Patent Publication Number: US-2023151905-A1

Title: Automatization of drainage and deaerators

Description:
FIELD OF THE INVENTION 
     The invention relates to automatization of drainage or deaeration of a hydraulic system. 
     BACKGROUND OF THE INVENTION 
     Hydraulic systems, e.g. district heating or district cooling systems and other closed loop liquid based energy distributed grids in need of drainage or deaeration, are equipped with low points and high points, wherein the low points are located in the lowest parts of the system and the high points are located in the highest parts of the system. In the low points, fluid may accumulate, and in the high points, air may accumulate. Therefore, in the low points, the fluid may be diverted. i.e. drainage may be performed, and in the high points, the air may be diverted, i.e. deaeration may be performed. 
     Today, drainage and deaeration of a hydraulic system is typically performed manually by operators. A drawback with this solution is that the operators need to travel from one point to another in order to drainage or deaeration of the hydraulic system. The hydraulic systems can be large in size and the drainage or deaeration points can be located at a distance from each other, both in an area perspective but also in a height perspective. Further, drainage or deaeration usually needs to be repeated several times before it is completed. Moreover, poorly completed drainage can provide for scalding for people working with the system and poorly completed deaeration can provide for that air will circulate within the system which can lead to damages and bad function of e.g. pumps in the hydraulic system. 
     Even if it is known how to drainage or deaeration of the hydraulic system, these solutions can be further improved. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to solve at least some of the problems mentioned above. 
     According to a first aspect, a valve assembly for drainage or deaeration of a hydraulic system is provided. The valve assembly comprising a valve, a valve assembly controller and a sensor. The valve comprising a first side and a second side. The first side is configured to be connected to the hydraulic system. The second side is connected to a mouth piece. The valve is configured to be set in an open state or in a closed state. Upon the valve is set in the open state, fluid in the hydraulic system is free to pass the valve from the first side to the second side. The valve assembly controller comprising a transceiver and a valve assembly control circuit. The transceiver is configured to receive a control signal indicating a start of drainage or deaeration of the hydraulic system. The valve assembly control circuit is configured to execute a valve control function and a drainage or deaeration function. The valve control function is configured to set the valve in the open state or in the closed state. The drainage or deaeration function is configured to, based on the control signal, instruct the valve control function to set the valve in the open state. The sensor is configured to monitor the mouth piece to obtain sensor data pertaining to a type of fluid leaving the mouth piece upon the valve is set in the open state, wherein the type of fluid is heat transfer fluid of the hydraulic system or air. 
     By the present valve assembly, the drainage or deaeration in the hydraulic system may be remotely controlled. Hence, an operator does not need to travel between the different drainage or deaeration points within the hydraulic system, instead, the drainage or deaeration can be done in a remote way by using the valve assembly controller and the sensor in combination. The sensor may be configured to work as the operator&#39;s senses, e.g. eyes and/or ears, in order to monitor the drainage or deaeration. 
     By the present valve assembly, a more accurate and efficient solution for drainage or deaeration of the hydraulic system may be achieved. Thus, by the present valve assembly, it may not be the operator&#39;s experience that will determine whether the drainage or deaeration is completed or not, but analysis of sensor data from the sensor that monitors the mouth piece. Further, the present valve assembly may not only be used when the system needs to be drainage or deaeration, but also when the valves need to be exercised. Thus, the valves need to be exercised every now and then in order to be in good condition. In addition, the valves constitute weak points within the hydraulic system and by the present valve assembly, these can be controlled in a better and more efficient way. 
     Further, by using the present valve assembly, the drainage or deaeration of the hydraulic system may be performed during a shorter period of time compared to if manually drainage or deaeration the hydraulic system. Thus, by spending less time on drainage or deaeration of the hydraulic system, the hydraulic system may be operational for longer time periods. 
     The sensor may comprise a camera configured to capture images of the mouth piece. 
     The sensor may further comprise an illuminator configured to illuminate the mouth piece. 
     The sensor may comprise a microphone. 
     The sensor may comprise a tactile sensor. The tactile sensor may be configured to detect whether fluid is present in the mouth piece. 
     The sensor may comprise an electric sensor. The sensor may comprise a magnetic sensor. 
     The sensor may comprise a detection means. The detection means may be configured to detect a trace element. The trace element may be blended in the fluid. The trace element may be added in the hydraulic system. 
     The sensor may be configured to be set in a sleeping mode or in a monitoring mode. 
