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Housing concept for modern man 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 wrench Unscrew the blind plug from the radiator 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.
At certain intervals, air accumulates in the heating radiators.
Air pockets prevent the circulation of liquid in the heating radiators, which leads the heat transfer coefficient to zero.
For this reason, radiators cannot warm up well enough and they become cold, creating discomfort in the rooms.
Why do you need an automatic air release?
Craftsmen have always tried to solve this problem, each as best they could.
The most advanced choice was a pipe with a tap welded at a point located at the very top.
They came up with other tricks, but all this was imperfect and inconvenient to use.
In order for the system to operate at full capacity, it is necessary to bleed air from it.
It is most convenient to do this procedure using the Mayevsky tap ().
The first non-automatic model The device was developed during the Soviet Union.
To use the air vent it was necessary to have special tools.
Now, such designs are not popular.
In modern plumbing stores you can buy an automatic Mayevsky faucet for heating radiators.
It's worth it, not expensive, but can significantly make life easier for those whose home is heated through a central heating system.
The device is made in a classic version
The part has a small metal body ( the best option is brass) with a miniature funnel.
At one end of the product there is a thread for installation on the radiator opening, at the other there is a nozzle with a screw.
Since the valve is mounted in place of the limiter on the heating device, its installation is carried out at a time when there is no water in the system.
The device has an O-ring, it is necessary to ensure the tightness of the device. And the lid, in most cases, is made of plastic or nylon.
Air valves, as usual, are made from brass alloy(it is not subject to corrosion processes).
The frame itself is made of brass, and on top, as a rule, there is a plastic lining. In the inner part of the product there is a stainless steel needle shutter.
The modern market offers a wide range of products of similar mechanisms from different suppliers.
There are samples in which the plastic frame rotates horizontally; in others, the opening of the rotating casing is located directly on the edge of the needle valve nut.
The operating concept determines the internal structure. The Mayevsky tap is installed in the cap - a plug at the end of the battery or at the highest point of the heating system.
Needle choke, which is located in the core, moves inside the working sphere, and the locking element triggers the mechanism.
The position of the locking screw is set manually or using a Phillips screwdriver.
Many manufacturers complete their products with a square wrench.
It makes it much easier to adjust the tap.
It will be very difficult to do without it if the start valve is difficult to reach with a screwdriver or by hand.
Sometimes, batteries are placed in inaccessible places in the room (deep alcove).
The concept of the air action makes it possible to understand why the Mayevsky crane is needed. Without it, removing the plug from the heating system can sometimes be very difficult and extremely inconvenient.
Experts advise installing a similar device in every heating system.
When performing work on installing an air vent, you must adhere to the following recommendations:
- if the coolant is supplied from the bottom to the top, then the air valve can only be installed on radiators on the upper floors;
- when horizontal wiring is done in the house, it would be advisable to install a Mayevsky tap on each battery.
Sometimes the device is mounted on a heated towel rail.
Design features
Automatic option, much more convenient in use than normal. It has a more intricate design.
The bolt is replaced by a mechanism with:
- float,
- jet,
- spring.
The outlet is located at the bottom of the device.
When the coolant level decreases, the float begins to react to this.
He goes down, opens the needle valve slightly, and the air comes out in a thin stream.
The automatic version has the following features:
- determine the automation by its perpendicular location,
- the device can operate without human intervention,
- there is no need to place a basin to drain the liquid, since when the water level rises, the hole closes automatically;
- it can be installed on a “warm floor” system and in close proximity to the heating boiler;
- the elements of the mechanism are sensitive to the quality of the coolant,
- high cost of the product.
Since you won’t be able to monitor the quality of the liquid, and you won’t want to clean the device every month.
For this reason, the device will leak, and over time may cause a flood in the apartment.
Among other things, central heating is characterized by frequent interruptions in the supply of coolant.
In such a system much more is collected unnecessary air than in the case of an autonomous one (read about heating a private house with a heat pump).
