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Title:
SYSTEM AND METHOD FOR RECOVERING A REFRIGERANT CONTAINED IN A VEHICLE AIR CONDITIONING SYSTEM
Document Type and Number:
WIPO Patent Application WO/2019/142133
Kind Code:
A1
Abstract:
A method for recovering a refrigerant (FA) contained in a vehicle (4) air conditioning system (3). The method comprised arranging a refrigerant recovery tank (2) that comprises a pair of closed containers (6) (8), which are arranged one inside the other; hydraulically connecting a first container to the air conditioning system (3); transferring at least part of a first refrigerant (FA) contained in the conditioning system (3) to the first container; supplying a second refrigerant (FB) to a second container; and cooling the second refrigerant (FB) so as to reduce the temperature of the first refrigerant (FA) contained in the first container in order to cause a pressure reduction in the first container, which generates, in turn, a transfer of the first refrigerant (FA) from the air conditioning system to the first container.

Inventors:
VIANELLO, Bruno (Via San Rocco 58, Roncade, 31056, IT)
MENEGHEL, Stefano (Via 1 Maggio 9, Monastier Di Treviso, 31050, IT)
Application Number:
IB2019/050397
Publication Date:
July 25, 2019
Filing Date:
January 17, 2019
Export Citation:
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Assignee:
TEXA S.P.A. (Via 1 Maggio 9, Monastier Di Treviso, 31050, IT)
International Classes:
F25B45/00
Foreign References:
US5101637A1992-04-07
US5150577A1992-09-29
US5582014A1996-12-10
US5339646A1994-08-23
Attorney, Agent or Firm:
ZAMPROGNO, Bruno et al. (Studio Torta S.p.A, Via Viotti 9, Torino, 10121, IT)
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Claims:
CLAIMS

1. A method for recovering a first refrigerant (FA) contained in an air conditioning system (3) of a vehicle (4) ;

the method comprising the steps of:

a) arranging a refrigerant recovery tank (2) that comprises a pair of closed containers (6) (8), which are arranged one inside the other;

c) hydraulically connecting a first container of said pair of containers (6) (8) to said air conditioning system (3) ;

e) supplying a second refrigerant (FB) to a second container of said pair of containers (6) (8);

g) cooling the second refrigerant (FB) in said second container for absorbing heat from the first refrigerant (FA) contained in said first container so as to cause a pressure reduction of the first refrigerant (FA) in said first container until reaching a first pre-set pressure (PA3(t));

i) said first pre-set pressure (PA3(t)) of the first refrigerant (FA) in said first container being lower than the pressure (PA1 (t) ) of the refrigerant (FA) contained in said air conditioning system (3) and causing the transfer of the refrigerant (FA) from the air conditioning system (3) to said first container.

2. The method according to claim 1, wherein said step g) of cooling the second refrigerant (FB) comprises the step of carrying out a suction in said second container so as to reduce the pressure (PB2 (t) ) of the second refrigerant (FB) contained in said second container itself, until reaching a second pre-set pressure (PB3(t)).

3. The method according to claim 1 or 2, wherein said step g) is preceded by the step f) of reducing the pressure in said first container to a pressure (Po) lower than the pressure (PA1 (t) ) of the first refrigerant (FA) contained in said air conditioning system (3) in order to cause the transfer of at least part of said first refrigerant (FA) from said air conditioning system (3) to said first container .

4. The method according to any one of the foregoing claims, wherein:

said second container comprises an inner chamber which houses the first container and has an internal volume greater than the external volume of said first container;

said step g) comprises the step of supplying the second refrigerant (FB) to the internal chamber of the second container so as to immerse the first container in the second refrigerant (FB) .

5. The method according to any one of the preceding claims, comprising the steps of:

arranging a maintenance apparatus of an air conditioning system (200) provided with:

a charging circuit (12) configured to provide said second refrigerant (FB) ;

a suction circuit (10) designed to carry out a suction in said second container;

an external hydraulic connector (15) selectively connectable to said charging circuit (12) and/or to said suction circuit (10);

and wherein:

the step e) comprises:

- hydraulically connecting the second container to said hydraulic connector (15) via an external duct (16);

- activating the refrigerant charging circuit (12) for providing the second refrigerant (FB) to the second container via the hydraulic connector (15) and said external duct (16) ;

said step g) comprises:

- activating the suction circuit (10) for reducing the pressure (PB2 (t) ) of the second refrigerant (FB) in said second container until reaching a pre-set pressure (PB3(t)) .