     The valve assembly control circuit may further be configured to execute a sensor control function configured to set the sensor in the sleeping mode or the monitoring mode. The drainage or deaeration function may further be configured to, based on the control signal, instruct the sensor control function to set the sensor in the monitoring mode. 
     The transceiver may be configured to transmit the sensor data. 
     The valve assembly control circuit may further be configured to execute an analyze function configured to analyze the sensor data in order to determine whether the drainage or deaeration of the hydraulic system may be completed. The analysis may be performed by running the sensor data through a neural network that may be trained to determine whether the drainage or deaeration is completed. 
     The analyze function may further be configured to, upon the analyze function has concluded that the drainage or deaeration of the hydraulic system is completed, generate a completion signal. The valve control function may be configured to set the valve in the closed state based on the completion signal, wherein the transceiver may be configured to transmit the completion signal. 
     According to a second aspect, a drainage or deaeration system for drainage or deaeration of a hydraulic system is provided. The drainage or deaeration system comprising a server and a valve assembly. The server is configured to transmit a control signal indicating a start of drainage or deaeration of the hydraulic system. The valve assembly comprising a valve, a valve assembly controller and a sensor. The valve comprising a first side and a second side. The first side is connected to the hydraulic system. The second side is connected to a mouth piece. The valve is configured to be set in an open state or in a closed state. Upon the valve is set in the open state fluid in the hydraulic system is free to pass the valve from the first side to the second side. The valve assembly controller comprising a transceiver and a valve control function. The transceiver is configured to receive the control signal. The valve assembly control circuit is configured to execute a valve control function and a drainage or deaeration function. The valve control function is configured to set the valve in the open state or closed state. The drainage or deaeration function is configured to, based on the control signal, instruct the valve control function to set the valve in the open state. The sensor is configured to monitor the mouth piece to obtain sensor data pertaining to a type of fluid leaving the mouth piece upon the valve is set in the open state, wherein the type of fluid is heat transfer fluid of the hydraulic system or air. The valve assembly controller may further be configured to transmit the sensor data to the server, and wherein the server comprises a server control circuit. The server control circuit may be configured to execute an analyze function. The analyze function may be configured to analyze the sensor data in order to determine whether a drainage or deaeration of the hydraulic system is complete. The analysis may be performed by running the sensor data through a neural network trained to determine whether the drainage or deaeration is completed. 
     The analyze function may further be configured to, upon the analyze function have concluded that the drainage or deaeration of the hydraulic system is completed, generate a completion signal. The server may be configured to transmit the completion signal to the valve assembly controller. The valve assembly controller may be configured to receive the completion signal. The valve control function may be configured to set the valve in the closed state based on the completion signal. 
     The valve assembly control circuit may further be configured to execute a sensor control function configured to set the sensor in a sleeping mode or a monitoring mode. The drainage or deaeration function may further be configured to, based on the control signal, instruct the sensor control function to set the sensor in the monitoring mode. The sensor control function may be configured to set the sensor in the sleeping mode based on the completion signal. 
     The above-mentioned features of the valve assembly according to the first aspect, when applicable, apply to the drainage or deaeration system of the second aspect as well. In order to avoid undue repetition, reference is made to the above. 
     According to a third aspect, a method for drainage or deaeration of a hydraulic system is provided. The method comprising setting a valve in an open state. The valve may be set in the open state based on a control signal indicating a start of drainage or deaeration of the hydraulic system. Upon the valve is set in the open state, fluid in the hydraulic system is free to pass the valve from a first side of the valve to a second side of the valve. The first side is connected to the hydraulic system and the second side is connected to a mouth piece. The method further comprising monitoring the mouth piece. The mouth piece is monitored by means of a sensor in order to obtain sensor data pertaining to a type of fluid leaving the mouth piece upon the valve is set in the open state, wherein the type of fluid is heat transfer fluid of the hydraulic system or air. 
     The method may further comprise determining, by analyzing the sensor data, whether the drainage or deaeration of the hydraulic system may be completed. Upon drainage or deaeration may be determined to be completed, the valve may be set in a closed state and a completion signal may be transmitted. 
     The above-mentioned features of the valve assembly according to the first aspect and/or the above-mentioned features of the drainage or deaeration system of the second aspect, when applicable, apply to the method of the third aspect as well. In order to avoid undue repetition, reference is made to the above. 
