AU2019286195B2

AU2019286195B2 - Device for eliminating condensate for air conditioners, air conditioner and method for eliminating condensate

Info

Publication number: AU2019286195B2
Application number: AU2019286195A
Authority: AU
Inventors: Nicola CHINAGLIA
Original assignee: Fintek SRL
Current assignee: Fintek SRL
Priority date: 2018-06-15
Filing date: 2019-06-14
Publication date: 2023-12-21
Anticipated expiration: 2039-06-14
Also published as: EP3807579B1; WO2019240670A9; EP3807579A1; EP3807579C0; WO2019240670A1; US20210254874A1; AU2019286195A1; JP2021527193A; CN112262288A

Abstract

A device (1) for eliminating condensation for air conditioners comprises a control unit (8) and a valve (9) connected to the control unit (8), the valve (9) having an inlet (10) suitable for being connected to at least one First heat exchanger (5; 6) and at least one first outlet (11; 12) suitable for being connected to at least one second heat exchanger (6; 5), wherein the control unit (8) is suitable for setting the opening and the closing of the first outlet (1 1; 12) of the valve (9) for conveying the condensation towards the second heat exchanger (6; 5).

Description

DEVICE FOR ELIMINATING CONDENSATE FOR AIR CONDITIONERS, AIR CONDITIONER AND METHOD FOR ELIMINATINGCONDENSATE

Technical Field

The present invention relates to device for eliminating condensation in air

conditioners. The present invention also relates to an air conditioner and a method

for eliminating condensation in an air conditioner.

Background

Air conditioners are devices that are normally used to cool air by means of a

refrigeration cycle.

Air conditioners comprise a refrigerant flow circuit housing a compressor, a

condenser, an evaporator and a throttling unit inserted between the condenser and

the evaporator.

In "cooling" mode, the compressor compresses the refrigerant vapour at low

temperature and low pressure and brings it, still as a vapour, to a high temperature

and high pressure. The vapour is sent to the condenser through copper pipes. The

condenser cools the vapour and then turns it into a liquid by discharging heat to

the outside air, which is heated. After passing through the condenser, the

refrigerant - now in liquid form but still at high pressure - passes through the

throttling unit, usually a capillary tube, thus changing from high to low pressure,

while retaining its liquid form. The low-pressure, low-temperature liquid is

carried to the evaporator, where it is turned into a vapour by heat absorption. It

then cools the air in the room where it is placed. The refrigerant then returns to the

compressor in vapour form and the cycle resumes.

The latest air conditioners can also work in heating mode by reversing the

direction of the refrigerant flow. In this mode, also known as the "heat pump"

method, the refrigerant flow is reversed by a four-way valve, which, in the winter,

enables a certain amount of heat to be absorbed from the low-temperature outside

air and discharged to the inside air at a high temperature.

There are air conditioners comprising an indoor unit and an outdoor unit. The

outdoor unit houses the condenser and the motor of the air conditioner; the indoor

unit, or "split" unit, houses the evaporator, and air is fed into the room through a

purpose-designed slot.

Recently "monoblock" devices have also come onto the market, which do not

have an outdoor unit, can use air or water condensation, are formed by a single

element and perform the functions of both the indoor and outdoor unit.

In both types of air conditioner, condensation forms on both the condenser and the

evaporator.

In "cooling" mode, condensation forms on the evaporator (generally housed in the

indoor unit) due to the difference in temperature compared with the humid air

present in the room. In heating mode, condensation forms on the heat exchanger

which is generally positioned outdoors once defrosted during the inverted

refrigeration cycle.

Condensation is usually collected in trays that must be periodically emptied, or

removed by the force of gravity through purpose-designed outdoor drains. Where

condensation cannot be removed through such drains, a pump must be used.

However, these systems require the presence of piping and exhaust ducts outside

of the air conditioner itself and, therefore, cannot always be implemented in

buildings where the air conditioner is installed (for example, they cannot be installed in historic buildings). Furthermore, they cannot be implemented for monoblock air conditioners, in which the two units are integrated into a single element positioned inside a room.

Any discussion of documents, acts, materials, devices, articles or the like which

has been included in the present specification is not to be taken as an admission

that any or all of these matters form part of the prior art base or were common

general knowledge in the field relevant to the present disclosure as it existed

before the priority date of each of the appended claims.

