Air locks inside the heating system inevitably appear in the following cases:

• when a new heating system is being installed;
• in case of repair of the system and removal of water from it;
• when installing new radiators;
• when air is sucked into the system during its operation;
• when there is a gradual release of air bubbles from the water, which is a natural physical phenomenon;
• in the presence of corrosive processes, which are accompanied by the release of a certain amount of air. Aluminum heating radiators are especially susceptible to such processes in city apartments.

When choosing a device model, you should consider some features of radiators:

• For centralized heating systems, the best solution is to use manual taps, which can be used to bleed air at any time. It is not advisable to use automatic taps in apartments or houses with centralized heating. The coolant in such systems is highly contaminated, as a result of which the tap hole will constantly become clogged with dirt;
• Automatically controlled faucets are good in private homes with autonomous systems, because the coolant is kept clean there. It is also recommended to install automation in places with difficult access;
  Automatic air vent on battery
• If the heating device is installed in some kind of recess or niche, then access to its end may be limited. In this case, it will be impossible to unscrew the screw with a regular screwdriver. Therefore, it is recommended to use an automatic Mayevsky tap for such a radiator. Or use a special key, which is located in the same plane as the battery;
• Many rooms still use old-style cast iron radiators. In this case, it is possible to install a manual Mayevsky valve for cast iron radiators, but it is better to use special automatic air vents made of brass, which have significant strength.
  Mayevsky's manual tap on a heating radiator made of cast iron

Let's look at how to use the Mayevsky crane. To do this, it is advisable to place some kind of container under the battery and stock up on a dry cloth. Using a wrench or screwdriver, turn the locking screw counterclockwise a quarter or half a turn. Air will begin to hiss out of the system. When it comes out completely, water will flow from the tap. You must wait until the water starts flowing continuously. After this, the locking screw can be tightened.

Knowing what to do, bleeding air from the radiator is very simple.

If the air was successfully bled out, but the battery remained cold, then this is a sign of clogging. To clean a clogged battery, you will have to resort to the help of plumbers.

If the tap hole is clogged, it can be cleaned with a needle or other sharp object.

If the faucet has not been used for a long time, the rotation of the adjusting screw may be difficult due to the formation of corrosion on it. If this situation occurs, use WD-40 lubricant spray. Within a few minutes after applying it to the screw thread, it can be easily unscrewed. At the end of the heating season, it is advisable to lubricate the adjusting screw with silicone grease. In this case, the thread will not be destroyed by the influence of the coolant on it.

If you need to replace the Mayevsky tap, use two adjustable wrenches. Use one key to hold the cap on the radiator, and the second to unscrew the tap. If this is not done, then unscrewing the tap can weaken the plug and lead to loss of its tightness.

We looked at how to bleed air from the system using a Mayevsky valve yourself and how to operate an automatically controlled device. If you provide the necessary care to this device, check it and clean it in a timely manner, the device will serve for a long time without causing any problems to its owners.

The price of a Mayevsky crane depends on its type, material of manufacture, diameter, and starts from 30 rubles.

The Mayevsky manual tap is a self-sealing device. The product kit includes an O-ring made of rubber, so there is no need to use any additional sealing materials.

Traditionally, the installation of air vents of this type is performed in conjunction with radiator liners (1 dm x ½ dm; 1 dm x ¾ dm). As an installation tool, use a spanner wrench specially designed for working with fittings and plugs.

Plumbing socket wrench for installing radiator casings and plugs. 1 – ring wrench, 2 – radiator cap, 3 – radiator cap. These tools and parts are often used when installing air vent valves

The operation of Mayevsky valves (air vents) is permissible only at certain pressures and temperatures. These values ​​are determined by the technical characteristics of the device.

Often in city apartments the temperature begins to drop due to the fact that the heating radiators heat up poorly. This happens due to airing of the system, because the heated coolant does not enter the device in full. For such cases, the Mayevsky crane is intended, the principle of operation of which we will consider in this article.

Mayevsky crane principle of operation (diagram)

Note! This is a generally accepted name, however, both in GOSTs and in various educational books this device is referred to as a needle air valve.

Let us add that this device has played an important role in heating systems for many years, because it was invented back in the thirties of the last century. Both then and today, the tap is used to remove air pockets from batteries.