It will take a very long time to bleed air through a 2 mm hole.
This is also an argument for not installing an automatic Mayevsky faucet on old-style cast iron radiators (read about modern heating radiators in the article).
For these purposes, there are models in which the frame is made of brass. Such a part is capable of carrying high temperature(up to 150 degrees).
Air vents equipped with a safety valve, are also installed in systems made of PVC pipes.
By installing a tap, you will prevent rupture of a sensitive structure to water hammer.
How to install in battery
To install a Mayevsky crane, you just need to screw the appropriate model into the radiator cap from the back of the water supply.
Since the sizes of the grooves on the products are standard, you need to select a device so that the threads match.
If there is a non-threaded plug at the end of the battery (), it must be replaced.
On a cast iron plug You can easily make a suitable hole with your own hands. First, you need to drill the opening from the inside, and then cut the grooves from the outside.
To do this you will need an electric drill, a 9mm drill bit and a tap with a driver.
Remember! The plug has a left-hand thread, and the tap has a right-hand thread. To ensure that the plug does not loosen during installation, it must be held with an adjustable wrench.
You should know! When you screw in the Mayevsky tap, the plug will loosen. When the air vent is unscrewed, the restrictor is tightened more tightly.
When installing a thread reinforcement device connections use a special rubber or silicone gasket.
Some plumbers use fum tape for pipes () or linen wrap - this is not necessary.
Be careful when choosing.
Take a closer look at the products, they should not have defects.
Poor quality products will crack during installation.
Remember! If the mechanism is inert for a long time, it may jam.
Then you will have to change not only the faucet, but also the radiator limiter.
What you should know when choosing
- This is such a reliable and sophisticated design that you don’t need to add anything to it.
- There is no need to pay more for a well-known brand, but too cheap products should alert you.
- The faucet frame made of steel and plastic is less reliable than that made of brass and stainless steel.
- All faucets release air equally slowly. Think about which mechanism will be more convenient for you to unscrew.
- Ask if they will give you a guarantee for this type of product.
Conclusion
The Mayevsky crane is a fairly simple mechanism and it is not expensive. By installing a faucet on the heating system of your apartment or private house, you will significantly extend its service life.
Turning on the battery, opening the Mayevsky tap, watch the video on how to do it correctly.
In some cases, air accumulates in the heating system. For open systems (with open expansion tanks) this is not a problem - it comes out on its own, but for closed systems it is necessary to remove it. As there are fewer and fewer open systems - they are considered less stable - air exhaust devices have become an integral part of modern heating. Today there are both automatic and manual models. They come in different designs, connection sizes, and are made from different materials. But they have one function - to remove gases from the heating system.
In normally designed systems, air rarely appears. Mainly after filling or refilling. If the layout is not entirely successful, suction occurs constantly. What are the dangers of its high content in the system? The most unpleasant moment is that in this case corrosion is activated, the metal components of the system quickly rust and fail. The second problem: increased noise level. And third, air jams form. Therefore, automatic air vents are installed in each system at the highest point.
This is a radiator automatic air vent. It is only slightly larger than the Mayevsky faucet, costs about $2, but it removes gases on its own
Most often, gases accumulate at the tops of radiators. Then the coolant circulation in it deteriorates. And this leads to the fact that the battery is only partially heated (which part remains cold depends on the type of connection). Therefore, manual air vents are installed in each heating device (radiator, register or heated towel rail). In our country, the Mayevsky crane is most often installed.
Why do they put manual models on radiators? They take up less space and are cheaper. But there are modern special modifications of automatic devices that are only slightly larger in size. They cost more (the device is more complicated), but the air is removed on its own.
Where are radiator air vents installed? In the pipe-free upper radiator manifold.
On which radiators should gas vents be installed?
Installation on aluminum batteries is required. When aluminum comes into contact with the coolant, water decomposes into components, one of which is hydrogen. Therefore, it is necessary to vent gases in such heating devices.
