contamination level.

[0164] Hereinafter, a method of controlling the chiller 10 for determining the degree of contamination of the internal piping 125 of the condenser 120 will be described with reference to FIGS.

[0165] When the chiller 10 is powered on and starts operating (S11), the controller 200 can load information from a previous operation cycle (S12).

[0166] For example, the operation cycle of the chiller 10 may be reset based on a specific time (12:00 a.m.) based on a day, and may be reset when the chiller 10 is turned on again after being turned off.

[0167] The operation information may include information on an index for determining the heat exchange capacity of the heat exchangers 120 and 140 (hereinafter, heat exchange index information).

[0168] The heat exchange index information is a criterion for judging the heat exchange capacity between the refrigerant and the water, and is determined based on the temperature difference between the water and the refrigerant.

[0169] The heat exchange index information of the evaporator 140 among the heat exchangers 120 and 140 is determined based on the difference between the chilled water outlet temperature and the evaporator refrigerant temperature. Due to the characteristics of the chilled water circulating along a closed circuit, the internal piping of the evaporator 140 is less likely to be contaminated by foreign matter.

[0170] The heat exchange index information of the condenser 120 of the heat exchangers 120 and 140 is determined based on the difference between the refrigerant temperature of the condenser and the coolant outlet temperature. As an example, the heat exchange index information of the condenser 120 is determined by the value of (condenser refrigerant temperature-coolant outlet temperature).

[0171] Due to the characteristics of the cooling water circulating through the cooling tower 20 exposed to the outside air, the internal piping of the condenser 120 is highly likely to be contaminated by foreign matter.

[0172] The refrigerant temperature of the condenser is calculated by converting the pressure value sensed by the condenser pressure sensor 210 into a saturation temperature. The coolant outlet temperature can be understood as a temperature value sensed by the coolant outlet temperature sensor 235.

[0173] The refrigerant temperature of the condenser cannot be artificially adjusted because it varies depending on the state of the cycle being operated. Therefore, the heat exchange index information of the condenser 120 is determined according to the change in the coolant outlet temperature.

[0174] It can be understood that the larger the heat exchange index value of the condenser 120, the relatively lower the heat exchange capacity between the refrigerant and the coolant, and the smaller the heat exchange index value, the relatively higher the heat exchange capacity between the refrigerant and the coolant. Based on the phenomenon that the coolant cools the refrigerant, it can be understood that the smaller the difference between the refrigerant temperature and the coolant temperature, the higher the heat exchange capacity.

[0175] After the chiller 10 is operated, it may be waited for a stabilization time of the cycle to elapse. After the chiller 10 is turned on and starts to operate, it is necessary to wait a set time to form a pressure / temperature distribution of a required cycle. As an example, the set time may be determined within a range of 5 to 10 minutes after the chiller 10 is turned on and driven.

[0176] This is because it is difficult for the heat exchange index value of the condenser sensed before the set time has elapsed to reflect the accurate state of the cycle being operated.

[0177] Of course, if the chiller 10 is continuously driven from the previous cycle to the current cycle (always driven), the process of waiting until the stabilization time has elapsed is not necessary (S13).

[0178] After the stabilization time of the cycle has elapsed, operation data can be collected to determine the degree of contamination of the internal piping of the condenser 120, i.e., the first and second heat transfer tubes 125a and 125b. However, the operation data may show abnormal values ​​due to various causes based on the cycle state or operation mode, etc. Therefore, it is necessary to remove such abnormal values ​​as error messages.

[0179] For this reason, it can be recognized whether an event that limits the collection of driving data has occurred (S15). Examples of events that stop the collection of driving data are as follows.

[0180] The first event is whether the value sensed by the condenser level sensor 220 is equal to or greater than a preset value. As an example, the preset value can be understood to be the value sensed by the sensor 220 when the refrigerant fills 70% of the internal volume of the shell 121.

