Receiver for a cooling system
By using a PTC heater and controller in the cooling system receiver, the problem of the complexity of manually winding the heating tape is solved, achieving simplified installation and efficient heating, and adapting to changes in cooling system pressure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SCHNEIDER ELECTRIC IT CORP
- Filing Date
- 2019-02-28
- Publication Date
- 2026-05-12
AI Technical Summary
In the prior art, the heating tape used for the receiver of the heating and cooling system needs to be manually wrapped, which is complicated and not efficient enough.
The system uses a polymer positive temperature coefficient heating element (PTC heater), and the heater wires are controlled by a controller. The wires are directly inserted into the heater well and sealed with a strain relief plug, simplifying the installation process.
It reduces installation time and cost, and improves heating efficiency and ease of operation.
Smart Images
Figure CN116972554B_ABST
Abstract
Description
[0001] This application is a divisional application of the application filed on February 28, 2019, with application number 201910152109.X and invention title "Receiver for Cooling System".
[0002] Public background
[0003] 1. Public domain
[0004] The technical field generally relates to cooling systems, and more specifically to receivers for cooling systems that include heating elements.
[0005] 2. Discussion of related technologies
[0006] Economical heat dissipation systems can combine different methods for removing heat from indoor spaces (such as computer rooms or data centers). For example, different carrying liquids and cooling devices can be used to facilitate heat exchange between indoor and outdoor spaces.
[0007] An example of a heat dissipation method combines an air-cooled computer room air conditioner (CRAC) with a condenser, and is often referred to as an air-cooled CRAC DX system. The name "DX" stands for direct expansion and refers to any system that uses refrigerant and evaporator coils to produce a cooling effect. The refrigerant can be a chlorinated fluorocarbon, a halogenated chlorofluorocarbon, or ammonia. Air-cooled CRAC units are used in IT environments and are typically configured such that half of the components of the refrigeration cycle are in the CRAC and the remaining components are outdoors in an air-cooled condenser. Heat from the IT environment is "pumped" to the outdoor environment using the refrigerant circulation flow. The compressor can be located either in the CRAC unit or in the condenser.
[0008] Free cooling refers to cooling technologies that use low outside air temperatures to aid in cooling operations. When atmospheric conditions permit, air-side free cooling introduces cool outside air directly into the IT room or data center. Water-side free cooling uses additional cooling coils containing ethylene glycol, which circulates directly from the fluid cooler when atmospheric conditions allow. Free cooling methods can be direct or indirect. Direct free cooling refers to a cooling technology that directly mixes air from the external environment (e.g., outdoors) with hot air from the internal environment (e.g., rooms within a building). Conversely, indirect free cooling refers to a cooling technology that indirectly mixes air from the external environment with hot air from the internal environment. An example of indirect free cooling combines air ducts with an indirect air evaporative cooler. When the outside temperature is below the IT environment's inlet air temperature setpoint, the system uses outside air as a heat-carrying fluid to indirectly cool the data center air. Fans blow cool outside air through an air-to-air heat exchanger, which in turn cools the hot data center air on the other side of the heat exchanger, thus completely isolating the data center air from the outside air.
[0009] One or more heat dissipation methods can be used to cool computer rooms or data center environments. The main difference between heat dissipation methods may lie in how each method collects heat and transfers it to the outside atmosphere. When combined, these differences can sometimes lead to one or more mechanical problems and increased energy consumption.
[0010] This DX cooling system includes several components, including a receiver that is supplied with a heat transfer fluid, such as R-134a coolant, used in the cooling system for operating the DX condenser. The liquid receiver can be configured to store at least a portion of the coolant according to pressure fluctuations in the cooling system and can function to allow the heat exchanger to overflow using an overflow valve. The overflow valve functions to maintain a stable or minimum liquid pressure and / or temperature of the coolant in the cooling system. In one embodiment, the receiver collects coolant when the pressure in the DX cooling system is low. Therefore, heating the coolant in the receiver to increase the suction pressure may be necessary. In one embodiment, a heating band can be applied to the outer surface of the receiver using a zipper strap. This known method of heating the coolant in the receiver... Figure 1 As shown, receiver 1 has a heating band 2 installed at the customer's line of sight, and the insulation around the receiver needs to be removed. A more complex and efficient method is required to heat the coolant.