It is advisable to install it partially. In them, the contact area of aluminum with the coolant is greatly reduced, but is still present. That is why the installation of the Mayevsky crane is desirable.
This is a straight and angular automatic air vent. They can also be placed on radiators, only the “pimply” should look up
Fully bimetallic radiators are safer in this regard: their entire core is made of steel. But many manufacturers require such a device in their installation recommendations.
These devices are ineffective on . In them, air removal is only possible together with a sufficiently large amount of coolant. But these devices (both manual and automatic) are not suitable for this. In this case, standard or ball valves are installed to bleed air.
With tubular radiators and registers, the situation is approximately the same as for cast iron: only taps work effectively. Therefore, there is no point in installing air vents on them.
This is a needle air vent valve, or a Mayevsky valve.
Installation of Mayevsky taps on steel panel radiators is mandatory. The fact is that the passages for coolant circulation have a small diameter. And if an air lock forms, the movement of the coolant will be blocked. It will completely or partially stop heating. The plug can be removed only by draining most of the coolant and filling it again. Therefore, most often panel radiators come straight from the factory with air bleed valves.
Types and technical characteristics
Depending on the method of removal, these devices are of two types:
- manual;
- automatic.
They are made with different diameters. The most common are 1/2” and 3/4” (half an inch and three quarters of an inch). In nature, there are also 1/8”, 1/4” and 3/8”, but they are not used in our systems. The modification most often used is a half-inch diameter 1/2”; in another system of units it is also called DU 15. In this case, the number 15 is the designation of the connection size in millimeters.
In addition to diameters, the following parameters are also important:
- Operating pressure. In most models it is 10 atm, there are devices designed to operate at 16 atm.
- Type of work environment. There are air valves, and there are those that handle liquids. Heating systems use working liquids or universal ones (both air and liquid).
- Temperature of the working environment. More often they are found with an operating temperature of 100 o C - 110 o C. There are those operating up to 150 o C.
- Thread type: external or internal.
These specifications air vents must be selected for the existing type of system. For individual heating systems, any will be suitable, but when selecting devices for radiators powered from centralized systems, you need to know both the pressure and the temperature specifically for your home (find out at the housing department, housing department, housing office, etc.).
Operating principle of automatic air vent
The designs of these devices may change, but the principle of operation remains the same. The device is a hollow cylinder, which consists of two parts - upper and lower. They are connected to each other using a thread, the tightness is ensured by a rubber (silicone) sealing ring. At the top there is a small hollow cylindrical protrusion. Air leaves the system through this protrusion. It has a thread onto which a plastic (polypropylene) cap is screwed. With this cap, you can stop bleeding air if desired (tighten it).
One of the devices is simple and effective
The operation of the automatic air valve is based on the buoyancy of a float placed inside. The float is connected to a rod that acts on a spring-loaded spool that closes the outlet. If there is no air in the system, the air vent body is filled with coolant, the float has risen up. In this position, the rod supports the spool, and air does not come out (or come in). When air appears in the system, the coolant is gradually displaced and the float moves down. The rod does not press as hard on the spool, and the spring opens the outlet hole. The accumulated gas escapes, coolant is again drawn into the housing, and the valve closes.
In devices from different companies, the mechanism for influencing the spool may be different, but the principle remains the same: the float is down, the valve is closed, when it rises, it is open. The operating principle of one of the modifications is demonstrated in the video.
Types of automatic air vents and their installation
These valves can be straight or angled, and there are special models for radiators. Specialized or angular modifications are often installed on batteries. They are screwed into the radiator manifold (if the diameter allows) or installed through an adapter.
Regardless of the type, the device must be installed so that the outlet (cap) is directed upward. There are two installation methods:
The shut-off valve has a spring-loaded gasket inside, which, when released, shuts off the coolant. When installing the air vent, the valve is pushed down, opening access to the system. It is very desirable to install this simple device in centralized heating systems. It allows you to remove air vents without stopping and draining the system. You will have to remove them for cleaning. IN shared systems the coolant has many impurities that settle and clog the spool and the mechanism supporting it. If a lot of dirt accumulates, coolant begins to flow through the outlet hole. This means it's time to disassemble it and clean it. This is where the shut-off valve comes in handy. With it, you simply unscrew the air vent device, the spring is released and the hole is sealed with a gasket.