[0181] Collection of operation data is stopped when the value detected by the condenser level sensor 220 is equal to or higher than the set value. When the value detected by the condenser level sensor 220 is equal to or higher than the set value, it corresponds to a case where the level of the refrigerant stored in the condenser 120 is excessively high, and in this case, the condensation of the refrigerant in the condenser 120 is relatively not performed smoothly.

[0182] In this state, the heat exchange index value of the condenser 120 becomes excessively high, and if this is used as information for judging the contamination level of the heat transfer tube of the condenser, the judgment regarding the contamination level of the heat transfer tube of the condenser 120 will be inaccurate. That is, even if the contamination level of the heat transfer tube is low, an error will occur in which the contamination level is judged to be high.

[0183] The second event is whether or not the heat exchange index value of the condenser is equal to or less than a set value. As an example, the set value may be determined to be within a range of 0.5 to 0.6.

[0184] Although a lower heat exchange index value of the condenser means a higher heat exchange performance of the condenser, if the index value is too low, it can be understood that some cause has occurred that causes the cycle to deviate from the normal range. For example, the cause may be a failure or abnormal operation of a sensor or pump.

[0185] If the heat exchange index value of the condenser is equal to or less than a set value, collection of operational data is stopped.

[0186] A third event is when the hot gas valve 171 is turned on and opened. When the hot gas valve 171 is turned on and opened, collection of operating data can be stopped.

[0187] When the cooling load required by the chiller 10 is not large, the hot gas valve 171 is opened, and the refrigerant in the high-pressure condenser 120 can flow to the low-pressure evaporator 140 through the open hot gas valve 171. Therefore, the condensation capacity of the condenser 120 is low, and the refrigerant temperature of the condenser or the outlet temperature of the cooling water passing through the condenser 120 can be maintained at a relatively low temperature.

[0188] As described above, in the operation mode in which the hot gas valve 171 is opened, the temperature and pressure ranges are outside those of a typical cycle, so that it is difficult to accurately determine the degree of contamination of the condenser heat transfer tube.

[0189] A fourth event is when the difference between the inlet water temperature and the outlet water temperature of the condenser 120 becomes equal to or greater than a set value. When the difference between the inlet water temperature and the outlet water temperature of the condenser 120 becomes equal to or greater than a set value, collection of operation data can be stopped.

[0190] If the difference between the inlet and outlet water temperatures of the condenser 120 exceeds a preset value, it can be understood that some cause has occurred that has caused the cycle to deviate from its normal operating range. For example, the cause may be a failure or abnormal operation of a sensor or pump.

[0191] When any one of the first to fourth events occurs, collection of driving data can be stopped for the time that the event is maintained (S16).

[0192] On the other hand, if such an event does not occur, information on the heat exchange capacity index for determining the degree of contamination of the condenser heat transfer tube can be obtained and stored in the memory unit 270. That is, the heat exchange capacity index value of the condenser can be recognized by using the difference between the refrigerant temperature of the condenser and the outlet temperature of the cooling water (S17).

[0193] The heat exchange capacity index value of the condenser can be calculated in real time while the current cycle is maintained, or can be calculated at a specific time point (for example, exactly every hour) and stored in the memory unit 270. Through this process, the memory unit 270 accumulates the operating data of the previous cycle and updates the operating data of the current cycle (S18).

[0194] From the data accumulated in this manner, the average value of the heat exchange performance index value of the condenser 120 or the amount of change therein is calculated (S19).

[0195] In particular, the controller 200 may calculate an average value of the collected driving data for multiple driving cycles. By way of example, the average value may be an average value for each driving cycle or an aggregate average value for two or more driving cycles.

[0196] To implement a simple control logic, for example, the controller may calculate an average value for a number of operating cycles corresponding to one month.

[0197] The controller 200 may calculate a change amount of the calculated average values. As an example, the controller may calculate the change amount based on a first average value of the driving data corresponding to the first month, a second average value of the driving data corresponding to the next month, and a third average value of the driving data corresponding to the month thereafter.

[0198] As an example, such mean and mean change calculations may be performed over a period of 6 to 12 months.