[0011] Public Overview
[0012] One aspect of this disclosure relates to a receiver for a cooling unit. In one embodiment, the receiver includes a cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall. The receiver also includes an inlet disposed in the cylindrical body, an outlet disposed in the cylindrical body, a heater well disposed within the cylindrical body, and a heater located in the heater well for selectively heating a heat transfer fluid contained within the inner cavity of the cylindrical body.
[0013] Embodiments of the receiver may further include positioning the heater well along an axis coaxial with the axis of the cylindrical wall of the cylindrical body, extending from the top wall to an adjacent bottom wall. The heater may be located at the bottom of the heater well. The heater may extend horizontally adjacent to the bottom wall of the cylindrical body. The heater may be a polymeric positive temperature coefficient heating element. The receiver may further include heater wires connected to the heater and configured to supply power to the heater. The heater wires may be connected to a controller configured to control the operation of the heater. The receiver may further include a strain relief plug configured to seal the heater well. An inlet may be located in the top wall, and an outlet may be located in the top wall.
[0014] Another aspect of this disclosure relates to a method for selectively heating a heat transfer fluid in a receiver of a cooling unit. In one embodiment, the method includes: providing a receiver comprising a cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall, an inlet disposed in the cylindrical body, an outlet disposed in the cylindrical body, and a heater well disposed within the cylindrical body; positioning a heater in the heater well; and selectively powering the heater to heat the heat transfer fluid contained in the receiver.
[0015] Embodiments of the method may further include positioning a heater well extending from a top wall to an adjacent bottom wall along an axis coaxial with the cylindrical wall of the cylindrical body. The heater may be located at the bottom of the heater well. The heater may extend horizontally adjacent to the bottom wall of the cylindrical body. The heater may be a polymeric positive temperature coefficient heating element. The method may further include connecting the heater to heater wiring to supply power to the heater. The method may further include connecting the heater wiring to a controller configured to control the operation of the heater. The method may further include sealing the heater well with a strain-relieving plug configured to seal the heater well. An inlet may be located in the top wall, and an outlet may be located in the top wall.
[0016] In another aspect, a cooling unit includes a housing, a compressor supported by the housing, a condenser supported by the housing and in fluid communication with the compressor, and a receiver supported by the housing and in fluid communication with the compressor and the condenser. The receiver includes a cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall. The receiver also includes an inlet disposed in the cylindrical body, an outlet disposed in the cylindrical body, a heater well disposed within the cylindrical body, a heater positioned in the heater well, and heater wires connected to and configured to supply power to the heater. The heater wires are connected to a controller configured to control the operation of the heater to selectively heat the heat transfer fluid contained within the inner cavity of the cylindrical body. The receiver also includes a strain relief plug configured to seal the heater well.
[0017] Embodiments of the cooling unit may further include positioning a heater well extending from the top wall to an adjacent bottom wall along an axis coaxial with the axis of the cylindrical wall of the cylindrical body. The heater may be located at the bottom of the heater well, and the heater is a polymer positive temperature coefficient heating element.
[0018] Other aspects, embodiments, and advantages of these exemplary aspects and embodiments will be discussed in detail below. Furthermore, it should be understood that the above information and the following detailed description are merely illustrative examples of various aspects and embodiments, and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed aspects and embodiments. The embodiments disclosed herein may be combined with other embodiments, and references to “embodiment,” “example,” “some embodiments,” “some examples,” “alternative embodiments,” “various embodiments,” “one embodiment,” “at least one embodiment,” “this and other embodiments,” “certain embodiments,” or similar terms are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one embodiment. The appearance of such terms herein does not necessarily refer to the same embodiment. Attached Figure Description
[0019] Various aspects of at least one embodiment are discussed below with reference to the accompanying drawings, which are not intended to be drawn to scale. The drawings are included to provide illustration and further understanding of various aspects and embodiments, and are incorporated in and constitute a part of this specification, but are not intended to be limiting of any particular embodiment. The drawings, together with the remainder of the specification, serve to explain the principles and operation of the described and claimed aspects and embodiments. In the drawings, each identical or substantially identical component shown in different figures is represented by similar numbers. For clarity, not every component is labeled in every drawing. In the drawings:
[0020] Figure 1This is a view of a conventional receiver in the prior art, which has a heating band applied thereto;
[0021] Figure 2 This is a perspective view of a cooling unit with a receiver according to an embodiment of this disclosure;
[0022] Figure 3 yes Figure 2 A perspective view of the receiver shown;
[0023] Figure 4 It is a perspective view of the receiver, showing that the cylindrical walls of the receiver are translucent to reveal the interior of the receiver;
[0024] Figure 5 This is a cross-sectional view of the receiver;
[0025] Figure 6 This is a perspective view of the receiver.