Throughout this specification the word "comprise", or variations such as

"comprises" or "comprising", will be understood to imply the inclusion of a stated

element, integer or step, or group of elements, integers or steps, but not the

exclusion of any other element, integer or step, or group of elements, integers or

steps.

Summary

Some embodiments of the present disclosure aim to eliminate the abovementioned

drawbacks by enabling condensation to be definitively removed without

increasing the overall size of the air conditioner, while avoiding the

implementation of purpose-designed drains.

The device according to the present invention enables the condensation forming

on an exchanger to be removed by moving it to the other exchanger to be

vaporised. Furthermore, the device can be installed in an existing air conditioner

simply by connecting it accordingly to the components of the air conditioner

itself.

Advantageously, the valve has at least one second outlet that is suitable for being

connected to the second heat exchanger, and the control unit is suitable for setting the opening and closing of the second outlet of the valve for conveying the condensation towards the second heat exchanger. This allows the device to be used when operating the air conditioner in both cooling mode and heating mode, and offers the guarantee that condensation will be removed and disposed of in any operating mode.

Preferably, the device comprises a pump with an inlet suitable for being

connected to the first heat exchanger and/or the second exchanger, where the

pump is suitable for conveying the condensation from the first heat exchanger

and/or the second heat exchanger towards the valve. This allows condensation to

be transferred to the valve efficiently.

Advantageously, the device comprises at least one collecting tank interposed

between the first heat exchanger and the pump and/or between the second

exchanger and the pump, where the tank is suitable for collecting the

condensation from the first heat exchanger and/or from the second heat

exchanger. The device preferably comprises at least one level sensor positioned in

the collection tank and connected to the control unit. In this way, the valve opens

towards an exchanger when a certain level of condensation is exceeded.

A preferred embodiment of the device comprises at least one nebuliser or

vaporiser positioned downstream of the valve. In particular, the valve has a third

outlet connected to the nebuliser/vaporiser.

An advantageous embodiment of the device comprises at least one humidity

sensor suitable to be positioned in a room, wherein the humidity sensor is

connected to the control unit.

Preferably, the control unit commands the opening and closing of the valve outlet

towards the nebuliser/vaporiser by means of a signal from the level sensor and/or

from the humidity sensor.

The control unit can then control the opening of the valve towards the

nebuliser/vaporiser - thus vaporising condensation to the outdoor air - if the

condensation has not been eliminated effectively by the heat exchangers or if the

humidity in the room where the air conditioner is placed exceeds a certain level.

Advantageously, the control unit is suitable to be connected to a cycle inversion

valve of the air conditioner and commands the opening and closing of the valve

outlet towards the first heat exchanger or towards the second heat exchanger

) depending on the cycle inversion. This allows the device for eliminating

condensation to operate automatically both in cooling mode and in heating mode.

According to another aspect of the present invention, there is provided an air

conditioner comprising a circuit for the circulation of a coolant fluid; a

compressor for bringing the coolant fluid from a first pressure to a second

pressure which is higher than the first; a first heat exchanger positioned

downstream of the compressor; a second heat exchanger positioned upstream of

the compressor; a throttling unit, preferably a capillary tube or a control valve,

interposed between the first heat exchanger and the second heat exchanger; and a

device for eliminating condensation according to any of the preceding claims,

wherein the inlet of the valve is connected at least to the second heat exchanger;

an outlet of the valve is connected to the first heat exchanger; and the control unit

is suitable for setting the opening and the closing of the outlet of the valve for

conveying the condensation towards the first heat exchanger.

According to a further aspect of the present invention, there is provided a method

for eliminating condensation in an air conditioner comprising a circuit for the

circulation of a coolant fluid; a compressor for bringing the coolant fluid from a

first pressure to a second pressure which is higher than the first, a first heat

exchanger positioned downstream of the compressor; a second heat exchanger

positioned upstream of the compressor; a throttling unit, preferably a capillary

tube or a control valve, interposed between the first heat exchanger and the second

heat exchanger; and a device for eliminating condensation according to any of the

preceding claims, wherein the inlet of the valve is connected to the second heat

exchanger and an outlet of the valve is connected to the first heat exchanger; the

method comprising the steps of: conveying the condensation arriving from the

second heat exchanger towards the valve, and opening the outlet of the valve by

means of the control unit for conveying the condensation towards the first heat

exchanger.