6. The method according to the claims 3 and 5, wherein said step f) comprises:

- connecting the first container to the external hydraulic connector (15) via said external duct (16);

- controlling the suction circuit (10) for reducing the pressure in said first container to a pre-set pressure (Po) .

7. A system (1) for recovering a refrigerant (FA) contained in a vehicle (4) air conditioning system (3);

the system comprises:

a refrigerant recovery tank (2) that comprises a pair of closed containers (6) (8), which are arranged one inside the other;

an external hydraulic duct (18) which hydraulically connects a first container of said pair of containers (6) (8) to said air conditioning system (3);

refrigerant charging circuit (12) configured to provide a second refrigerant (FB) ;

a hydraulic duct (16) for hydraulically connecting the refrigerant charging circuit (12) to a second container of said pair of closed containers (6) (8);

cooling means (10) (13);

an electronic control device (100) configured in order to :

control the refrigerant charging circuit (12) in order to supply said second refrigerant (FB) to said second container;

control said cooling means (10) (13) for cooling the second refrigerant (FB) in said second container thus absorbing heat from the first refrigerant (FA) contained in said first container so as to cause a pressure reduction of the first refrigerant (FA) in said first container until reaching a first pre-set pressure (PA3(t));

said first pre-set pressure (PA3(t)) of the first refrigerant (FA) in said first container being lower than the pressure (PA1 (t) ) of the refrigerant (FA) contained in said air conditioning system (3) and causing the transfer of the refrigerant (FA) from the air conditioning system (3) to said first container.

8. The system according to claim 7 wherein said cooling means comprise a suction circuit (10) connected to said second container:

said electronic control device (100) being configured to control said suction circuit (10) so as to carry out a suction in said second container for reducing the pressure of the second refrigerant (FB) contained in said second container itself until reaching a second pre-set pressure (PA3(t)) and causing a temperature reduction of the second refrigerant (FB) itself.

9. The system according to claim 8, wherein said suction circuit (10), said refrigerant charging circuit (12), and said electronic control device (100) are included in a maintenance apparatus of an air conditioning system (200) .

10. The system according to claim 9, wherein said maintenance apparatus of an air conditioning system (200) has a first external connector (15) designed to be selectively connected to the suction circuit (10) and/or to said refrigerant charging circuit (12), said air conditioning system (3) has at least a second external terminal (19) through which said first refrigerant (FA) is designed to flow; said system also comprises a recovery apparatus (201) that is structured for supporting said refrigerant recovery tank (2) and comprises a series of hydraulic connectors (203) (204) (206) which are connected to said first and second containers of said refrigerant recovery tank (2) and are designed to be connected to said first and second external terminals and to an additional refrigerant (FA) recovery and disposal tank (20) .

11. A refrigerant recovery tank (2) for recovering a refrigerant contained in a vehicle (4) air conditioning system (3) ;

said refrigerant recovery tank (2) comprising a pair of closed containers, which are arranged one inside the other; the refrigerant recovery tank (2) having at least two external hydraulic connectors one of which, is in fluidic communication with the internal chamber of the external container while the other hydraulic connector is in fluidic communication with the internal chamber of the internal container via an internal duct which at least partially passes through the internal chamber of the external container .

Description:
SYSTEM AND METHOD FOR RECOVERING A REFRIGERANT CONTAINED IN

A VEHICLE AIR CONDITIONING SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority from Italian patent application no. 102018000001154 filed on 17/01/2018, the entire disclosure of which is incorporated herein by reference .

TECHNICAL FIELD

The invention relates to the recovery of a refrigerant contained in an air conditioning system of a motor vehicle.

BACKGROUND ART

When, during a motor vehicle air conditioning system maintenance operation, the refrigerant present in it is "non- compliant", namely it is not pure because it was contaminated by other gases and/or is not in accordance with the law, the air conditioning system of the motor vehicle needs to be completely emptied from the refrigerant. The recovered refrigerant must then be stored in a proper tank suited for the disposal thereof.

DISCLOSURE OF INVENTION

The object of the invention is to provide a simple and economic system, which is capable of storing, in a refrigerant recovery tank, the refrigerant present in an air conditioning system of a vehicle during the emptying thereof. According to the invention, there are provided a method and a system for recovering a refrigerant contained in an air conditioning system of a motor vehicle as set forth in the appended claims .