[0026] Figure 7 This is a perspective view of a receiver according to another embodiment of this disclosure; and
[0027] Figure 8 yes Figure 7 The receiver shown is a cross-sectional view. Detailed description
[0028] Cooling systems used to dissipate heat in regulated spaces such as IT environments use heat transfer fluids such as air, water, or refrigerant to transfer heat from indoors to outdoors. Many cooling systems rely on a refrigeration cycle as the primary means of cooling. Pumped refrigerant systems provide isolation between the main heat dissipation system and IT equipment. Direct-air and indirect-air methods rely on outdoor conditions as the primary means of cooling, making them more effective in mild climates.
[0029] In some embodiments, the space being cooled is a data center or IT environment. A data center may include one or more rooms or spaces containing rows of equipment racks designed to house electronic devices, such as data processing, networking, and telecommunications equipment. During operation, the electronic devices generate heat, which needs to be dissipated to ensure the continued performance, reliability, and lifespan of the equipment components housed in the equipment racks. One or more embodiments of the systems disclosed herein are designed to dissipate the heat generated by the electronic devices within the data center and return cool air to the data center.
[0030] An example of a method for heat dissipation in an IT environment includes a cooling system with a DX cooling unit. In this type of system, the refrigeration cycle components can be located within a housing outside the space being cooled, and a heat exchanger can be located within the space being cooled. This heat exchanger uses refrigerant to collect heat from the DX cooling unit and transfer it away from the IT environment. (See reference...) Figure 2 The diagram illustrates an example of a cooling system including a DX cooling unit, typically indicated at 10. The DX cooling unit 10 includes a housing 12, a compressor 14, a fan unit 16, a DX condenser indicated by dashed line 18, and a receiver typically indicated at 20. The DX condenser 18 of the DX cooling unit is shown in dashed lines to illustrate a key component of the unit, including the receiver 20. As described above, the receiver 20 is a container for storing the heat transfer fluid used in the DX cooling unit 10 for operating the DX condenser 18. The receiver 20 can be configured to store at least a portion of the heat transfer fluid according to pressure fluctuations in the cooling system. Although in Figure 2 Although not explicitly shown, the DX cooling system 10 also includes one or more pumps or compressors for pumping heat transfer fluid within the DX cooling unit.
[0031] The DX cooling system 10 may also include a controller 22 that functions to control one or more components of the DX cooling unit 20. For example, the controller 22 may control one or more operating parameters of the compressor 14, the DX condenser 18, and other components of the unit 10 (including the receiver 20). A sensor (not shown) may be located in the DX cooling system 10 and configured to measure operating parameters such as flow rate, temperature, and pressure. The sensor may send an input signal to the controller 22, which then uses the input signal to control the components of the DX cooling system 10. For example, the sensor may be used to control the components of the DX cooling unit 10 in one or more operating modes.
[0032] Reference Figure 3 and Figure 4 The receiver 20 includes a cylindrical body 24 made of a suitable metal (e.g., stainless steel). The cylindrical body 24 includes a cylindrical wall 26, a curved top wall 28 disposed at the top of the cylindrical wall, and a curved bottom wall 30 disposed at the bottom of the cylindrical wall. In one embodiment, the top wall 28 and the bottom wall 30 are dome-shaped or spherical. The cylindrical wall 26, the top wall 28, and the bottom wall 30 together define an inner cavity 32 designed to accommodate and store the heat transfer fluid 34. Figure 5 As mentioned above, receiver 20 is designed to receive, store, and transport heat transfer fluids, such as R-134a coolant.