     A further scope of applicability of the present invention will become apparent from the detailed description given below. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the scope of the invention will become apparent to those skilled in the art from this detailed description. 
     Hence, it is to be understood that this invention is not limited to the particular component parts of the device described or acts of the methods described as such device and method may vary. It is also to be understood that the terminology used herein is for purpose of describing particular embodiments only and is not intended to be limiting. It must be noted that, as used in the specification and the appended claim, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements unless the context clearly dictates otherwise. Thus, for example, reference to “a unit” or “the unit” may include several devices, and the like. Furthermore, the words “comprising”, “including”, “containing” and similar wordings does not exclude other elements or steps. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiments of the invention. The figures are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout. 
         FIG.  1    is a schematic diagram of a valve assembly for drainage or deaeration of a hydraulic system. 
         FIG.  2    is a schematic diagram of a valve assembly controller. 
         FIG.  3    is a schematic diagram of a drainage or deaeration system for drainage or deaeration of a hydraulic system. 
         FIG.  4    is a schematic diagram of a server. 
         FIG.  5    is a flow chart illustrating a method for drainage or deaeration of a hydraulic system. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and to fully convey the scope of the invention to the skilled person. 
     In connection with  FIG.  1    a valve assembly  100  will be discussed. The valve assembly  100  is configured to drainage or deaeration of a hydraulic system  114 . The valve assembly  100  is configured to be connected to the hydraulic system  114 . The hydraulic system  114  may be any hydraulic system known in the art. As non-limiting examples, the hydraulic system  114  may be a radiator circuit, a district heating system, a district cooling system or a combined district heating and cooling system. The hydraulic system  114  may be arranged to transfer energy from one part of the hydraulic system  114  to another by transporting heat transfer fluid within the hydraulic system  114 . The heat transfer fluid may be pressurized. Preferably, the heat transfer fluid is a heat transfer liquid. The hydraulic system  114  may be equipped with a plurality of low points and high points. A low point may be located in the lowest portions of the hydraulic system  114 . A low point may be arranged in such way that heat transfer fluid in the hydraulic system  114  may be accumulated in the low point. A valve assembly  100  may be configured to drainage at a low point. A high point may be located in the highest portions of the hydraulic system  114 . A high point may be arranged in such way that air may be accumulated in the high point. A valve assembly  100  may be configured to deaeration at a high point. The drainage or deaeration of the hydraulic system  114  will be discussed in more detail further below. 
     The valve assembly  100  comprises a valve  102  and a mouth piece  108 . The valve  102  comprises a first side  104 . The first side  104  is configured to be connected to the hydraulic system  114 . Thus, the valve assembly  100  and the hydraulic system  114  may be connected by the first side  104  of the valve  102 . The valve  102  further comprise a second side  106 . The second side  106  is configured to be connected to the mouth piece  108 . Thus, the valve  102  may be arranged between the hydraulic system  114  and the mouth piece  108 . The valve  102  may be set to be in an open state. Upon the valve  102  may be in the open state, the valve  102  may be configured to allow fluid flowing from the hydraulic system  114  to the mouth piece  108 , via the valve  102 . Thus, upon the valve  102  is in the open state, the valve  102  may allow fluid to leave the hydraulic system  114  through the mouth piece  108 . The valve  102  may be in the open state during drainage or deaeration of the hydraulic system  114 . The valve  102  may be set to be in a closed state. Upon the valve  102  is in the closed state, fluid flowing from the hydraulic system  114  is hindered to pass the valve  102 . Thus, upon the valve  102  may be in the closed state, the valve  102  may hinder the fluid to leave the hydraulic system  114 . Thus, the valve  102  may be configured to control fluid that may be leaving the hydraulic system  114  through the mouth piece  108  via the valve  102 . The valve  102  may not be able to be in the open state and the closed state at the same time. Alternatively, or in combination, the valve  102  may be configured to be set in any other state than the open state or the closed state, for example in a partly open state. However, the valve  102  may only be configured to be set in one state at the time. Hence, the valve  102  may be set in different degrees of openness. The more open the valve  102  is set to be the more fluid may flow via the valve  102 . The open state may have different open modes. 