When installing an automatic air vent there are several rules:
A little about prices. It has a significant variation and depends on the manufacturer, connection diameter (half-inch ones are about 10-15% more expensive), as well as on the material used. The cheapest models cost about $5, the most expensive - $15. But in different stores prices for the same models can vary greatly. For example, you can buy a Danfoss DU 15 automatic air vent for both $7.63 and $11.5. But, of course, you need to look carefully so as not to buy a fake. This is especially dangerous with well-known companies: Danfoss (Danfos), Wind (Wind) or Valtec (Valtek).
We also list prices for shut-off valves. There is also a spread, but not so significant: from $1.1 to $1.8.
Manual way to remove air from batteries
And yet, more often manual models are installed on radiators. And the most common of them is the Mayevsky crane. It is small, simple and effective. It is also called a needle air vent valve.
It is a metal washer with a thread applied around the circumference. The washer has a through cone-shaped hole with threads. The hole diameter is very small. On one side 1-1.5 mm (towards the radiator) and about 5 mm on the other.
Diagram of the Mayevsky crane
A locking cylinder is screwed into the hole, which is also threaded. When closed, it blocks the coolant flow completely. The cylinder is unscrewed, the cone is lifted, the hole opens. If gases have accumulated in the radiator, they come out. If there are no gases, the coolant comes out. But there cannot be a lot of it: not much will leak into a hole with a diameter of 1 mm.
In some models, a plastic disk with a drain hole (also about 1 mm in diameter) is attached to the body. This disk turns freely around a horizontal axis, which allows you to set the drain hole in a convenient position.
How to use the Mayevsky crane
If you have air collected in your heating radiator, you need to take a special wrench (a small piece of plastic that comes with each kit) or a regular screwdriver. Insert it into the slot on the air vent disc and turn it one or two turns counterclockwise. At the same time, a hissing sound will be heard - air begins to escape through a small hole next to the disk. Gradually, water begins to come out along with the air (the stream is very thin, don’t be alarmed). When the stream becomes continuous, close the tap by turning the key (screwdriver) in the opposite direction.
This procedure is usually needed when starting up the system, and from time to time throughout the year. After the end of the heating season, you also need to check for the presence of gases - it is forbidden to drain the coolant, since “dry” the inner surface of the radiator very quickly corrodes. And since the coolant remains in the radiator, reactions continue to occur. What you can do to remember to bleed the air is to turn the tap a little after turning off the batteries. Then there will be a small hole through which, without pressure, water (coolant) will not flow, and the gases will gradually escape.
Another option for a manual air vent
This valve is produced by the same companies that make automatic valves. There is also a cone here, but the design of the device is somewhat different. In addition there is a handle. It is, of course, more convenient to use than a key. The principle of operation is similar: turn in one direction, the cone moves away from the hole, the air comes out. Turned it in the opposite direction and closed the hole.
A little about prices. The price of the Mayevsky faucet is $1.2-1.5, manual valves of other types start from $2. It’s hard to say how much the most expensive one might cost, but there are “antique” models that offer to buy for $20.
How to install manual models
The Mayevsky tap is screwed into the adapter. Usually there are no problems with selecting diameters, since this device comes in a mounting kit for radiators. Only during assembly you need to remember that if you install it on the radiator on the left, you must first screw the air vent into the adapter and tighten the threads (with a regular wrench, without using excessive force). After this, you can screw the assembly into the manifold. The whole installation.
Another version of the manual device is no more difficult to install. The process is the same as when installing an automatic one. In this case, it is also desirable to install it in tandem with a shut-off valve (the Mayevsky valve cannot be removed without stopping the system). If you are installing with a valve, screw the valve into the adapter from the installation kit. Then install this assembly on the radiator. And then you can screw the air vent into the installed valve.