According to the invention, there is further provided a refrigerant recovery tank as claimed in the appended claims .

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the accompanying drawings, which show a non-limiting embodiment thereof, wherein:

- Figure 1 shows a block diagram of a refrigerant recovery system according to the invention;

- Figures 2 to 7 schematically show the operating steps implemented by the refrigerant recovery method according to the invention;

- Figure 8 shows a refrigerant recovery tank, with sectional parts and parts removed for greater clarity, according to the invention; whereas

- Figure 9 shows a convenient embodiment of the refrigerant recovery system according to Figure 1.

BEST MODE FOR CARRYING OUT THE INVENTION

With reference to Figure 1, number 1 indicates, as a whole, a refrigerant recovery system, which is provided with a refrigerant recovery tank 2, which is designed to be hydraulically connected to an air conditioning system 3 mounted no board a motor vehicle 4. The system 1 is configured so as to transfer a refrigerant FA (referred to as first refrigerant in the claims) contained in the air conditioning system 3 into the refrigerant recovery tank 2.

For the purposes of the invention, the term "motor vehicle" indicates any motor vehicle provided with four wheels, such as a car, a truck, a bus or the like. Furthermore, for the purposes of the invention, the term "air conditioning system" indicates a system which is capable of conditioning the air in the passenger compartment of the motor vehicle 4.

With reference to the preferred embodiment shown in Figures 1 and 8, the refrigerant recovery tank 2 comprises two containers arranged inside one another. With reference to the preferred explanatory embodiment shown in Figure 8, the two containers 6 and 8 are closed and are made of a rigid material, preferably a metal material.

With reference to the preferred explanatory embodiment shown in Figure 8, the refrigerant recovery tank 2 can have at least two outer hydraulic terminals or connectors, one of them, indicated with 5, being in hydraulic communication with the inner chamber of the outer container 6, whereas the other hydraulic connector, indicated with 7, is in direct hydraulic communication with the inner chamber of the inner container 8, preferably through an inner duct 9, which can extend so as to at least partially go through, preferably at the centre, the inner chamber of the outer container 6.

With reference to the preferred embodiment shown in the accompanying Figures, the two containers 6 and 8 can each have an approximately cylindrical or ovoid shape or any other similar shape. The inner chamber of the outer container 6 is sized so as to have an inner volume which is greater than the outer volume of the inner container 8. The inner container 8 can preferably be arranged in the inner chamber of the outer container 6 so as to be spaced apart from the inner surface of the outer container 6, which delimits the inner chamber thereof, so that it is not in direct contact with the outer container 6. To this aim, there can be support and/or spacer elements (not shown herein) of the inner container 8, which are firmly connected to the outer container 6, for example to its inner surface, and are structured so as to keep the container 8 suspended in the inner chamber of the outer container 6, preferably in a central position.

With reference to the referred embodiment shown in Figure 1, the refrigerant recovery system 1 can further comprise: a suction circuit 10, which is designed to be selectively and/or alternatively connected to the two containers of the refrigerant recovery tank 2 and is designed to suck the refrigerant fluid contained in the container connected thereto in a given instant, so as to reduce the pressure inside the container (in the way described below) ; preferably a tank 11 containing a refrigerant FB (referred to as second refrigerant in the claims);

a refrigerant charging circuit 12, which is designed to be selectively and/or alternatively connected to the tank 11 and/or to the two containers of the refrigerant recovery tank 2 in order to supply/feed the refrigerant FB to the container connected thereto in a given instant; and

an electronic control device 100, which is configured so as to control at least the suction circuit 10 and the refrigerant charging circuit 12.

According to a preferred embodiment, the electronic control device 100 is configured so as to control the suction circuit 10 when the latter is hydraulically connected to a first container of the refrigerant recovery tank 2, so as to reduce the pressure in the first container to a pre-set pressure, which is smaller than the pressure of the refrigerant FA present in the air conditioning system 3.

According to a preferred embodiment, the electronic control circuit 100 is further configured so as to control the charging circuit 12 when the second container is connected to the charging circuit 12 and, preferably, the first container is connected to the air conditioning system 3, so as to supply the refrigerant FB to the second container .