Brief Description of the Drawings

Further advantages and features of the present invention will become more

apparent from the detailed description below with reference to the accompanying

drawings, which show a non-limiting embodiment, in which:

-Figure 1 shows an operating arrangement for an air conditioner in "cooling"

mode, in which a device according to a preferred embodiment of the present

invention is inserted;

-Figure 2 shows the operating arrangement for the air conditioner referred to in

Figure 1, in "heating" mode.

Detailed Description

Figure 1 shows, with reference number 1, a device for eliminating condensation

according to a preferred embodiment of the present invention. The device 1 is

inserted inside an air conditioner 2.

The air conditioner 2 is preferably operable both in "cooling" mode and in

"heating" ("heat pump") mode. However, the device 1 according to the invention

can also be used within a "cold only" air-conditioning unit.

The air conditioner 2 comprises, in the known way, a refrigerant flow circuit 3

comprising a compressor 4, a first heat exchanger 5, a second heat exchanger 6

and a throttling unit 7, such as a capillary tube or a control valve, inserted between

the firstheatexchanger5 and the second heatexchanger6.

In cooling mode, shown in Figure 1, the vapour contained in the circuit 3 of the

air conditioner 2 is brought to a high pressure and high temperature in the

compressor 4 before moving to the first heat exchanger 5. In this mode, the first

heat exchanger 5 serves as a condenser. In the first heat exchanger-condenser 5,

the vapour is turned into a liquid by discharging heat to the outside air. Then, the

throttling unit 7 reduces the pressure of the liquid from the first heat exchanger

condenser 5 and regulates the quantity of the liquid to be sent to the second heat

exchanger6.

In cooling mode, the second heat exchanger 6 serves as an evaporator. In the

second heat exchanger-evaporator 6, the liquid absorbs heat from the room to cool

the room and is turned into a vapour. It is then redirected to the compressor 4 to

resume the cycle.

In cooling mode, condensation forms on the second heat exchanger-evaporator 6

due to the difference in temperature compared to the humid air in the room, which

comes into contact with the second heat exchanger-evaporator 6.

In the heating mode shown in Figure 2, the vapour contained in the circuit 3 of the

air conditioner 2 is brought to a high pressure and high temperature in the

compressor 4, before moving to the second heat exchanger 6. In cooling mode, the

second heat exchanger 6 serves as a condenser. In the second heat exchanger

condenser 6, the vapour discharges heat into the room to heat the room and turns

into a liquid. The throttling unit 7 then decreases the pressure of the liquid from

the second heat exchanger-condenser 6 and regulates the quantity of the liquid to

be sent to the first heat exchanger 5. In cooling mode, the first heat exchanger 5

serves as an evaporator.

In the first heat exchanger-evaporator 5, the liquid absorbs heat from the outside

air and is turned into a vapour. It is then redirected to the compressor 4 to resume

the cycle.

Also in heating mode, condensation forms on thefirst heat exchanger-evaporator

5 after defrosting as part of the inverted refrigeration cycle.

To eliminate the condensation that forms on the heat exchanger, according to the

present invention a device 1 is provided which comprises a control unit 8 and a

valve 9 connected to the control unit 8, where the valve 9 has an inlet 10

connectable to at least one first heat exchanger, which will be the first heat

exchanger 5 of the refrigeration circuit if the air conditioner is operating in heating

mode or the second heat exchanger 6 if the air conditioner is operating in cooling

mode, at least one first outlet connectable to at least one second heat exchanger,

which will be the second exchanger 6 in the refrigeration circuit if the air

conditioner is operating in heating mode or the first heat exchanger 5 if the air

conditioner is operating in cooling mode, wherein the control unit 8 is suitable for setting the opening and closing of the first outlet of the valve 9 for conveying the condensation towards the second heat exchanger.

The valve 9 is preferably a solenoid valve.

The method for eliminating the condensation according to the present invention

therefore comprises the steps of conveying the condensation from the first heat

exchanger 5 to the valve 11 and opening the first outlet 11 of the valve 9 by

means of the control unit 8 to convey the condensation to the second heat

exchanger6.