[0199] The controller 200 can recognize the degree of contamination of the heat transfer tube of the condenser based on the average value or the amount of change in the average value. That is, the average value or the amount of change in the average value is compared with a set value (S20).

[0200] For example, when the number of times that the average value is recognized to be equal to or greater than a first set value is equal to or greater than a set number of times, it can be recognized that an excessive amount of foreign matter is contained in the heat transfer tube of the condenser. For example, the first set value may be 3 degrees, and the set number of times may be 3 or more.

[0201] As another example, when it is recognized that the amount of change in the average value per period is equal to or greater than a second set value, the controller 200 may recognize that an excessive amount of foreign matter is included in the heat transfer tube of the condenser. For example, the second set value may be 2 degrees (S21, S22).

[0202] If the controller 200 determines that an excessive amount of foreign matter is present in the heat transfer tube of the condenser, it can display information regarding the degree of contamination of the heat transfer tube through the display unit 250 or output an alarm notifying the user that the heat transfer tube needs to be cleaned (S23).

[0203] According to this control method, operating data that indicates that contamination has occurred in the condenser heat transfer tube during operation of the chiller 10 can be accurately analyzed, and based on the analysis results, information on the level of contamination or a notice that the heat transfer tube needs to be cleaned can be provided to the user, thereby increasing user convenience and improving system management efficiency.

Claims

1. A cooling tower that stores cooling water for heat exchange with outside air; a condenser including a heat transfer tube through which the cooling water supplied from the cooling tower flows and into which a refrigerant flows to exchange heat with the cooling water of the heat transfer tube; a cooling water outlet temperature sensor provided in a cooling water outlet pipe for discharging cooling water from the condenser, the cooling water outlet temperature sensor detecting a temperature of the discharged cooling water; a condenser pressure sensor provided inside the condenser for detecting a refrigerant pressure inside the condenser; a condenser level sensor for detecting a water level of the refrigerant stored in the condenser; a controller that collects operational data by calculating a difference between a temperature value detected by the cooling water outlet temperature sensor and a refrigerant temperature value converted from a refrigerant pressure value detected by the condenser pressure sensor, and recognizes a contamination level of the cooling water caused by deposition of foreign matter on a heat transfer tube of the condenser; a display unit that outputs information about the contamination level when it is determined that the information about the difference value is outside a preset value, When the controller recognizes in the process of recognizing the degree of contamination that the value detected by the condenser level sensor is equal to or higher than a set value, the controller controls the chiller to stop collecting the operating data.

2. The method further includes a memory unit that updates and stores information about the difference value for each operation cycle, The chiller according to claim 1 , wherein the controller calculates an average value of a plurality of difference values ​​for a plurality of operation cycles stored in the memory unit.

3. The controller:

3. The chiller of claim 2, wherein when it is determined that the number of times that the average value is recognized to be equal to or greater than a predetermined first set value is equal to or greater than a set number of times, information regarding the degree of contamination of the heat transfer tube is output to the display unit.

4. The controller: The chiller according to claim 2 , wherein when it is determined that an amount of change in the average value for each of the plurality of operating cycles is equal to or greater than a second set value, information regarding the degree of contamination of the heat transfer tube is output to the display unit.

5. The controller: The chiller of claim 1 , wherein the collection of the operating data is stopped when it is recognized that the difference between the temperature value detected by the cooling water outlet temperature sensor and the refrigerant temperature value converted by the condenser pressure sensor is equal to or less than a set value.

6. an expansion device for reducing the pressure of the refrigerant condensed in the condenser; an evaporator that evaporates the refrigerant decompressed by the expansion device; The chiller of claim 1 , further comprising: a hot gas valve installed in a connecting pipe connecting the condenser and the evaporator, the hot gas valve being opened to bypass the refrigerant inside the condenser to the evaporator.

7. The controller: The chiller of claim 6 , wherein the collection of the operational data is discontinued when the hot gas valve is recognized to be open.