The electronic control unit 100 is further configured so as to control the suction circuit 10 when the first container is connected to the air conditioning system 3 and the second container is connected to the suction circuit 10, so as to reduce the pressure of the second refrigerant FB contained in the second container until it reaches a pre-set pressure. The pressure reduction of the second refrigerant FB in the second container caused by a suction of the refrigerant fluid FB determines a temperature reduction thereof. During the temperature reduction, the refrigerant FB absorbs heat from the refrigerant FA contained in the first container, which, in turn, reduces its temperature and, as a consequence, its pressure.

The Applicant found out that the refrigerant FB can conveniently be cooled down in the second container in an indirect manner by reducing the pressure of the refrigerant FB contained in it. The cooling of the refrigerant FB in the second container causes a temperature reduction of the refrigerant FA in the first container and a change of state thereof from vapour to liquid. The state transition of the refrigerant FA in the first container determines a reduction of the pressure inside it until a pre-set pressure is reached which is smaller than the pressure of the refrigerant FA contained in the air conditioning system 3. The difference between the pressure of the refrigerant FA in the air conditioning system 3 and the reduced pre-set temperature inside the first container of the tank 2 conveniently causes the transfer of the refrigerant FA from the air conditioning system 3 to said first container of the refrigerant recovery tank 2 and, thus, determines the emptying of the refrigerant FA left in it.

The method for recovering the refrigerant FA from the air conditioning system 3 and for storing the refrigerant FA in the recovery tank 2 will now be described with reference to Figures 2 to 5. In the description below, in order to increase the clarity of the description itself, though without for this reason loosing in generality and/or limiting the invention, we will assume that: the refrigerant FA is stored in the inner container 8; the pressure and the temperature of the refrigerant FA (in the instant t) in the air conditioning system 3 are PA1 (t) and TA1 (t) , respectively; Po is a pre-set minimum temperature reached inside the container 8 by means of a suction step described hereinafter .

With reference to Figure 2, the recovery method can preferably comprise the step of hydraulically connecting the container 8 to the suction circuit 10. The refrigerant recovery system 1 can preferably be provided with an outer duct 16 and with at least one outer connector or terminal

15, which is hydraulically connected to the suction circuit 10. For this purpose, the system 1 can comprise a manifold circuit 14 provided with solenoid valves (not shown) , which can be controlled by the electronic control device 100 so as to selectively and/or alternatively connect the outer terminal 15 to the refrigerant charging circuit 12 and/or to the suction circuit 10.

The outer duct 16 is preferably connected to the connector 7 of the tank 2 and to the outer terminal 15.

The recovery method can require the electronic control device 100 to control the suction circuit 10 so as to reduce the pressure present inside the container 8 until it reaches the pre-set minimum pressure Po. The pre-set minimum pressure Po is set at a value that is smaller than the pressure PA1 (t) of the refrigerant present in the air conditioning system 2. For example, during this step, the suction circuit 10 could be controlled so as to create a pressure state inside the container 8 corresponding to a state of strong vacuum (depression) .

With reference to Figures 3 and 4, the recovery method can preferably comprise the step of hydraulically connecting the inner container 8 to the air conditioning system 3. The refrigerant recovery stem 1 can be provided with an outer duct 18 and this step can involve connecting the outer duct 18 to the connector 7 of the tank 2 and to a terminal 19 of the air conditioning system 3. During this step, the pressure difference between the pressure PA1 (t) of the refrigerant FA in the air conditioning system 2 and the pressure Po<<PAl (t) in the inner container 8 causes the transfer, to the latter, of at least a part/quantity of the refrigerant FA. The transfer of the refrigerant FA ends when a pressure balance condition is reached, in which, for example, the pressure PA2(t) of the refrigerant FA in the container 8 reaches the pressure PA1 (t) of the refrigerant FA in the air conditioning system 3, PA2 (t ) =PA1 (t ) .

In this condition, the container 8 contains a given quantity of the refrigerant FA partially in the liquid state and a given quantity of the refrigerant FA partially in the vapour state and has the pressure PA2 (t) and the temperature TA2 (t) .