Advantageously, the valve 9 has at least one second outlet 12 connectable to the

first heat exchanger 5 so as to remove condensation both in cooling mode and in

heating mode. Advantageously, the inlet of the valve 9 is also connected to the

secondheatexchanger6.

In a preferred embodiment, the valve 9 has a third outlet 13 to convey

condensation out of the air conditioner 2. Advantageously, the device 1 comprises

a nebuliser or vaporiser 14 connected to the third outlet 13 of the valve 9 so as to

eliminate condensation by vaporising it to the outside air.

In the embodiment shown in the figures, the device 1 comprises a pump 15

positioned upstream from the valve 9. In cooling mode, the inlet 16 of the pump

15 is connected to at least the second heat exchanger 6. Where the air conditioner

2 is operable in both modes, the inlet 16 of the pump 15 is connected both to the

first heat exchanger 5 and to the second heat exchanger 6.

In the embodiment shown in the figures, a collecting tank 17 is provided to collect

the condensation from at least the second heat exchanger 6 when in cooling mode.

The collecting tank 17 is positioned upstream from the pump 15. Where the air conditioner 2 is operable in both modes, the collecting tank 17 is connected to both the first heat exchanger 5 and the second heat exchanger 6.

In this embodiment, the method includes the step of collecting the condensation

from the exchanger in the collecting tank 17 and setting the level of condensation

in the collecting tank 17 before conveying the condensation to the valve 9,

preferably by means of a pump 15.

Advantageously, the collecting tank 17 houses a level sensor 18 connected to the

control unit 8. In a preferred embodiment, the level sensor 18 comprises a two

stage float switch or an infrared level indicator.

In an advantageous embodiment, the method includes the steps of ascertaining the

humidity of the room in which the second heat exchanger 6 is placed and opening

the third outlet 13 of the valve by means of the control unit 8 to convey

condensation to a nebuliser/vaporiser 14 if the humidity is greater than a

predetermined value.

In particular, the device 1 comprises a humidity sensor 19 connected to the control

unit 8. The sensor 19 detects the humidity of the room in which the air conditioner

2 is placed if monoblock, or in which the internal unit is placed for an air

conditioner 2 comprising a second heat exchanger 6.

The figures show an air conditioner 2 operable in both cooling mode and heating

mode. In this case, the air conditioner 2 comprises a refrigeration cycle inversion

valve 20, which is usually a four-way valve attached to the compressor 4 to

reverse the direction of flow of the refrigerant in the circuit 3.

The valve 20 is connected to the circuit board of the air conditioner 2. Preferably,

the refrigeration cycle inversion valve 20 is connected to the control unit 8 of the

device 1 for eliminating condensation.

Where the throttling unit 7 comprises a control valve, the control valve is

preferably connected to the control unit 8 of the device 1 for eliminating

condensation.

The valve 9 of the device 1 for eliminating condensation is therefore controlled

according to whether the cooling/heating mode is in operation and receives a

signal from the cycle inversion valve 20.

The air conditioner 2 housing the device 1 for eliminating condensation operates

as shown below.

In the cooling mode shown in figure 1, condensation forms on the second heat

exchanger 6. The condensation is conveyed to the collecting tank 17.

In the advantageous embodiment shown, when the level sensor 18 positioned in

the collecting tank 17 indicates that a first predetermined value has been

exceeded, the control unit 8 commands the opening of the second outlet 12 of the

valve 10 towards the first heat exchanger-condenser 5. In cooling mode, the first

heat exchanger-condenser 5 reaches temperatures of around 90°C and the

condensation is vaporised and discharged through a fan commonly attached to the

first heat exchanger-condenser 5.

In an advantageous embodiment of the method according to the present invention,

the quantity of condensation upstream from the valve 9 is measured and, if the

level of condensation is greater than a predetermined value, the valve 9 is opened

by the control unit 8 to convey the condensation to the nebuliser/vaporiser 14.

In particular, if the condensation is not removed through the first heat exchanger

condenser 5, the level in the collecting tank 17 increases. When the level sensor

18 indicates that a second predetermined value has been exceeded, the control unit

8 commands the closing of the second outlet 12 of the valve 9 towards the first heat exchanger-condenser 5 and commands the opening of the third outlet 13 of the valve 9 towards the nebuliser/vaporiser 14.