Sometimes, to ensure tightness, winding is screwed onto the thread. You just don’t need to wrap it around a lot, and you can’t use paint. It is better to take a little sealant (you can only use sealant).
How the Mayevsky crane is installed is demonstrated in the video.
Results
In properly designed systems, it is quite sufficient to install manual water vents to remove air from radiators. If gases accumulate regularly, it is easier to install automatic devices and not constantly check whether the batteries are heating up, or whether it is time to release the accumulated gases.
Dissolved air enters the heating system along with the coolant. Accumulating in significant quantities, oxygen creates plugs that prevent normal fluid circulation. This reduces the quality of heating of the building. To eliminate airing of the system, a Mayevsky crane was designed. The principle of operation is simple and clear, so such a device is installed everywhere - be it a multi-storey building or a modest cottage.
Purpose of the Mayevsky crane
Air is lighter than water, so it accumulates at the peak points of the space heating system and radiators. This happens for several reasons:
- pipes do not fill with water quickly enough;
- the fed system was partially empty;
- There is a lot of dissolved oxygen in water.
Sometimes the accumulation of air provokes a special design of the heating system, when in certain areas loops of pipes are formed, turned upward.
In 1931, the State Planning Committee decided that during downstream installations, ordinary taps should be installed to remove air from systems. But through them, residents of houses not only eliminated air locks, but often drained hot water, which in this case acts as a coolant, and then used it for household needs - for example, to wash the floors. This was unacceptable from the standpoint of sanitation and the technology of central heating of buildings. Therefore, Mayevsky taps began to be installed on radiators, which significantly complicated the task of inappropriate use of coolant.
How the Mayevsky crane works
The device was developed in 1933 by an engineer from Leningrad, Cheslav Bronislavovich Mayevsky. Officially it is called a radiator needle air valve.
According to some historical data, the crane of Minsk resident S.A. Roev first appeared. It consisted of two parts separated by a gasket. The devices were tested in 1932. A year later, Mayevsky improved this design, improving the sealing of parts. In a more modern interpretation, the engineer connected the parts using the “cone-to-cone” method.
The crane consists of the following components:
- frame;
- conical head screw;
- turning part;
- inlet and outlet channels for air.
The air vent device drives the locking screw. The latter is controlled with a screwdriver or manually, which depends on the specific model. In the modern version, a special key is already installed on the tap, so using the device has become easier.
Advantages of installing a Mayevsky crane:
- increasing the coefficient useful action heating network;
- simplification of radiator maintenance;
- affordable cost of the unit itself.
But such a crane, despite the listed advantages, also has a drawback. Since the quality of the coolant often leaves much to be desired, blockages often occur in the tap during operation.
Depending on the design, there are three types of crane:
- radiator- intended for heating devices;
- traditional- can be installed everywhere, equipped with an external thread;
- complete- is a ball valve with KM.
Depending on the method of unscrewing, there are the following devices:
- for a screwdriver;
- turnkey four- or hexagonal;
- with a handle, which does not require a tool.
Various materials and their combinations are also used for manufacturing. There are CMs:
- steel;
- brass;
- cast iron;
- stainless steel;
- plastic.
Most often, the assembly is made from brass, which is resistant to corrosion, which threatens the materials due to unfavorable operating conditions. Often, unscrupulous sellers pass off cheap silumian as brass. But this material is unreliable, products made from it quickly fail.
Attention! Children love to play with various objects. Therefore, it is better to install a tap in their room that can be opened with a screwdriver. If the baby opens the tap on his own, he will get burns.
Automatic KM
Automatic CMs are convenient in private homes with individual heating, as they eliminate air locks and regulate the pressure independently. Inside this unit there is a chamber equipped with a float inside. This, in turn, is connected to a needle valve located at the top of the assembly.