Procedure for installation and operation of the Mayevsky crane

The Mayevsky crane, the principle of operation of which was discussed in this article, can be installed with your own hands. You just need to remove the side plug, which is located on the heating radiator. Then you need to screw in the device instead of the removed plug.

After installing the device, you must use it correctly if you want to increase its service life. As soon as the radiators have stopped warming up evenly, you must perform the following steps to remove air.

Step 1. First, clean the area around the radiator to prevent damage to valuable property during de-airing.

Step 2. Prepare a basin or any other container for water; You will also need a screwdriver.

Step 3. Insert a screwdriver into the corresponding thread that is located on the device, then rotate it smoothly (note - only counterclockwise!).

Step 4. When you hear a sharp hissing sound (this is air leaving the heater), stop rotating. Next, wait until the air has completely left the system and a uniform stream of coolant begins to flow out. Don't be alarmed if the sounds are too loud - this is quite normal.

Step 5. Wait until the liquid begins to flow evenly. Then close the tap by turning it the same way, but in the opposite direction.

Note! Be prepared for the air to escape from the system for quite a long time. In this case, all that remains is to substitute the basin and wait until it (the air) comes out completely.

If you did everything correctly and removed the air according to the instructions above, and the radiator still does not warm up well, then most likely it is simply clogged. In this case, there are two possible ways out of the situation:

1. replace the radiator;
2. seek the help of an experienced plumber.

Design and principle of operation

As noted earlier, if the radiators are not ventilated, then the hot coolant will enter there in an incomplete amount, as a result, the performance of the devices will significantly decrease. And with a device such as the Mayevsky faucet, the principle of operation is such that air bubbles are removed from the batteries of the central heating system; for this you only need a special key or screwdriver.

Note! Such taps can be installed not only on radiators, but also on heated towel rails.

The air vents described can come in a variety of models and modifications (we’ll talk more about classification later), but they all work on the same principle. Roughly speaking, this device is a conical rod that closes the through hole after screwing. If we talk about the materials that are used for its manufacture, it is exclusively brass and steel. The fact is that these metals are the most resistant to moisture.

We also note that, despite the seemingly wide variety of variations, Mayevsky taps differ from each other only in the diameter of the external thread. It (diameter) can be:

1. 0.5 inches;
2. 0.75 inches;
3. the smallest products that were previously found in cast iron batteries, and today - in floor-type radiators.

Retail price table

The Mayevsky tap, we repeat, is a body into which a cone-shaped screw is screwed in, and, in fact, the screw itself. When liquid is supplied to the system, air pockets very often appear, and under such conditions this device is irreplaceable. The main sign that the system is air-filled is that the radiators do not warm up enough, although the liquid in the system is heated. This happens due to insufficient volume of this liquid or low flow rate.

Depending on the configuration, the devices can be opened not only with screwdrivers, but also with keys. They are threaded, and to open and release air you only need to turn it counterclockwise 1/2 turn. After this, you will hear a characteristic hissing sound, indicating the release of air. Over time, liquid will come out along with it and when it flows in a uniform flow, you can turn off the tap. Agree, even a person who is far from heating systems can cope with this, because you only need to make one turn of the screw.

Mayevsky crane disassembled

Note! The air vent is a manual device, and its use is advisable in centralized heating systems. But if such a system is individual or closed, then it is recommended to install an automatic tap that autonomously removes air as needed. But we are getting ahead of ourselves.

Operation of the Mayevsky crane is extremely simple. It does not require any specific knowledge or special equipment. Moreover, the thread here is universal, so the installation procedure will not cause any difficulties either.

How is flushing and pressure testing of the heating system done?!

Over the years, the heating system will give off less heat than at the beginning, the reason for this is scale and various deposits in it. Ways to combat this

Video - Mayevsky crane principle of operation

Classification of Mayevsky cranes

There are several variations of this device, let’s take a look at each of them.

Important points during operation

If the device has not been used for a long time, rust may form on the threads. Consequently, the screw will be difficult to turn. Then, before turning, it is recommended to treat the thread with kerosene and wait five minutes.

Main advantages of the device

Well, the Mayevsky crane - we have already discussed the principle of operation, now let’s talk about the advantages. Of course, it is not the only one - other devices (ball valves, for example) can be used for similar purposes. But the described device looks more presentable.