With reference to Figures 4 and 5, the method comprises the step of supplying the refrigerant FB to the outer container 6. The method can preferably require the electronic control device 100 to operate the refrigerant charging circuit 12 so as to supply a given quantity of refrigerant FB to the inner chamber of the outer container 6, through the outer duct 16. The supplied quantity of refrigerant can be established based on the volume of the two containers 6 and 8, so as to partially or completely drown the outer surface of the inner container 8. The Applicant found out that, by completely drowning the outer surface of the inner container 8, there conveniently is a greater absorption of heat from the refrigerant FA during the cooling thereof. At the end of the supply of the refrigerant fluid FB, the pressure of the refrigerant fluid FB in the inner chamber of the outer container 6 can be PB2 (t) and its temperature in the balance condition can be TB2 (t) .

The method further comprises the step of cooling the refrigerant FB in the outer container 6 so as to absorb heat from the refrigerant FA contained in the container 8 in order to cause a pressure reduction of the refrigerant FA in the first container 8 until a first pre-set pressure PA3(t) is reached. The first pre-set pressure PA3(t) of the refrigerant FA in the container 8 is smaller than the pressure PA1 (t) of the refrigerant FA contained in the air conditioning system 3, thus conveniently causing the transfer of the refrigerant FA from the air conditioning system 3 to the container 8.

According to a preferred embodiment shown in Figure 6, the method can require the electronic control device 100 to control the suction circuit 10 so as to reduce the pressure of the refrigerant FB in the inner chamber of the outer container 6 from an initial value PB2 (t) to a pre-set pressure PB3(t), which is smaller than the pressure PB2 (t) .

Obviously, in this step, the reduction of the pressure in the closed container 6 (constant volume) caused by the suction of the refrigerant FB determines a change in its balance state, thus causing a controlled temperature reduction from TB2 (t) to a smaller temperature TB3(t), (TB3 (t ) <TB2 (t ) ) of the refrigerant FB, which, as a consequence, cools down.

With reference to Figure 6, in this step, the refrigerant FA releases heat to the refrigerant FB and, hence, reduces its temperature to a smaller temperature TA3 (t ) <TA2 (t ) . The release of heat determines an at least partial change of state of the refrigerant FA contained in the container 8, a part/quantity of which at least partially shifts from the vapour state to the liquid state. The vapour to liquid state transition determines then a reduction of the pressure of the refrigerant FA present in the inner container 8, until it reaches a pressure value PA3(t) which is smaller than the pressure PA1 (t) of the refrigerant FA present in the air conditioning system 3.

The pressure difference between PA3(t) and PA1 (t) determines a transfer, through the duct 18, of the refrigerant FA from the air conditioning system 3 to the container 8.

Obviously, the vapour to liquid state transition of part of the refrigerant FA determines an absorption of heat from the latter, which lowers the balance pressure thereof and hence, causes an additional transfer of refrigerant FA from the air conditioning system 3 to the inner container 8. The transfer of the refrigerant FA ends when the pressure PA3(t) of the refrigerant FA in the container 8 and the pressure PAl(t) of the refrigerant FA in the air conditioning system 3 are the same.

The system 1 can conveniently continue reducing, in an indirect manner, the temperature TA3(t), carrying out a reduction of the pressure of the refrigerant, so as to determine a corresponding controlled reduction of the pressure PA3(t) of the refrigerant FA present in the inner container 8 until a complete emptying condition of the air conditioning system 3 is reached.

Furthermore, the method can conveniently and preferably comprise, at the end of the emptying, the step of recovering the refrigerant and storing it, for example, in the tank 11. This step can require the electronic control device 100 to operate the suction circuit 10 so as to suck, through the duct 16, the refrigerant FB from the container 6 and store the sucked refrigerant FB in the tank 11.

With reference to Figure 7, the method can further conveniently comprise the step of hydraulically connecting the container 8 of the recovery tank 2 to another additional tank 20 suited for disposal. The transfer of the refrigerant

FA from the recovery tank 2 to the tank 20 can be carried out in different ways, for example through a pumping device (not shown) or by generating a strong vacuum state (depression) in the inner containing chamber of the tank 20.

Obviously, according to a variant which is not shown herein, the method described above can be implemented in a mirror-like manner, relative to what disclosed above, using the outer container 6 to store the refrigerant FA and, vice versa, the inner container 8 to contain the refrigerant FB, which is cooled down in order to absorb heat from the refrigerant FA. In this case, the container 8, since it is filled with cooled refrigerant FB and is drowned in the refrigerant FA, absorbs heat from the latter, thus reducing the temperature thereof and changing its state from vapour to liquid. The vapour to liquid state change of the refrigerant FA in the container 6 determines a pressure reduction, which, for the reasons discussed above, causes the transfer of the refrigerant FA from the air conditioning system 3 to the container 6.