When the air gap exceeds the set limit, the valve opens for a while, allowing air to leave the system. Then, due to the action of the float, it returns to its original position again, preventing water from flowing out.
The main advantage of AKM is that there is no need to place a container to remove air trapped inside the pipes, since water does not flow out. The tap is automatically blocked as soon as the coolant level rises. However, automatic models are more expensive than mechanical ones.
Air vents are:
- straight;
- corner;
- radiator.
Video - Mayevsky crane: what it is and how it works
Where to install the device?
The device is installed at the highest points of the premises network. However, in addition, the installation diagram of the heating network is taken into account.
The vertical method of supplying coolant requires that each radiator located on the top floor, where there is a lower supply with a return line, be equipped with a KM.
Air valves are also needed everywhere on devices in which the supply line is completely or partially below the level of the upper connection axis. Then the natural elimination of the oxygen plug becomes more difficult. In the horizontal version of the circuit, the CM is placed on each heating radiator.
Air valves are also installed in areas where there are bends in the pipeline. So, for example, when a pipe bends sharply upward and then descends down a short section, a pocket is formed. Airing will constantly occur in this area. The crane is installed here at the top point of the site.
The “warm floor” system in most cases also requires the installation of this equipment. Air release is most effective on the collector group, which rises above the floor level.
“Heated floor” systems are rapidly gaining popularity among owners of private country houses and city apartments. IN We will tell you whether it is possible to connect a “warm floor” from heating.
Mayevsky taps are also installed in the towel dryer in the bathroom. This is necessary when airing occurs regularly in the system. The manufacturer provides a hole for the valve in heated towel rails connected from below. When connecting laterally, this section of the pipe is slightly modified. Then a tee with the required thread parameters is implanted into the supply zone. Install the device, directing the outlet away from the wall.
It is important! If air constantly accumulates in the pipes, then during the next repair it is worth purchasing models of towels that are already equipped with a Mayevsky tap.
What to look for when buying an air vent valve?
Heating systems are susceptible to water hammer. This happens rarely, but the possibility exists. Therefore, it is better to choose models with a safety valve that is sensitive to pressure changes. When the indicator reaches critical levels, the valve opens and water leaves the heating circuit.
Reference. Water hammer is a pressure difference that is caused by a sharp change in the speed of movement of the coolant. This phenomenon leads to the formation of cracks, ruptures of pipes and radiators, as a result of which the coolant flows out of the system and floods the premises. PVC pipes are most often damaged.
It is better to choose products with rubber or silicone gaskets. There are also paronite gaskets, but they have proven to be worse. Additionally, the thread can be strengthened with linen tow or fum tape.
When choosing a faucet, take into account its location and the design of the heating system itself.
Manual models of cranes are universal. When purchasing them, you must take into account the distance from the pipe on which the valve is installed to the wall. The distance is left such that the tool can be used, especially if this requires a screwdriver or pliers.
Automatic machines are not very suitable for centralized heating systems. There, the purity of the coolant raises questions, so the unit often gets clogged. Such models are not very suitable for cast iron radiators either. In the latter case, manual models in a brass case have proven themselves better. They can also be used in steam heating systems.
But AKMs are convenient in tight spaces and places with difficult access. They are also used in underfloor heating systems, since it is difficult to detect the formation of an air lock.
When purchasing, pay attention to the thread parameters. You should also find out the type of socket on the radiator. For sale, manufacturers offer KM models equipped with a handle with a side outlet, which are more convenient than those located in the traditional way.
Also, when choosing a node, take into account the following characteristics:
- permissible pressure;
- working temperature.
Step-by-step instructions for installing KM into the system
At the first stage, preparatory work is carried out. It is advisable to carry out the installation in the warm season, when it is possible to remove coolant from the heating system. Often in old radiators there is no special hole for the CM, so it must be drilled.
- At the first stage, the pipes are removed.
- Remove the radiator from the hooks and completely drain the water.
- On the side opposite from the pipe entrance, a hole is drilled in the top plug, the diameter of which corresponds to the purchased CM.