     The valve assembly  100  comprises a sensor  112 . The sensor  112  may be configured to communicate with a valve assembly controller  110  of the valve assembly  100 . The sensor  112  may be configured to monitor the mouth piece  108 . The sensor  112  may be configured to obtain sensor data, wherein the sensor data may be pertaining to a type of fluid that is leaving the mouth piece  108 . The type of fluid may be heat transfer fluid of the hydraulic system. The type of fluid may be air. The sensor data may comprise data relating to the fluid that is leaving the mouth piece  108 . According to one non-limiting example, the data may be related to what type of fluid that is leaving the mouth piece  108  and if the type of fluid that is leaving the mouth piece  108  may change during the drainage or deaeration. According to yet one non-limiting example, the data may be related to similar data that an operator&#39;s senses may be able to obtain. The sensor  112  may be configured to monitor the type of fluid such that the sensor  112  may obtain data when the fluid transit from one phase to another, e.g. when the fluid transit from the heat transfer fluid of the hydraulic system to air or vice versa. The sensor  112  may be configured to be in a monitoring mode or in a sleeping mode. Upon the sensor  112  is in the monitoring mode, the sensor  112  monitors the mouth piece  108  and thus, obtain sensor data. Upon the sensor  112  is in the sleeping mode, the sensor  112  is not able to obtain the sensor data. The sensor  112  may not be able to be in the monitoring mode and the sleeping mode at the same time. As a non-limiting example, the sensor  112  may be in the monitoring mode when the valve  102  is in the open state. As yet non-limiting example, the sensor  112  may be in the sleeping mode when the valve  102  is in the closed state. Upon the valve  102  is in the closed state, the fluid is hindered from leaving the mouth piece  108  and thus, there is no sensor data pertaining to the fluid leaving the mouth piece  108  to obtain. The sensor  112  may comprise a camera. The camera may be configured to capture images of the mouth piece  108 . The images may be in the form of a video stream. The camera may be an IR-camera, a camera configured to capture visible light, or a camera configured to capture both visible light and IR. The sensor  112  may further comprise an illuminator, wherein the illuminator is configured to illuminate the mouth piece  108 . The illuminator may be an IR-illuminator, an illuminator emitting visible light, or an illuminator configured to emit both visible light and IR. Alternatively, or in combination, the sensor  112  may comprise a microphone. Alternatively, or in combination, the sensor  112  may comprise a tactile sensor. The tactile sensor may be configured to detect whether the fluid is present in the mouth piece  108 . If the fluid is present in the mouth piece  108 , it should be understood that the fluid is leaving the mouth piece  108 . Alternatively, or in combination, the sensor  112  may comprise an electric sensor. Alternatively, or in combination, the sensor  112  may comprise a magnetic sensor. The electric sensor may be configured to detect whether it is fluid or air that is leaving the mouth piece  108 . The magnetic sensor may be configured to detect whether it is fluid or air that is leaving the mouth piece  108 . Alternatively, or in combination, the sensor  112  may comprise a detection means. The detection means may be configured to detect a trace element. As a non-limiting example, the trace element may be Pyranine. The trace element may be blended in the fluid. The trace element may be added in the hydraulic system  114 . If the detection means detect the trace element, it should be understood that the fluid is leaving the mouth piece  108  and hence, the detection means may obtain sensor data. The trace element may be any trace element that may be added to the hydraulic system  114 . Alternatively, or in combination, the trace element may be any trace element that may be added to the fluid. Thus, the detection means may be configured to detect any trace element present in the hydraulic system  114 . Alternatively, or in combination, the detection means may be configured to detect any trace element present in the fluid. 
     Although discussed separately, any combination of the sensors and/or detection means may be used to achieve the purpose of obtaining sensor data. Thus, the sensor  112  may be any sensor configured to detect and/or measure and/or determine presence of fluid and/or air in the mouth piece  108 . The sensor  112  may comprise more than one sensor feature. The sensor  112  may be configured to obtain sensor data from one sensor or detection means. The sensor  112  may be configured to obtain sensor data from more than one sensor and/or detection means. Thus, there may be a combination of sensors within the valve assembly  100 . 
     The valve assembly controller  110  is configured to control the valve assembly  100 . The valve assembly controller  110  may be configured to control the valve  102  and the sensor  112 . The valve assembly controller  110  will be discussed in more detail in connection with  FIG.  2   . 
     One or more valve assemblies  100  may be connected to a specific hydraulic system  114 . According to one example, the hydraulic system  114  may be connected to as many valve assemblies  100  as there is low points and/or high points in the hydraulic system  114 . Thus, the number of valve assemblies  100  may depend on the number of low points and/or high points. By this arrangement, there may be one valve assembly controller  110  configured to control one valve assembly  100 . Thus, by this arrangement, there might be the same numbers of valves  102 , mouth pieces  108 , valve assembly controllers  110  and sensors  112  as the number of low points and/or high points. Alternatively, or in combination, there might be one valve assembly controller  110  configured to control more than one valve assembly  100 . 