[0033] As shown, the cylindrical wall 26 includes two brackets, each indicated at 36, for securing the receiver 20 to a component of the DX cooling unit 10, such as the housing of the compressor 14. The cylindrical wall 26 also includes three ports for indicating the refrigerant level, each indicated at 38. The cylindrical body 24 is mounted on a base 40, which is configured to... Figure 2-6 The cylindrical body supporting the receiver 20 in the vertical position shown. In one embodiment, the base 40 is mounted on the bottom of the housing 12 of the DX cooling unit 10 or otherwise fixed to the bottom of the housing 12.
[0034] For further reference Figure 5 and Figure 6 The top wall 28 of the cylindrical body 24 includes an inlet 42 for delivering heat transfer fluid into the inner cavity 32 of the cylindrical body. The cylindrical body 24 also includes an outlet 44 for removing heat transfer fluid from the inner cavity 32 of the cylindrical body. Specifically, the inlet 42 is configured to receive heat transfer fluid from the DX condenser 18 of the DX cooling unit 10, and the outlet 44 is configured to deliver heat transfer fluid to the DX condenser via the compressor 14. The receiver 20 functions as a reservoir for storing the heat transfer fluid used in the DX cooling unit 10 for operating the DX condenser 18. The receiver 20 stores at least a portion of the heat transfer fluid 34 according to pressure fluctuations in the DX cooling unit 10. The top wall 28 also includes a port 46 configured for installing a safety valve to release pressure when the pressure within the receiver 20 becomes too high.
[0035] like Figure 5 As shown, receiver 20 also includes a heater well 48 formed to extend along the length of cylindrical body 24 of receiver 20. In the illustrated embodiment, heater well 48 extends along a longitudinal axis A coaxial with the axis of cylindrical body 24. Heater well 48 extends from top wall 28 of cylindrical body 24 toward bottom wall 30 of cylindrical body, such that the bottom of heater well is adjacent to bottom wall. Heater well 48 is blinded because it is completely enclosed by cylindrical body 24. It should be understood that the diameter of heater well 48 may vary based on the size and shape of heating elements arranged within heater well.
[0036] Receiver 20 also includes a heater 50 located within heater well 48. As shown, in one embodiment, heater 50 is located at the bottom of heater well 48. However, heater 50 can be located anywhere along the length of heater well 48. Heater 50 can be any type of heating element configured to rapidly heat the heat transfer fluid 34 housed within the cavity 32 of the cylindrical body 24 of receiver 20. In one embodiment, heater 50 is a polymer positive temperature coefficient (“PTC”) heating element. PTC heaters operate at lower temperatures (e.g., 500°F) to provide a safer, more durable, and cost-effective method for heating the heat transfer fluid 34 disposed within the cavity 32 of receiver 20. Electricity is delivered to heater 50 via heater wires or cables 52 connected to the heater. In one embodiment, heater wires 52 are coupled to a controller 22 configured to control the operation of heater 50. In one embodiment, when the DX cooling unit 10 is in standby mode, the controller 22 is configured to energize the heater 50 to heat the heat transfer fluid 34 contained in the cavity 32 of the cylindrical body 24 of the receiver 20, and when the DX cooling unit is in operation, the controller is configured to de-energize the heater.
[0037] The heater 50 is protected from external materials entering the heater well 48 by a strain relief plug 54 configured to seal the heater well. As shown, the strain relief plug 54 surrounds the upper end of the heater well 48 while allowing the heater wires 52 to pass through it. In some embodiments, the strain relief plug 54 is made of metal or plastic material.