- The threads are cut inside according to the one used on the KM. It should be taken into account that the tap has a right-hand thread, therefore, the plug has a left-hand thread. Another option is to replace the entire plug at once.
- Then install the tap, as indicated in the instructions for the device.
- The battery is returned to its place.
- At the last stage, the pipeline is connected.
The tap outlet is directed slightly downward. This makes it easier to collect the water that should flow from the tap.
When installing the device on heating pipes made of plastic, a fitting will be required.
Attention! Valves with manual control are usually installed horizontally, automatic valves - vertically. The correct installation must be clarified in the instructions.
Video - Equipping a heated towel rail with an air vent tap
How to bleed air from a heating system?
If the coolant is driven by the circulation pump, it is turned off. At least 15 minutes must pass between stopping the equipment and starting to bleed air. During this time, oxygen will rise up.
Prepare the container that will be needed to collect water. Using a screwdriver, wrench or turning the handle, unscrew the tap until a characteristic hissing sound is heard - a sign that air is leaving the system. However, simply waiting for the hissing to stop is not enough. The water needs to flow. This means that the traffic jam has been removed. The stream should be smooth and flow without interruptions. Only after this the valve is closed.
Attention! Sometimes, even after repeated bleeding, air pockets still form. Then the cause may be a breakdown or insufficient twisting.
Features of crane operation
If the device is used correctly, the entire heating system will work correctly, and undesirable consequences will be minimized.
The taps last a long time. The problematic side of operation is that they often become clogged. Then the equipment is cleaned. A needle is used for this.
The problem area can be detected independently at home without the involvement of a specialist. The method is quite simple, and you only need a piece of paper. The valve is left open to allow air to escape. Take a sheet of paper in your hands and pass it at a distance of 1 cm over all places where there are connections and along pipes and radiators. In an area where there is no seal, the paper will stick.
This area is carefully inspected and the cause of the air leak is determined. Then the system is serviced and the failed element is replaced.
It happens that the air vents have not been used for a long time. Then the tap thread may oxidize, making it impossible to remove air from the heating pipes. To get rid of rust, use WD-40 or similar products. Then lightly tap the surface and try to open the valve.
Is it possible to do without air exhaust devices?
It is possible to get rid of air bubbles by supplying water to the top plug of the battery from above. However, the speed of movement of the coolant should not exceed 25 cm/s. For faster handling, a Mayevsky crane will be required.
When supplying water from below, sometimes the risers continue behind the outer radiator of the last floor with pipes connected to common air collectors. The implementation of this model requires large material costs due to the increase in pipe footage.
Devices have been developed that can replace the Mayevsky crane.
Table 1. Crane analogues
| Device name | Peculiarities |
|---|---|
| Water taps | The device differs significantly in design and application from the Mayevsky crane. The system is filled with water through water taps and emptied. The initial tap is used to supply water, the final tap is used to remove it from the network. |
| Vertical outlet with empty expansion tank | This device is installed when the pump is not in use. Expansion tanks are a container that is designed to allow excess water to flow into it, which is formed when the coolant expands due to heating. Expansion tanks can be open or closed. |
Reference. They try not to install Mayevsky taps on ionic systems with closed circulation. To speed up the circulation of the coolant, a brine solution is added to it. When bleeding air, salts will settle on the parts of the assembly, so the service life is reduced.
Some technicians with experience in servicing heating systems even do without air vents. They eliminate the formed gas plugs through the thread of the upper connection. However, carrying out such work takes some time and requires the development of professional skills.
Is an air vent needed in a heating system or can it be done without? You can understand this by exploring the network. If it is obvious that oxygen is collecting and cannot escape, a valve will have to be installed.
The heating system has the negative property of accumulating air in the pipelines, which prevents hot water from circulating fully. This leads to the fact that radiators reduce heat transfer to the premises of an apartment or house. Dozens of years ago, a special faucet was invented, with the help of which you can ventilate the heating system without unnecessary hassle. Installing a Mayevsky tap allows you to increase the efficiency of heating appliances. This device is structurally simple and easy to install.