8. a cooling water inlet temperature sensor provided in a cooling water inlet pipe for inflowing cooling water into the condenser and detecting a temperature of the inflowing cooling water; The controller: The chiller according to claim 1 , wherein when it is recognized that a difference between the inlet water temperature and the outlet water temperature of the condenser is equal to or greater than a set value, collection of the operating data is stopped.

9. The condenser further includes a water box provided on both sides of the heat transfer tube of the condenser to provide a flow space through which cooling water flows, The chiller of claim 1 , wherein the cooling water outlet piping is coupled to the water box.

10. The water box includes a first water box to which the cooling water outlet pipe is coupled, and a second water box provided on an opposite side of the first water box, 10. The chiller of claim 9, wherein a partition plate is provided inside the first water box to partition a first space for introducing cooling water into the inside of the condenser and a second space for discharging the cooling water that has been heat exchanged in the condenser.

11. the heat transfer tube of the condenser includes a first heat transfer tube and a second heat transfer tube separated by a separation plate; The chiller according to claim 1 , wherein flow holes are formed between the separation plate and both ends of the condenser to guide the refrigerant that has undergone heat exchange in the first heat transfer tube to the second heat transfer tube.

12. a refrigerant inlet for injecting a refrigerant into the condenser; The chiller of claim 1 , further comprising: a guide plate provided inside the condenser and disposed adjacent to the refrigerant inlet, against which the refrigerant flowing in through the refrigerant inlet hits.

13. 1. A method for controlling a chiller, comprising: The chiller comprises: A cooling tower that stores cooling water for heat exchange with outside air; a condenser including a heat transfer tube through which the cooling water supplied from the cooling tower flows and into which a refrigerant flows to exchange heat with the cooling water of the heat transfer tube; a cooling water outlet temperature sensor provided in a cooling water outlet pipe for discharging cooling water from the condenser, the cooling water outlet temperature sensor detecting a temperature of the discharged cooling water; a condenser pressure sensor for detecting a refrigerant pressure inside the condenser; a condenser level sensor for detecting a water level of the refrigerant stored in the condenser; Including, The chiller control method includes: A step of collecting operation data by calculating a difference value between a temperature value detected by the cooling water outlet temperature sensor and a refrigerant temperature value converted from a refrigerant pressure value detected by the condenser pressure sensor by a controller; and when the controller recognizes that the information about the difference value is outside a preset value, outputting information about a contamination level of the cooling water caused by deposition of foreign matter in the heat transfer tube of the condenser to a display unit, The chiller control method, wherein when the controller recognizes, in the process of recognizing the degree of contamination, that the value detected by the condenser level sensor is equal to or higher than a set value, the controller controls to stop collecting the operating data.

14. The chiller further includes a memory unit that updates and stores information regarding the difference value for each operation cycle, The chiller control method according to claim 13 , wherein the controller calculates an average value of a plurality of difference values ​​for a plurality of operation cycles stored in the memory unit.

15. The controller:

15. The chiller control method of claim 14, wherein when it is recognized that the number of times that the average value is recognized to be equal to or greater than a first set value is equal to or greater than a set number of times, or when it is recognized that an amount of change in the average value for each of the plurality of operating cycles is equal to or greater than a second set value, information regarding the degree of contamination of the heat transfer tube is output to the display unit.

16. The controller: When a preset event occurs during the process of recognizing the degree of contamination, the process of calculating the difference value and collecting the operation data is stopped; The preset event is: a first event that recognizes that the water level value detected by the condenser level sensor is equal to or greater than a set value; a second event that recognizes that a difference between the temperature value detected by the cooling water outlet temperature sensor and the refrigerant temperature value converted by the condenser pressure sensor is equal to or smaller than a set value; a third event recognizing that a hot gas valve has been opened to bypass the refrigerant in the condenser to the evaporator; and The method for controlling a chiller according to claim 13, further comprising at least one fourth event that recognizes that a difference between the inlet water temperature and the outlet water temperature of the condenser is equal to or greater than a set value.

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