Furthermore, the refrigerant recovery tank 2 can obviously comprise, for each container 6 and 8, beside the first terminal 5 and 7, respectively, also a second terminal 5a and 7a, respectively. In the example shown in the accompanying Figures, for example Figure 8, the first terminals 5 and 7 are adjacent to one another in the upper part of the refrigerant recovery tank 2, whereas the second terminals 5a and 7a conveniently are adjacent to one another in the lower part of the refrigerant recovery tank 2. The terminal 7a can conveniently be connected to the inner container 8 through a duct 9a, which at least partially goes through the inner chamber of the container 6.

Figure 9 shows a convenient embodiment/implementation of the system 1 described above, in which the latter comprises a maintenance station or apparatus 200 of an air conditioning system 3 of the vehicle 4 and a recovery apparatus 201.

In the example shown in Figure 9, the maintenance apparatus 200 comprises at least: the terminal 15, the suction circuit 10; the tank 11 containing the refrigerant FB; the refrigerant charging circuit 12; and the electronic control device 100.

The maintenance apparatus 200 can preferably comprise, furthermore, a control board 210, through which the operator can select and activate a specific refrigerant recovery program .

Obviously, the maintenance apparatus 200 can conveniently be manufactured according to the disclosure of Italian patent application no. 102016000081272 (UA2016A005744 ) and/or of Italian patent application no. 102016000054482 (UA2016A003839 ) , whose content is included herein as reference. The recovery apparatus 201 can have a support frame 202, which is designed to preferably - though not necessarily - support the refrigerant recovery tank 2; at least one side connector 203, which is designed to be connected to the terminal 15 of the maintenance apparatus 200 through the duct 16 and is designed to be selectively connected to the terminal 5 or 7 of the tank 2; a side connector 204, which is designed to be connected to the terminal 19 of the air conditioning system 3 through the duct 18; and a lower connector 206, which is preferably connected to the terminal 7a of the tank 2 and is designed to be connected, through an outer duct, to the tank 20.

In use, the operator connects: the connector 203 to the terminal 15 of the recovery apparatus 201 through the duct 16, the connector 204 to the terminal 19 of the air conditioning system 3 through the duct 18 and the connector 206 to the tank 20. The operator can select, through the control board 210, the refrigerant recovery program. The refrigerant recovery program can be stored in a memory device (not shown) and can be loaded and implemented by the electronic control device 100. The electronic control device 100, when implementing the refrigerant recovery program, is configured so as to cause the system 1 to carny out the operating steps described above in detail.

To this aim, the recovery apparatus 201 can be provided with an inner hydraulic circuit provided with solenoid valves, which alternatively connect the connector 203 and/or the connector 204 to the terminal 5 and/or 7 of the tank 2 during the suction operation carried out in the container 8 for the creation of the depression determining the initial transfer of the refrigerant FA into the container 8 and the suction operation in the container 6 to cause the cooling of the fluid FB contained in it.

The advantages of the system are the following. First of all, the system and the method allow any type of refrigerant be be removed from an air conditioning system, without knowing its nature.

Furthermore, the system is extremely economic to be implemented and eliminates the need to use mechanical pumps. Indeed, the system at least partly uses, for its operation, devices which are usually present inside a workshop, in particular the charging station.

Finally, it is clear that the refrigerant recovery system and the method described above can be subject to changes and variations, without for this reason going beyond the scope of protection of the invention.

According to a possible variant alternative to the embodiment described above, the method can require the cooling of the refrigerant FB to be carried out in a direct manner i.e. through a cooling device instead of in an indirect manner through the controlled reduction of the pressure thereof in the container 6. In this case, according to the accompanying Figures, the system can comprise a cooling module 13, for example a refrigerator module, which is controlled by the electronic control device 100 so as to directly cool down the refrigerant FB contained in the container 6. The cooling module 13 can further be installed in the maintenance apparatus 200, like Figure 9 shows. Obviously, according to a further variant which is not shown herein, the cooling module 13 could comprise a cooling circuit installed in the recovery apparatus 201 so as to surround, in use, the tank 2, or it could be directly installed/integrated on the tank 2.