Preferably, if the level sensor 18 indicates that the second predetermined value

has been exceeded for a certain time, such as one minute, the control unit 8 sends

an alarm signal and/or commands the air conditioner 2 to be switched off.

In the embodiment shown in which the air conditioner 2 comprises the

refrigeration cycle inversion valve 20, the method includes the following steps:

setting the direction of flow of the refrigerant and setting the operating mode to

cooling or heating; if the cooling operating mode applies, conveying the

condensation from the second exchanger 6 to the valve 9 and opening the second

outlet 12 of the valve 11 towards the first heat exchanger 5; if the heating

operating mode applies, conveying the condensation from the first heat exchanger

5 to the valve 9 and opening the first outlet 11 of the valve towards the second

heat exchanger 6.

In particular, when changing from cooling mode to heating mode, the cycle

inversion valve 20 changes the direction of flow of the refrigerant, which, upon

exiting the compressor 4, moves first to the second heat exchanger 6 and then to

the first heat exchanger 5, on which condensation forms. In this case, the control

unit 8 receives a signal from the cycle inversion valve 20 to close the second

outlet 12 of the valve 9 towards the first heat exchanger 5.

In the heating mode shown in Figure 2, the condensation forming on the first heat

exchanger 5 is moved to the collecting tank 17.

According to the advantageous embodiment shown, when the level sensor 18

positioned in the collecting tank 17 indicates that a first predetermined value has

been exceeded, the control unit 8 commands the opening of the first outlet 11 of the valve 9 towards the second heat exchanger 6. The condensation is fed into the room in which the air conditioner 2, if monoblock, is placed or in which the internal unit, if an air conditioner 2 comprising a second heat exchanger 6, is placed, to regulate the humidity levels.

If the humidity sensor 19 in the room indicates that a predetermined value has

been exceeded, the control unit 8 commands the closing of the first outlet 11 of

the valve 9 and the opening of the third outlet 13 of the valve 9 towards the

nebuliser/vaporiser 14.

In heating mode, as in the cooling mode, when the level sensor 18 positioned in

the collecting tank 17 indicates that a second predetermined value has been

exceeded, the control unit 8 commands the closing of the first outlet 11 of the

valve 9 towards the second heat exchanger 6 and the opening of the third outlet 13

of the valve 9 towards the nebuliser/vaporiser 14.

an alarm signal and/or commands the air conditioner 2 to be switched off.

The device according to the present invention therefore enables condensation to

be effectively removed without requiring purpose-designed drains to be fitted

when installing the air conditioner. Condensation is removed by the heat

exchangers already present in the air conditioner.

The device can be built into any type of air conditioner, whether it comprises two

units or a single unit. Furthermore, the device does not increase the size of the air

conditioner, as the control unit, the valve and the pump and collection tank, where

provided, are placed inside the air conditioner.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A device for eliminating condensation for air conditioners, the device

comprising a control unit and a valve connected to the control unit, the valve

having an inlet suitable for being connected to at least one first heat exchanger

and at least one first outlet suitable for being connected to at least one second

heat exchanger, wherein the control unit is suitable for setting the opening and

the closing of the first outlet of the valve for conveying the condensation

towards the second heat exchanger, and wherein the valve has at least one

second outlet suitable for being connected to the first heat exchanger, and the

control unit is suitable for setting the opening and the closing of the second

outlet of the valve for conveying the condensation towards the first heat

exchanger.

2. The device according to claim 1, further comprising a pump having an inlet

suitable for being connected to the first heat exchanger and/or to the second

heat exchanger, the pump being suitable for conveying the condensation

arriving from the first heat exchanger and/or from the second heat exchanger

towards the valve.

3. The device according to claim 1 or claim 2, further comprising at least one

collecting tank for the condensation interposed between the first heat

exchanger and the pump and/or between the second heat exchanger and the

pump, the tank being suitable for collecting the condensation arriving from the

first heat exchanger and/or from the second heat exchanger.

4. The device according to claim 3, further comprising at least one level sensor

positioned in the collecting tank and connected to the control unit.

5. The device according to any one of the preceding claims, further comprising

at least one nebulizer or vaporizer positioned downstream of the valve.

6. The device according to claim 5, wherein the valve has a third outlet

connected to the nebulizer or vaporizer.

7. The device according to any one of the preceding claims, further comprising

at least one humidity sensor suitable for being positioned in a room, wherein

the humidity sensor is connected to the control unit.