     Thus, the present disclosure is not limited to the illustration in  FIG.  1   , but there can be any number of valve assemblies  100  connected to the hydraulic system  114  in order to provide for an efficient and flexible drainage or deaeration of the hydraulic system  114 . 
     In connection with  FIG.  2    the valve assembly controller  110  configured to control the valve assembly  100  will be discussed in more detail. The valve assembly controller  110  comprises a transceiver  202 , a valve assembly control circuit  204  and a memory  208 . 
     The transceiver  202  is configured to communicate with the valve  102 . The transceiver  202  is configured to communicate with the sensor  118 . The transceiver  202  is configured to communicate with any device suitable to receive or transmit a signal from/to the transceiver  202 . The communication path over which the communication is made may be wired or wireless. The communication may include data transfers, and the like. Data transfers may include, but are not limited to, downloading and/or uploading data and receiving or sending messages. The data may be processed by the valve assembly controller  110 . The processing may include storing the data in a memory, e.g. the memory  208  of the valve assembly controller  110 , executing operations or functions, and so forth. The transceiver  202  may be configured to receive a control signal. The control signal may indicate a start of the drainage or deaeration of the hydraulic system  114 . The control signal may be transmitted from a drainage or deaeration operating server. 
     The valve assembly control circuit  204  is configured to carry out overall control of functions and operations of the valve assembly controller  110 . The valve assembly control circuit  204  may include a processor  206 , such as a central processing unit (CPU), microcontroller, or microprocessor. The processor  206  is configured to execute program code stored in the memory  208 , in order to carry out functions and operations of the valve assembly controller  110 . 
     The memory may be one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, a random access memory (RAM), or other suitable devices. In a typical arrangement, the memory  208  may include a non-volatile memory for long term data storage and a volatile memory that functions as system memory for the valve assembly control circuit  204 . The memory  208  may exchange data with the valve assembly control circuit  204  over a data bus. Accompanying control lines and an address bus between the memory  208  and the valve assembly control circuit  204  also may be present. 
     Functions and operations of the valve assembly controller  110  may be embodied in the form of executable logic routines (e.g. lines of code, software programs, etc.) that are stored on a non-transitory computer readable medium (e.g. the memory  208 ) of the valve assembly controller  110  and are executed by the valve assembly control circuit  204  (e.g. the processor  206 ). Furthermore, the functions and operations of the valve assembly controller  110  may be a stand-alone software application of form a part of a software application that carries out additional tasks related to the valve assembly controller  110 . The described functions and operations may be considering a method that the corresponding device is configured to carry out. Also, while the described functions and operations may be implemented in software, such functionality may as well be carried out via dedicated hardware or firmware, or some combination of hardware, firmware and/or software. 
     The valve assembly control circuit  204  may be configured to execute a valve control function  210 . The valve control function  210  may be configured to set the valve  102  in the open state. The valve control function  210  may be configured to set the valve  102  in the closed state. 
     The valve assembly control circuit  204  may be configured to execute a drainage or deaeration function  212 . The drainage or deaeration function  212  is configured to, based on the control signal, instruct the valve control function  210  to set the valve  102  in the open state. Thus, upon the valve assembly controller  110  receive the control signal, the drainage or deaeration function  212  may instruct the valve control function  210  to set the valve  102  in the open state such as the drainage or deaeration may start. 
     The valve assembly control circuit  204  may be configured to execute a sensor control function  214 . The sensor control function  214  may be configured to set the sensor  112  in the monitoring mode. The sensor control function  214  may be configured to set the sensor  112  in the sleeping mode. 