If you practice air exhaust without a tap, there will be a risk of flooding the neighbors below with hot liquid. And this promises not only high-profile scandals, but also material costs for compensation. And if you install a Mayevsky crane, then such problems will be completely eliminated.

A manual faucet also has advantages when compared to an automatic one. So, the latter very often become clogged with dirt and impurities from the system, which is why they may one day fail at the wrong time. But the manual tap is reliable and easy to use, and a special seal on the thread allows it to be installed on all types of batteries.

If you use the device correctly, you can quickly remove air from the system of the entire building. Finally, with such a faucet you will significantly save on heating costs, since the radiators will not be cooled due to the presence of air. This way the room will be heated constantly and evenly, and therefore there is no need to use additional heat sources.

Video - About the efficiency of the Mayevsky crane

Features of choosing an air vent

If you are interested in which faucet to choose, then, alas, we cannot say anything specific - everything in this case depends on the specific type of heating system. If the system is an individual type, then you can use any device, so rely on your personal preferences here. And if the system is central, then it is better to install a faucet with a fuse (we have already explained why above).

1. A manual device is recommended for those who can bleed air from the line themselves.
2. Fused devices, as just noted, are ideal for central systems.
3. Automatic devices are very unreliable, as they not only often clog, but also refuse to work for unknown reasons.

Note! As for the difference in price, in reality it is not as big as it might seem at first glance. For this reason, the cost factor is hardly decisive in this case.

As a conclusion

Whether to use Mayevsky taps, the operating principle of which we have disassembled, or ordinary water intake taps, is entirely up to you. Under normal conditions they will not cause any harm, but installing the Mayevsky tap during the heating season will be very difficult. Therefore, plan everything in advance, even where the circulation pump will be used. Good luck with your work!

Hello, our regular reader!

The concept of housing for a modern person necessarily includes a comfortable temperature in both winter and summer. In our climate, living in a house or apartment without heating in winter is simply impossible. The most common problem with a cold heating system is in the pipes, and to bleed it off there is a special device - the Mayevsky valve.

This is a shut-off valve of a very simple and reliable design for manual operation. It has existed for almost ninety years and is used almost in its original form to this day.

Its other names are: radiator valve, air bleed valve, the most common is Mayevsky valve. In textbooks, the name radiator needle air valve is usually used.

Purpose and scope of application

A common cause of inefficient operation of heating and cold radiators is airing. There is always air in the heating system water; it gets there in the following ways:

• dissolved air is always present in the water; it enters the system with recharge;
• enters when air is captured by the pump;
• in case of leaks;
• When corrosion occurs, hydrogen enters the water (in steel systems and in systems with aluminum radiators as well).

The Mayevsky tap is a device for bleeding air from heating systems. They are usually mounted on radiators (screwed into special holes in plugs) or at the highest points of the system.

Controls and technical characteristics

The Mayevsky tap is controlled manually - the screw is unscrewed and tightened with screwdrivers or using a special key.

The valve is designed for use in heating systems with pressures up to 1.6 MPa.

When used in systems with higher pressure or the possibility of strong water hammer, it is not reliable enough - there is a possibility of leakage.

Connection type

The valve body with external threads screws into the radiator cap or pipe fitting, like a coupling valve with external threads.

Device

A shut-off valve consists of a body with a hole on the side for air to escape and a conical screw that screws into it.

A fully tightened screw seals the hole in the faucet. The housing has a thread for screwing into a radiator cap or pipe with internal thread. A seal is placed on the housing to seal the connection. Typically, the material used for the faucet is brass. Steel products are practically never found.

Principle of operation

The principle of operation of the valve is simple: when the conical screw is unscrewed from the body, air (or water) enters the space that appears and, under the influence of pressure in the system, comes out through the side hole.

Types and designs

There are practically only two types of Mayevsky crane: manual and automatic.

The automatic valve is not very suitable for central heating systems - it gets clogged easily. This device operates without human intervention - it contains a float that opens the valve when air appears.

The manual model has a very simple and functional design, it performs one single function, so all products have the same design.

1 – brass body; 2 – working screw with ducts; 3 – nylon cap; 4 – sealing ring.

The types of valves are shown in the photo:

1. Mayevsky crane for tools (imported type);
2. Mayevsky tap at hand (imported type);
3. Domestic type of Mayevsky crane

Differences

There are fundamental differences only in the diameter of the external thread on the body: there are products with diameters of ½’’ and ¾’ (15 and 20 mm)’. There are products with a diameter of 1 inch.