8. The device according to claim 6 or claim 7, wherein the control unit

commands the opening and the closing of the third outlet of the valve towards

the nebulizer or vaporizer depending on a signal arriving from the level sensor

and/or from the humidity sensor.

9. The device according to any of the preceding claims, wherein the control unit

is suitable for being connected to a cycle inversion valve of the air conditioner

and commands the opening and the closing of the outlet of the valve of the

device towards the first heat exchanger or towards the second heat exchanger

depending on the cycle inversion.

10. An air conditioner comprising a circuit for the circulation of a coolant fluid; a

compressor for bringing the coolant fluid from a first pressure to a second

pressure which is higher than the first; a first heat exchanger positioned

downstream of the compressor; a second heat exchanger positioned upstream

of the compressor; a throttling unit, preferably a capillary tube or a control

valve, interposed between the first heat exchanger and the second heat

exchanger; and a device for eliminating condensation according to any one of

the preceding claims, wherein the inlet of the valve is connected at least to the

second heat exchanger; an outlet of the valve is connected to the first heat exchanger; and the control unit is suitable for setting the opening and the closing of the outlet of the valve for conveying the condensation towards the first heat exchanger.

11. The air conditioner according to claim 10, wherein the inlet of the valve is

connected to the first heat exchanger, an outlet of the valve is connected to the

second heat exchanger, and the control unit is suitable for setting the opening

and the closing of the outlet of the valve for conveying the condensation

towards the second heat exchanger.

12. The air conditioner according to claim 10 or claim 11, wherein the inlet of the

pump is connected to the first heat exchanger and/or to the second heat

exchanger for conveying the condensation arriving from the first heat

exchanger and/or from the second heat exchanger towards the valve.

13. The air conditioner according to any one of claims 10 to 12, further

comprising a coolant cycle inversion valve, wherein the control unit

commands the opening and the closing of the outlet of the valve of the device

towards the first heat exchanger or towards the second heat exchanger

depending on the cycle inversion.

14. A method for eliminating condensation in an air conditioner comprising a

circuit for the circulation of a coolant fluid; a compressor for bringing the

coolant fluid from a first pressure to a second pressure which is higher than

the first, a first heat exchanger positioned downstream of the compressor; a

second heat exchanger positioned upstream of the compressor; a throttling

unit, preferably a capillary tube or a control valve, interposed between the first

heat exchanger and the second heat exchanger; and a device for eliminating

condensation according to any one of the preceding claims, wherein the inlet of the valve is connected to the second heat exchanger and an outlet of the valve is connected to the first heat exchanger; the method comprising the steps of: conveying the condensation arriving from the second heat exchanger towards the valve, and opening the outlet of the valve by means of the control unit for conveying the condensation towards the first heat exchanger.

15. The method according to claim 14, further comprising the step of ascertaining

the quantity of condensation upstream of the valve and if the quantity of

condensation is greater than a predetermined value, opening the valve by

means of the control unit for conveying the condensation towards a nebulizer

or vaporizer.

16. The method according to claim 14 or claim 15, wherein the air conditioner

comprises a coolant fluid cycle inversion valve for causing operation of the air

conditioner in cooling or heating mode, wherein the inlet of the valve of the

device for eliminating condensation is connected to the first heat exchanger

and wherein an outlet of the valve is connected to the second heat exchanger,

the method further comprising the steps of: determining the cooling or heating

operating mode of the air conditioner; if the mode is cooling, conveying the

condensation arriving from the second heat exchanger towards the valve and

opening the second outlet of the valve towards the first heat exchanger; if the

operating mode is heating, conveying the condensation arriving from the first

heat exchanger towards the valve and opening the first outlet of the valve

towards the second heat exchanger.

17. The method according to any one of claims 14 to 16, further comprising the

step of ascertaining the humidity of the room in which at least the second heat

exchanger is located and opening the valve by means of the control unit for conveying the condensation towards a nebulizer or vaporizer if the humidity is greater than a predetermined value.

18. The method according to any one of claims 14 to 17, further comprising the

step of collecting the condensation arriving from the first heat exchanger

and/or from the second heat exchanger in a collecting tank and ascertaining

the level of condensation in the collecting tank before conveying the

condensation towards the valve, preferably by means of a pump.