     The drainage or deaeration function  212  may further be configured to, based on the control signal, instruct the sensor control function  214  to set the sensor  112  in the monitoring mode. Thus, upon the valve assembly controller  110  receive the control signal, the drainage or deaeration function  212  may instruct the sensor control function  214  to set the sensor  112  in the monitoring mode such as the sensor  112  may be able to obtain sensor data. The sensor data may be analyzed locally at the valve assembly controller  110 , see the discussion on the analyze function  216  below. Alternatively, or in combination, the sensor data may be analyzed remotely at a server  302 , see discussion in connection with  FIGS.  3  and  4   . Yet alternatively, or in combination, the sensor data may be analyzed by an operator controlling the drainage or deaeration of the hydraulic system  114 . Upon the analyzing determine that the drainage or deaeration is completed, a completion signal may be transmitted to the valve assembly controller  110 . The completion signal may comprise information indicating the completed drainage or deaeration of the hydraulic system  114 . By drainage or deaeration being completed, it is meant that the drainage or deaeration has been successfully performed. Thus, the low points and/or high points in the hydraulic system  114  have been fully drainage or deaeration. That the drainage is completed may be determined by that the sensor  112  detects that air is leaving the mouth piece  108  instead of fluid. Thus, when starting the drainage, fluid is leaving the mouth piece  108 . When air is leaving the mouth piece  108  instead, it may be determined that the drainage is completed. That the deaeration is completed may be determined by that the sensor  112  detects that fluid is leaving the mouth piece  108  instead of air. Thus, when starting the deaeration, air is leaving the mouth piece  108 . When fluid is leaving the mouth piece  108  instead, it may be determined that the deaeration is completed. 
     Hence, the valve assembly control circuit  204  may be configured to execute an analyze function  216 . The analyze function  216  is configured to analyze the sensor data obtained by the sensor  112 . The analyze function  216  may be configured to analyze the sensor data obtained by the sensor  112  in order to determine whether the drainage or deaeration of the hydraulic system  114  is completed. The analyze function  216  may be configured to analyze the sensor data by determine what type of fluid the sensor data pertain to. The type of fluid may be the heat transfer fluid of the hydraulic system or air. Thus, the analyze function  216  may be configured to analyze whether it is the heat transfer fluid of the hydraulic system or air that is leaving the mouth piece  108 . The analysis may be performed by running the sensor data through a neural network. The neural network may be trained to determine whether the drainage or deaeration is completed or not. The neural network may be trained to detect a transition between the fluid and air, or the other way around, in the mouth piece  108 . Thus, the neural network may be trained to detect the transition based on the sensor data. The neural network may be trained by one or more test sequences. In the test sequences, the time period for drainage or deaeration is pre-defined and the neural network may be trained to detect the pre-defined time period. Thus, if the neural network is trained to detect the pre-defined time period, the neural network may also be trained to determine when the drainage or deaeration may be completed. Thereinafter, parameters indicating that the drainage or deaeration is completed by the neural network may be transmitted to the analyze function  216 . The analyze function  216  is further configured to, upon the analyze function  216  and/or the neural network has concluded that the drainage or deaeration of the hydraulic system  114  is completed, generate the completion signal. Thus, by analyzing the sensor data, the valve assembly controller  110  may be configured to determine whether the drainage or deaeration is completed. 
     The valve control function  210  may further be configured to, based on the completion signal, set the valve  102  in the closed state. The sensor control function  214  may further be configured to, based on the completion signal, set the sensor  112  in the sleeping mode. 
     Hence, the valve assembly controller  110  may receive the control signal indicating that a drainage or deaeration is to may start. Based on the control signal, the valve control function  210  may be instructed to set the valve  102  in the open state and the sensor control function  214  may be instructed to set the sensor  112  in the monitoring mode. Upon the sensor  112  is in the monitoring mode it obtains sensor data. The sensor data pertains to fluid emitted at the mouthpiece  108 . During the drainage or deaeration, the sensor  112  may transmit the obtained sensor data to the valve assembly controller  110 . The sensor data may be analyzed locally at the valve assembly controller  110  by the analyze function  216 . Alternatively, or in combination the sensor data may be analyzed remotely at the server  302  discussed in connection with  FIG.  4   . Yet alternatively, or in combination, an operator may analyze the sensor data. The sensor data may be images and/or sound depicting fluid leaving the mouth piece  108 . Upon the analyzing indicates that the drainage or deaeration is complete, the operator and/or the analyze function  216 ,  404  may transmit a completion signal. Based on the completion signal, the valve control function  210  may be configured to set the valve  102  in the closed state and the sensor control function  214  may be configured to set the sensor  112  in the sleeping mode. Hence, the drainage or deaeration is completed and the hydraulic system  114  may be set in normal operation. 