[0038] Reference Figure 7 and Figure 8 In another embodiment of this disclosure, the receiver is typically indicated at 70. Like receiver 20, receiver 70 includes a cylindrical body 24 having a cylindrical wall 26, a curved top wall 28 disposed at the top of the cylindrical wall, and a curved bottom wall 30 disposed at the bottom of the cylindrical wall. The cylindrical wall 26, top wall 28, and bottom wall 30 together define an inner cavity 32 designed to accommodate and store heat transfer fluid 34. Figure 8As shown, the cylindrical wall 26 includes two brackets, each indicated at 36, for securing the receiver 70 to a component of the DX cooling unit 10, such as the housing of the compressor 14. The cylindrical wall 26 also includes three ports provided for indicating the refrigerant level, each indicated at 38. A cylindrical body 24 is mounted on a base 40 configured to support the cylindrical body of the receiver 70 in a vertical position. The top wall 28 of the cylindrical body 24 includes an inlet 42 for delivering heat transfer fluid into the inner cavity 32 of the cylindrical body. The cylindrical body 24 also includes an outlet 44 for removing heat transfer fluid from the inner cavity 32 of the cylindrical body. The top wall 28 also includes a port 46 configured for mounting a safety valve to release pressure when the pressure within the receiver 70 becomes too high.
[0039] As in Figure 5 As best shown, the receiver 70 also includes a heater well 72 formed to extend horizontally adjacent to the bottom wall 30 of the cylindrical body 24. In the illustrated embodiment, the heater well 72 extends along the longitudinal axis B. The heater well 72 is blind because it is completely enclosed by the cylindrical body 24. It should be understood that the diameter of the heater well 72 may vary based on the size and shape of the heating elements arranged within the heater well.
[0040] The receiver 70 also includes a heater 74 located within the heater well 72. Like the heater 50, the heater 74 can be any type of heating element configured to rapidly heat the heat transfer fluid 34 contained within the cavity 32 of the cylindrical body 24 of the receiver 70. Electricity is delivered to the heater 74 via a heater wire or cable 76 connected to the heater. In one embodiment, the heater wire 76 is coupled to a controller 22 configured to control the operation of the heater 74. In one embodiment, the controller 22 is configured to energize the heater 74 to heat the heat transfer fluid 34 contained within the cavity 32 of the cylindrical body 24 of the receiver 70 when the DX cooling unit 10 is in standby mode, and to de-energize the heater when the DX cooling unit is operating. Like the heater 50, the heater 74 can be protected from external materials entering the heater well 72 by a strain relief plug (not shown) configured to seal the heater well.
[0041] As described herein, the receiver of embodiments of this disclosure provides a heater solution that reduces installation time and cost because maintenance technicians installing the receiver do not need to wrap heating tape around the receiver. The technician simply inserts the heater into the heater well and connects the power cord to the controller. The blind well is then sealed by installing a strain relief plug. Therefore, the heat generated by the heater is absorbed by a heat transfer fluid contained within the inner cavity of the cylindrical body of the receiver.
[0042] The aspects of the invention disclosed herein are not limited in their application to the details of the construction and arrangement of components set forth in the following description or shown in the accompanying drawings. Other embodiments are contemplated and can be practiced or performed in various ways. Examples of specific implementations are provided herein for illustrative purposes only and are not intended to be limiting. In particular, actions, components, elements, and features discussed in connection with any one or more embodiments are not intended to exclude similar roles in any other embodiments.
[0043] Furthermore, the wording and terminology used herein are for descriptive purposes and should not be considered restrictive. Any reference to examples, embodiments, components, elements, or actions of systems and methods mentioned herein in the singular may also include plural embodiments, and any reference to any embodiment, component, element, or action mentioned herein in the plural may also include only the singular embodiments. References in the singular or plural form are not intended to limit the currently disclosed systems or methods, their components, actions, or elements. The terms “including,” “comprising,” “having,” “comprising,” and “involving,” and their variations, as used herein, are intended to include the items listed thereafter and their equivalents, as well as additional items. References to “or” may be construed as inclusive, such that any item described using “or” may refer to any one, more than one, or all of the described items. Additionally, in the event of inconsistencies in terminology between this document and documents incorporated herein by reference, the terminology used in the incorporated references shall supplement the terminology used in this document; in the case of irreconcilable inconsistencies, the terminology used in this document shall prevail.
[0044] Having described several aspects of at least one example, it should be appreciated that various changes, modifications, and improvements will readily occur to those skilled in the art. For example, the examples disclosed herein can also be used in other contexts. Such changes, modifications, and improvements are intended to be part of this disclosure and are intended to be within the scope of the examples discussed herein. Therefore, the foregoing description and figures are merely illustrative.