The screw can be unscrewed using a screwdriver or a special wrench. The screw head has a square shape (occasionally a hexagonal or octagonal head) and a slot for a flat-head screwdriver. The key is supplied with the valve. There are models with a handle for unscrewing the screw.

The marking indicates the connecting diameter in millimeters; thread parameters are designated M10×1 - length 10 mm, metric thread pitch 1 mm.

Advantages and disadvantages

Advantages:

• simple design;
• durability;
• compactness and the ability to install even in hard-to-reach places;
• reliability;
• low price;
• stylish design.

Flaws:

• the need to release air manually - Mayevsky’s taps do not operate automatically. They are not very suitable for filling large systems - it will take a very long time to bleed the air; in places where air constantly accumulates, it is better to install an automatic air vent;
• are not intended for use in systems with pressures exceeding 1.6 MPa.

Buy valves at the store, not at the market. Preferably with a receipt. Although their design is simple and reliable, defective products still happen - they can be replaced. Do not buy steel products (if you happen to come across them); the ideal material is brass.

If there is a handle on the screw, bleeding the air will be much easier. And children at an interesting age too. Therefore, when choosing such a model, soberly assess the age and degree of playfulness of children's hands.

Don't go wrong with the case diameter.

Rules for installation and operation of the device

The technology for installing the valve in heating radiators is not particularly difficult; even an inexperienced home craftsman can tackle it.

Required tools and materials

An adjustable wrench or wrench, FUM tape, valve, radiator plug with a hole for installing an air vent.

Connection diagram

The Mayevsky faucet is usually screwed into the upper radiator plug opposite the coolant supply.

Work progress

Before starting work, it is necessary to turn off the valves at the battery connection or close the riser in an apartment building. Then drain the water. In practice, work on the heating system of a high-rise building is carried out in the summer.

Then you need to unscrew the blind plug from the radiator with a wrench and screw in a new plug. On the plug you need to check whether the seal is on; you can wind several turns of FUM tape on the thread.

Then screw in the Mayevsky tap (and also check for the presence of a seal).

Fill the radiator or system with water and check for leaks. If connections are leaking, tighten the nut and tap with a wrench.

If you have cast iron radiators with steel plugs, you can drill a hole and tap the thread.

How to deflate

During operation, the device does not require any maintenance work.

Using the tap is very simple: before opening the valve and releasing air, you need to place a bucket under the tap and cover the tap with a rag (or polyethylene). Sprays of dirty or rusty water can fly along with the air and splash the wall, curtains or furniture. Then unscrew the screw with one hand (using a screwdriver, wrench or pen), and hold the rag with the other hand. The air will come out with a hiss when water starts to drip - tighten the screw tightly.

You can clearly see the progress of work on using the air valve in our video:

Frequent errors and problems during installation

It is necessary to unscrew the screw one to one and a half turns. This is quite enough. If you unscrew the screw too much, it will be difficult to screw it back in under pressure, and quite a bit of water will spill out.

It is advisable to mount the valve in such a position that the hole is directed away from the wall and downwards - the wall will not be splashed when water is released.

When replacing the air vent, when unscrewing it, you must hold the plug with a second adjustable wrench, otherwise it will be unscrewed from the battery.

Water appears in the network quite often. Therefore, it is recommended to install air vents in each heating battery, register, U-shaped compensators with a loop turned upward, and at the highest point of the system.

The appearance of air pockets in battery radiators impairs the heating of rooms and can lead to malfunctions of the heating system. To prevent this, it is necessary to bleed the air. The task can be simplified by equipping complex areas of the thermal circuit with a Mayevsky valve - a special device for removing air.

An air lock prevents the coolant from moving along the circuit and entering remote parts of the batteries, which leads to a decrease in heating efficiency, increased pressure in the pipes and malfunctions of the heating system.

The gradual release of air from hot water circulating through the radiators is a natural and inevitable process. The rate of formation of air jams increases for the following reasons:

• air entered the system during installation, repair or replacement of individual sections;
• during purging and subsequent filling of the system during seasonal maintenance, the coolant was supplied with insufficient pressure;
• the tightness of the pipe joints is broken and air leaks occur;
• Corrosive processes occur - oxidation of the material of pipes and radiators, which releases oxygen.

