The basic rule for the efficient operation of water heating with a gas, electric or solid fuel boiler is good circulation of the coolant and the absence of air in the system. This is due to the fact that air creates traffic jams, and it itself does not have good thermal conductivity and heat capacity. Therefore, it must be removed using special devices - needle-type taps.
What is a Mayevsky crane
An air vent valve is an element of shut-off valves, the design of which is designed in such a way that it allows, without blocking the heating system, to remove air from it by manually unscrewing the screw with a conical end.
The term "faucet" does not quite fit the definition of the device, since it is not designed to block the fluid passage. Mayevsky's faucet is a valve and at the same time a sensor with which a person bleeds air himself. This type of device works when there is pressure in the system.
The concept of Mayevsky's crane is found only in domestic non-specialized sources. professional as wellforeign literature calls this device a needle-type air valve for radiators. They come in different shapes, but the internal structure does not differ fundamentally.
Scope of application
Each node of the heating system can accumulate air, especially it lingers in places with sharp turns, drops in the pipeline from top to bottom, in the area of changing the section from larger to smaller, in radiators.
All these areas need to be aired out, which is the direct purpose of the Mayevsky crane. But it is not convenient to mount it everywhere.
The main difficulty is that the faucet must be serviced by a person, so it is customary to embed it in those places of heating where it is easy to get to and where nothing interferes with working with a screwdriver. Main installation points:
- Heating radiators. The Mayevsky crane is suitable for cast-iron radiators, steel and duralumin.
- Homemade steel heating registers.
- Expansion tank for pressurized heating system.
- Water heated towel rail.
- High heating point, such as riser cul-de-sacs, where air can accumulate.
In addition to the Mayevsky faucet, the system must be equipped with automatic vent valves. This is due to the use of circulation pumps, which forcibly distill the coolant. Together with them, air plugs will drift along the contour, and it is simply impossible to catch them with a needle valve.
How a faucet works
Kran Mayevsky device is quite simple. It consists of:
- body;
- locking screw.
The body (base) is made of brass or bronze. Outside, it has a thread for connection to the points of the heating system. The thread is usually half an inch or three quarters, but inch threads are sometimes found. Also on the crane there is a hexagon for an open-end wrench for the possibility of installation and dismantling. Inside the case, a thread is cut, which ends in a smooth cone. There are also two holes: one for calibration for air inlet from the system, the other for bleed.
The screw is made of stainless steel and has a fine pitch thread. It is equipped with a head, usually with a slot for a flat screwdriver. Sometimes the head is made in such a way that it is convenient to rotate it with your fingers. On the other side of the screw, where the thread ends, there is a cone. It is carefully sanded to match the cone in the body without letting water through.
Sometimes the case can be supplemented with a plastic sleeve that rotates freely around it. In this case, the drain hole is located in the coupling. It is combined with a channel in the body. This makes it possible to divert air in any direction by turning the clutch. Thus, by de-airing the system, you can avoid splashing walls or valuable items with water.
Operation principle
The principle of operation of the Mayevsky crane is based on the property of air due to its lower density to rise up. Water displaces air and it accumulates in places such asvarious branches, dead ends, often making air jams here. These areas are the first to be equipped with needle valves.
Gas is directly adjacent to the calibration valve inlet. On the other hand, the channel is closed by a cone of a locking screw. When the screw is loosened, there comes a point where the calibration hole channel connects with the drain hole channel, and air can be released.
Since modern heating systems operate under pressure, the pressure begins to rush water to the open channel of the Mayevsky tap. Water, respectively, presses on the air and displaces it, after which it itself rushes out. Due to the small cross section, its losses in this case are minimal.
When water has gone through the drain hole, the screw is screwed back, the channels are blocked, and the system returns to its original state. With the subsequent formation of an air lock, the whole cycle is repeated.
Installation rules
By its nature, air tends to rise, which is also observed in heating pipes. And if he got into a closed space, that is, when there is only an exit through the lower position of the pipe or radiator, he will not go anywhere and forms an air lock. Such a plug can simply occupy part of the radiator, and it will not heat up well.
Therefore, Mayevsky cranes are installed based on the following principles:
- For each radiator of the heating system in the upper extreme corner opposite the water supply point.
- At the top of the expansiontank.
- At the top of the heating system at end points or cul-de-sacs.
Mayevsky cranes are used to supply the heating system during its installation. The shut-off screw in all taps must be screwed up to the stop. The faucet itself is installed by wrapping a sealing gasket around the thread so that there is no leakage. Most importantly, the valve must be installed in a place where there is free access to it for work on de-airing the system.
How to use Mayevsky's tap
After the heating is started and the circulation pumps have driven the coolant through the pipes, all the air that has not escaped through the automatic vent valves accumulates in bubbles around the entire perimeter of the circuit. Now it needs to be removed.
Any system consists of branches or lines. Each of them has its own beginning, the one that is closer to the boiler, and its own end, where the last radiator is installed. When airing the system with the Mayevsky crane, they always go from the first radiator to the last one. This is justified by the fact that pumps drive liquid in this direction, and the released air cannot form here again.
To work with a crane, the following tool is required:
- flat head screw driver;
- a piece of cloth to fix a leak.
The order of work is as follows:
- The outlet of the needle valve is turned away from objects that are not desirable to get wet.
- A piece of matter is brought to the hole so that inat any time it was possible to cover it and prevent a leak.
- Slowly unscrew the locking screw with a screwdriver until a characteristic hiss of the escaping air appears.
- After the air has escaped and water began to seep in, tighten the screw, eliminating smudges.
After passing all Mayevsky's cranes on batteries of one line, they move on to the next, and so on until the end. After warming up the system, go through and try the temperature uniformity on each battery. If there are poorly heated ones, the air is removed from them again.
Product advantages and disadvantages
The needle valve is a fairly reliable device, it is:
- easy to maintain for any user;
- has a simple design, the principle of operation of the Mayevsky crane is clear;
- durable and virtually clog-free;
- refers to cheap valves, despite its indispensability in any heating.
The biggest disadvantage of a needle valve is its inability to completely remove air, especially air that is constantly circulating through the system. Because of this, automatic air vents have to be installed in parallel.
Maintenance
Mayevsky's faucet rarely fails, but sometimes this happens if the water in the system is quite aggressive and contains a lot of s alts. In this case, it is simply necessary to carry out maintenance of the valves. At the Mayevsky crane for cast-iron radiators, the shut-off screw is unscrewed and the channels are cleaned. It is more convenient to do this when replacing the coolant.
Conclusion
It is important to remember that installing a heating system is a complex undertaking that only qualified specialists can do. If you decide to do the work on your own, it is advisable to have a reliable consultant in this matter.