Claims
1. A receiver for a cooling unit, the receiver comprising: A cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall; The entrance is located within the cylindrical body; The outlet is located within the cylindrical body. A heater well, which is located within the cylindrical body; as well as A heater, positioned within the heater well, selectively heats the heat transfer fluid contained within the inner cavity of the cylindrical body. The heater well extends horizontally adjacent to the bottom wall of the cylindrical body along an axis substantially perpendicular to the axis of the cylindrical wall of the cylindrical body. The heater is configured to be coupled to a controller, and The controller is configured to control the operation of the heater in such a way that when the cooling unit is in standby mode, the controller is configured to energize the heater to heat the heat transfer fluid contained in the inner cavity of the cylindrical body of the receiver, and when the cooling unit is in operation, the controller is configured to de-energize the heater.
2. The receiver according to claim 1, wherein, The heater is a polymer positive temperature coefficient heating element.
3. The receiver of claim 1 further includes a strain relief plug configured to seal the heater well.
4. The receiver of claim 1 further includes a heater wire connected to the heater, the heater wire being configured to supply power to the heater.
5. The receiver according to claim 4, wherein, The heater wires are connected to a controller configured to control the operation of the heater.
6. The receiver according to claim 1, wherein, The inlet is located in the top wall, and the outlet is located in the top wall.
7. The receiver according to claim 1, wherein, The heater well is completely enclosed by the cylindrical body.
8. A method for selectively heating a heat transfer fluid in a receiver of a cooling unit, the method comprising: A receiver is provided, the receiver comprising a cylindrical body, an inlet disposed in the cylindrical body, an outlet disposed in the cylindrical body, and a heater well positioned within the cylindrical body, the cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall; Position the heater in the heater well; as well as The heater is selectively powered to heat the heat transfer fluid contained in the receiver. The heater well extends horizontally adjacent to the bottom wall of the cylindrical body along an axis substantially perpendicular to the cylindrical wall of the cylindrical body. The heater is configured to be coupled to the controller; and The method further includes controlling the operation of the heater in such a way that when the cooling unit is in standby mode, the controller is configured to energize the heater to heat the heat transfer fluid contained in the inner cavity of the cylindrical body of the receiver, and when the cooling unit is in operation, the controller is configured to de-energize the heater.
9. The method according to claim 8, wherein, The heater is a polymer positive temperature coefficient heating element.
10. The method of claim 8, further comprising connecting the heater to heater wires to supply power to the heater.
11. The method of claim 10, further comprising connecting the heater wires to the controller.
12. The method of claim 8, further comprising sealing the heater well with a strain relief plug configured to seal the heater well.
13. The method according to claim 8, wherein, The inlet is located in the top wall, and the outlet is located in the top wall.
14. A cooling unit, comprising: case; The compressor is supported by the housing; A condenser, which is supported by the housing and is in fluid communication with the compressor; as well as A receiver, supported by the housing and in fluid communication with the compressor and the condenser, comprises: A cylindrical body having a cylindrical wall defining an inner cavity, a bottom wall formed together with the cylindrical wall, and a top wall formed together with the cylindrical wall. The entrance is located within the cylindrical body. The outlet is located within the cylindrical body. The heater well is located within the cylindrical body, and A heater, positioned within the heater well, selectively heats the heat transfer fluid contained within the inner cavity of the cylindrical body. The heater well extends horizontally adjacent to the bottom wall of the cylindrical body along an axis substantially perpendicular to the axis of the cylindrical wall of the cylindrical body. The receiver further includes a heater wire connected to and configured to supply power to the heater, the heater wire being connected to a controller configured to control the operation of the heater to selectively heat the heat transfer fluid contained within the inner cavity of the cylindrical body. The controller is configured to control the operation of the heater in such a way that when the cooling unit is in standby mode, the controller is configured to energize the heater to heat the heat transfer fluid contained in the inner cavity of the cylindrical body of the receiver, and when the cooling unit is in operation, the controller is configured to de-energize the heater.
15. The cooling unit according to claim 14, wherein, The receiver also includes a strain relief plug configured to seal the heater well.