     In connection with  FIG.  3    a drainage or deaeration system  200  will be discussed. The drainage or deaeration system  200  is configured to drainage or deaeration of the hydraulic system  114 . The drainage or deaeration system  200  comprises a valve assembly  100  as discussed in connection with  FIG.  1   , and a server  302 . In order to avoid undue repetition, references for the valve assembly  100  and the hydraulic system  114  are made to the above. The server  302  will be discussed in more detail in connection with  FIG.  4   . 
     The server  302  comprises a transceiver  401 , a server control circuit  402  and a memory  408 . The transceiver  401  and the memory  408  are arranged in the same way as the transceiver  202  and memory  208  discussed in connection with the valve assembly controller  110  illustrated in  FIG.  2   . In order to avoid undue repetition, reference is made to the above. 
     The sever control circuit  402  is configured to carry out overall control of functions and operations of the server  302 . The server control circuit  402  may include a processor  406 , such as a central processing unit (CPU), microcontroller, or microprocessor. The processor  406  is configured to execute program code stored in the memory  408 , in order to carry out functions and operations of the server  302 . 
     Functions and operations of the server  302  may be embodied in the form of executable logic routines (e.g. lines of code, software programs, etc.) that are stored on a non-transitory computer readable medium (e.g. the memory  408 ) of the server and are executed by the server control circuit  402  (e.g. the processor  406 ). Furthermore, the functions and operations of the server  302  may be a stand-alone software application of form a part of a software application that carries out additional tasks related to the server  302 . The described functions and operations may be considering a method that the corresponding device is configured to carry out. Also, while the described functions and operations may be implemented in software, such functionality may as well be carried out via dedicated hardware or firmware, or some combination of hardware, firmware and/or software. 
     The server  302  may be configured to transmit the control signal indicating a start of a drainage or deaeration of the hydraulic system  11 . 
     The server  302  may be configured to receive the sensor data from the valve assembly controller  110 . The server control circuit  402  may be configured to execute a second analyze function  404 . The second analyze function  404  is configured to analyze the sensor data in order to determine whether the drainage or deaeration of the hydraulic system  114  is completed. The analysis may be performed by running the sensor data through the neural network. The neural network may be trained to determine whether the drainage or deaeration is completed. The second analyze function  404  is further configured to generate the completion signal. The server  302  may be configured to transmit the completion signal to the valve assembly controller  110 . Thus, the second analyze function  404  is performed in a similar way as the analyze function  216 . Upon the valve assembly  100  may be connected to the server  302 , the analysis of the sensor data may be performed in the server  302  instead of in the valve assembly controller  110 . Alternatively, or in combination, the analyzing may be performed in both the server  302  and in the valve assembly controller  110 . 
     In addition to the above, the server  302  and the valve assembly controller  110  may communicate and thus, together perform the same functions as discussed in connection with  FIG.  2   . The server  302  may be configured to communicate with one valve assembly  100 . The server  302  may be configured to communicate with more than one valve assembly  110 . 
     In connection with  FIG.  5    a flow chart illustrating a method for drainage or deaeration of the hydraulic system  114  will be discussed. The method comprises the following steps. The steps may be performed in any suitable order. 
     Setting S 502  the valve  102  in an open state. The step is based on the control signal, wherein the control signal may be indicating a start of drainage or deaeration of the hydraulic system  114 . As being discussed above, upon the valve  102  is set in the open state, fluid in the hydraulic system  114  may be free to pass the valve  102  from the first side  104  to the second side  106 . The first side  104  may be configured to be connected to the hydraulic system  114 . The second side  106  may be connected to the mouth piece  108 . 
     Monitoring S 504 , by means of the sensor  112 , the mouth piece  108 . Thus, by monitoring S 504  the mouth piece  108 , sensor data pertaining to fluid that is leaving the mouth piece may be obtained. The sensor data may be obtained upon the valve  102  is set in the open state. 
     The method may further comprise one or more of the following steps. Determining S 506 , by analyzing the sensor data, whether the drainage or deaeration of the hydraulic system  114  is completed. Upon the drainage or deaeration of the hydraulic system  114  is completed, setting S 508  the valve  102  in the closed state and transmitting the completion signal. 
     The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. 
     For example, the valve assembly  100  may comprise a battery powering one or more of the components of the valve assembly  100 . The battery may be exchangeable. Alternatively, or in combination, the battery may be chargeable. 
     The sensor  112  may comprise one or more of: a temperature sensor, a pressure sensor and a humidity sensor. 
     The sensor may comprise a LIDAR. A LIDAR may give information about proximity alerts and measure speed of fluid ejected from the mouth piece  108 . 
     Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.