If you find a blockage, you can call a plumber who will release the accumulated air. If the system is prone to airing, then calls from specialists will have to be paid regularly. This problem can be solved simply and effectively, and most importantly cheaply, by installing a Mayevsky valve in places where air locks form.

What is a Mayevsky crane?

Attempts to solve the problem of air locks in heating systems were made at the beginning of the 20th century. For this purpose, taps were actively used - they coped with the task of bleeding air, but they were often used not only for their intended purpose, but also to drain water from the heating circuit for other purposes.

Uncontrolled coolant discharge caused damage to the heating network, as it could cause the formation of additional air pockets and changes in pressure in the pipes. In addition, due to the high temperature of the water entering the radiators, the people using it could also be harmed.

Inventor Ch.B. Mayevsky, after whom the air vent is named, did not come up with the valve itself for venting air, but a method for sealing its parts. Mayevsky proposed connecting the parts of the crane cone to cone. This made it possible to maintain the tightness of the heating network unit in the closed position. In addition, this design made it inconvenient to draw water from the heating device.

The low efficiency of the heating system in most cases can be explained simply: the batteries are airy. A small amount of air enters the system, accumulates in its individual elements and interferes with the normal circulation of the coolant. Solving radiators is not difficult - just install a regular Mayevsky faucet. With its help, it is very easy to remove excess air from the system, and the amount of coolant will remain unchanged.

How does this device work?

A small cylinder is installed at the top of the radiator or in another suitable location. There is a special valve inside the cylinder, which is controlled by a screw.

The Mayevsky crane is a small device that is easy to install and operate. To service the manual model, you will need some space in the radiator niche.

If you need to bleed air from the system, simply open the valve and then close it. This is the first thing to do if the radiator or some part of the heating system warms up less than the rest. If the heating temperature in the problem area soon increases, the problem can be considered solved. If the radiator does not heat up after bleeding the air, it is most likely clogged. You will have to dismantle the radiator, wash it and install it again.

If the system is operating in mode, the circulation pump must be turned off before bleeding. If this is not done, some of the air will be entrained by the coolant flow and remain in the system. After turning off the pump, you need to wait at least five minutes, and only then open the air vent. During this time, air bubbles will rise up.

After the air leaves the system, water will flow from the tap. This will be a thin stream with a diameter of approximately 1.5 mm. Therefore, even before you start bleeding air, you should remove things from the radiator that can get wet, and also stock up on a suitable container for water. To use the Mayevsky tap, it is not necessary to drain the coolant or dismantle the radiators. Having studied the principle of operation of the Mayevsky crane, you should pay attention to the design of individual models.

Design of various models of Mayevsky crane

Mayevsky's air vent is a device in the center of which there is a needle shut-off valve. The movement of the valve is controlled by a special tetrahedral screw. The outside has a standard thread size: ½, ¾ or 1 inch. The control screw is equipped with a head with a slot for a Phillips screwdriver. In addition, it can be rotated using a special key or regular pliers. There are several models of the Mayevsky air vent. Interesting information about this useful device is contained in the following video:

Manual model

This is the simplest and most reliable device that allows you to control the amount of air in the heating system. The simplest Mayevsky crane consists of:

• durable brass body;
• steel needle valve;
• plastic casing.

The design of the device may vary: in some models the plastic casing moves in a horizontal plane, in others there is a special hole on the edge of the valve nut. In addition to the usual Mayevsky manual tap, two more varieties are produced: an automatic tap and a model with a built-in safety valve.

Mayevsky's manual tap can be installed on almost any radiator. To open it, you can use a special key, as well as a screwdriver or pliers

Design of the Mayevsky automatic crane

This device looks like a small metal cylinder with a hole in the top. Inside, in addition to the needle valve, there is also a sensor that operates on the float principle. The sensor responds to changes in the volume of air inside the tap. When a critical value is reached, the valve opens and releases the accumulated air, and then closes. For the operation of such a device, practically no human intervention is required; it is enough to simply install it in a suitable place.

Automated models are state sensitive. A narrow opening can easily become clogged, causing the valve to operate unnecessarily. You can remove such a blockage using a regular sewing needle.

What are the benefits of using a safety valve?