Operating principle of the Mayevsky crane
The Mayevsky tap is essentially a shut-off valve, which has several modifications. Depending on the installation location of the air vent, a plumbing part of a certain design is selected. The most popular material for faucets is brass, which does not corrode. For this reason (and thanks to the design features) Mayevsky cranes are reliable and durable.
In a heating system with vertical branching, such installations are mounted on all devices located on the upper floor. In a situation with a horizontal system, taps are installed on all radiators. The Mayevsky faucet is also installed on the heated towel rail, but before installation it is necessary to install a tee in the right place. The device is installed in a vertical area with the hole directed away from the wall.
After installing the taps, you need to ventilate the entire system. This procedure occurs in a certain sequence.
- It is imperative to prepare a container into which water will be poured through the hole after the air has left the system.
- Air is then removed from the heating system, which is lighter than water and therefore accumulates in the upper parts of the appliances. Using a wrench, a screwdriver or your hand (depending on the design of the tap), the Mayevsky tap is turned counterclockwise one turn. After this, a hissing sound will be heard - this means that air begins to escape from the battery. To speed up the process, you can turn the device a little more. After some time, when the air leaves the network, water will flow through the hole. This means that the system in a particular place is de-aerated and the valve can be closed.
- If pumps are installed in the house and the system operates from them, then the units must be turned off before releasing air. The air must have time to rise to the top of the radiator before it is removed from the heating system.
Installation of Mayevsky crane
To place the Mayevsky crane at its permanent location, no special experience or knowledge is required from a person. The main thing is that the tap matches the size of the inlet. These plumbing fixtures can be ½" or ¾" threaded. The tap is connected to the radiator in its upper part, and the hot water inlet should be on the opposite side.
- Before carrying out work related to the installation of taps, the water from the heating system must be drained first into a suitable container and then into the toilet.
- In radiators that have been manufactured recently, holes are made in the plugs specifically for taps, which greatly facilitates installation. If the radiator has a plug of a different design, then it can be dismantled and a more suitable shaped part installed.
- The tap must be installed on the battery in such a way that the hole is turned away from the wall, while it should be slightly inclined downwards. This arrangement will make it possible, when releasing air, to place a suitable container under the hole and drain some of the water.
The Mayevsky crane can be installed manually or automatically. It all depends on the choice of the owner, which may be influenced by the design feature of the heating system.
If the batteries are cast iron and old, then before installing the faucet you will need to do preparatory work. The following information must be taken into account:
- when installing an air vent on such a radiator, you need to make a hole in the plug on top, cut a thread in it, and then screw in the tap;
- if old radiators are part of the central heating system, it is not advisable to install taps on the machine. In such networks, hot water is not clean, so there will be constant problems with automatic air vents - the taps will have to be cleaned regularly. In addition, when the heating is periodically turned off, air pockets will often appear in the system;
- in central heating systems Periodically, hydraulic shocks occur, the force of which can reach 15 atmospheres. In this regard, automatic cranes need to be installed with a special design. The video shown clearly shows how the Mayevsky crane is installed.
Faucet care
Mayevsky cranes are characterized by reliability, so for many years no special claims have been made against them. The biggest problem is that the holes in the part sometimes become clogged. This happens when the hot water is not clean. In this case, basic cleaning is required. Contaminants can also get inside the case or into the plastic lining. In this case, you can use a regular hairpin or needle for cleaning. If the tap has become unusable, it must be replaced, not forgetting to drain the water from the heating system. This work can be done using an adjustable wrench, and during dismantling you need to fix the radiator plug in a static position and make sure that it does not loosen when unscrewing the plumbing fixture.
Installing a tap on a convector, radiator or heated towel rail is a quick procedure at low cost and it is not surprising that this part completely pays for itself. This increases the efficiency of the heating system.
Video
The video will tell you what a Mayevsky crane is and how to install it.