Mayevsky's air vent with a safety valve is a somewhat more complicated version of the manually operated model. The safety valve is sensitive to the coolant pressure in the system. If this indicator exceeds 15 atmospheres, the safety valve will open and begin draining the coolant from the heating circuit. This situation may arise in the event of a sudden, in which case the valve will prevent damage to system elements.

Whatever option you choose, we recommend that you buy all heating equipment from the Gipostroy online store - this is a time-tested supplier. So, at the link http://www.gipostroy.ru/catalog/category/klimat-i-otoplenie you can get acquainted with the current prices for heating devices and components.

How to choose the right device?

To choose the appropriate model of the Mayevsky crane, you need to assess the condition and capabilities of your heating system, as well as the features of the placement of radiators. Simple manual models are suitable almost everywhere. It should be remembered that some space will be needed to rotate the control screw: more - for working with a screwdriver or pliers, less - if the valve is opened using a special key. In radiator niches, space can be very limited.

Automated models will be very convenient precisely for such cases with limited access to the radiator, placed in a tight niche or hidden by a decorative screen. However, the use of automatic air vents is not recommended in houses with a centralized heating system.

Usually in such houses the coolant is so contaminated that the tap hole soon becomes clogged. The device will have to be cleaned once a month or more often, which will negate all the convenience of its use. In addition, interruptions in the coolant supply with centralized heating occur quite often, so more unnecessary air accumulates in such a system than with autonomous heating. The process of bleeding air through the two-millimeter hole may take too long.

For the same reasons, you should not install automated models on old cast iron radiators. For them, it is recommended to use special models in a brass case, for example, MC140 according to GOST 9544-93. This device tolerates temperature increases of up to 150 degrees and is suitable not only for systems with liquid coolant, but also for steam heating.

Air vents with a safety valve are recommended for installation in PVC pipe systems. These structures are sensitive to water hammer and installing a crane will prevent rupture. These models are also effective in central heating systems, which are often subject to sudden shocks.

Selecting a location and installation procedure

To install Mayevsky's air vent, simply screw a suitable model into the radiator plug on the supply side. Since the thread sizes on the device are standard, you must select a device with the appropriate thread. If the radiator has a plug without a thread, it should be replaced.

It is not difficult to make the necessary hole yourself on a cast iron plug. A hole should be drilled on the inside and then threaded on the outside. You will need an electric drill, a 9 mm drill, and a 10x1 tap with a driver.

The tap has a right-hand thread, and the plug has a left-hand thread. During installation, you should hold the plug with an adjustable wrench so that its thread does not loosen. It should be remembered that when screwing in the air vent valve, the plug is loosened. When unscrewing the tap (for example, to replace it), the plug is screwed in tighter.

When installing a Mayevsky tap, you should use an adjustable or gas wrench to tighten the device or hold the plug in which the tap is mounted

When installing the device, the threads should be reinforced with a special gasket. Such a gasket can be made of rubber or silicone, but it is not recommended to use paronite gaskets with a Mayevsky tap. Some prefer to additionally use linen winding or fum tape to strengthen the thread, but this is not necessary. Tip - when installing, you need to point the outlet slightly downward. This will make it more convenient to collect the water that will flow out of the radiator after bleeding is complete.

To install Mayevsky cranes, choose the highest point of the system, since the air rises upward. In this case, of course, it is necessary to take into account the design features of the heating system of a particular house or apartment.

With a vertical heating scheme, air vents should be installed on all radiators on the upper floor that have a lower supply with a return line. Mayevsky taps should also be provided to all devices whose supply (or part of it) to the riser is located below the upper axis of the connection, since in this case it will be naturally difficult to remove air from the system.

The diagram shows the installation principle of the Mayevsky tap for vertical and horizontal heating systems. A faucet is required in places where air accumulates

With a horizontal heating system, air vent valves are installed on all heating devices: radiators, collectors, etc. A heated floor system does not always require air venting, but very often such a valve still has to be installed.

The installation of an air vent on a heated towel rail deserves special attention. On models with a bottom connection there is even a special hole for this. But heated towel rails with side connections will have to be slightly modified. A metal tee with a thread of a suitable diameter is mounted on the supply line. In this case, the outlet of the air vent valve must be turned away from the wall.

To understand whether you need to install an air vent in a particular location, you should simply imagine the movement of air in the system. If it is clear that air can move freely further through the system, a valve is not needed. If air cannot leave the system naturally, you will need a special device.