What is a Mayevsky crane, why is it needed and how to install it correctly
The low efficiency of the heating system in most cases is simply explained: the batteries are air-conditioned. A small amount of air enters the system, accumulates in its individual elements and interferes with the normal circulation of the coolant. Decide airing problem radiators are not difficult - just install a regular Mayevsky crane. Using it, it is very easy to remove excess air from the system, while the amount of coolant will remain unchanged.
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How does this device work?
A small cylinder is installed at the top of the radiator or in another suitable place. Inside the cylinder is a special valve that is controlled by a screw.
Mayevsky crane is a small device that is easy to install and operate. To service the manual model, you need some space in the niche of the radiator
If you need to bleed air from the system, the valve is simply opened and then closed. This is the first thing to do if the radiator or some part of the heating system is warming weaker than the rest. If soon the heating temperature in the problem place has risen, the problem can be considered resolved. If the radiator does not heat up after bleeding air, it is most likely clogged. You will have to dismantle the radiator, rinse it and install it again.
If the system is operating in forced circulation, turn off the circulation pump before venting. If this is not done, part of the air will be entrained in the flow of coolant and remain in the system. After turning off the pump, wait at least five minutes, and only then open the air vent. During this time, air bubbles rise up.
After the air leaves the system, water will flow from the tap. It will be a thin stream with a diameter of approximately 1.5 mm. Therefore, even before starting to bleed air, you should remove things that might get wet from the radiator, as well as stock up with a suitable water tank. To use the Mayevsky crane, it is not necessary to drain the coolant or dismantle the radiators. Having studied the principle of operation of the Mayevsky crane, attention should be paid to the design of individual models.
The device of various models of the Mayevsky crane
The Maevsky air vent is a device in the center of which is a needle shut-off valve. The movement of the valve is controlled by a special tetrahedral screw. Outside there is a thread of standard size: ½, ¾ or 1 inch. The control screw is equipped with a slotted head for a Phillips screwdriver.In addition, it can be rotated using a special key or conventional pliers. There are several models of the Maevsky 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 verge of the valve nut. In addition to the usual Mayevsky manual crane, two more varieties of it are produced: an automatic crane and a model with an integrated safety valve.
The Mayevsky manual crane can be installed on almost any radiator. To open it, you can use a special key, as well as a screwdriver or pliers
The design of the automatic crane Majewski
This device looks like a small metal cylinder, in the upper part of which a hole is made. Inside, in addition to the needle valve, there is also a sensor that works on the principle of a float. The sensor responds to changes in the volume of air inside the valve. When a critical value is reached, the valve opens and releases the accumulated air, and then closes. For the operation of such a device, human intervention is practically not required, just install it in a suitable place.
Automated models are state sensitive coolant. A narrow opening can easily clog, resulting in unnecessary valve actuation. You can eliminate this clogging with a regular sewing needle.
What gives the use of a safety valve?
Majewski air vent with safety valve is a somewhat complicated version of the manual model. The safety valve is sensitive to the pressure of the coolant in the system. If this indicator exceeds the mark of 15 atmospheres, the safety valve will open and begin to lower the coolant from the heating circuit. This situation may occur in case of sudden water hammer, in this case, the valve will prevent damage to system elements.
How to choose a suitable device?
To choose a suitable model of the Maevsky crane, it is necessary to assess the condition and capabilities of your heating system, as well as the features of the placement of radiators. Simple models on manual control are relevant almost everywhere. It should be remembered that for the rotation of the control screw you will need some space: more - to work with a screwdriver or pliers, less - if the valve is opened using a special key. In niches for radiators, space can be very limited.
Automated models will be very convenient precisely for such cases with limited access to a radiator placed in a tight niche or hidden by a decorative screen. However, the use of automatic air vents is not recommended in homes with a central heating system.
Typically, in such houses, the coolant is so dirty 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 flow of coolant during centralized heating occur quite often, therefore in such a system more unnecessary air accumulates than with autonomous heating. The process of bleeding air through a two-millimeter hole may take too much time.
For the same reasons, do 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 a temperature increase of up to 150 degrees and is suitable not only for systems with a liquid coolant, but also for steam heating.
On old cast-iron radiators, it is recommended to install special models of the Mayevsky crane, which are made of brass and have increased strength
Air vents with a safety valve are recommended for installation in PVC pipe systems. These designs are sensitive to water hammer and installing a crane will prevent tearing. These models are also effective in district heating systems, which are often subject to sudden differential pressure.
Site selection and installation procedure
To install the Maevsky air vent, simply screw the suitable model into the radiator cap on the supply side. Since the thread sizes on the device are standard, you need to select a device with the appropriate thread. If a plug without thread is installed on the radiator, it should be replaced.
On a cast-iron plug it is not difficult to make the necessary hole yourself. Drill a hole on the inside and then cut the threads on the outside. You will need an electric drill, a 9 mm drill, as well as a tap with a 10x1 screwdriver.
The faucet has a right-handed thread and the plug is a left-handed one. During installation, hold the plug with an adjustable wrench so that its thread does not loosen. It should be remembered that when screwing in the vent valve, the plug loosens. When loosening the tap (for example, for replacement), the plug is screwed in more tightly.
When installing a Mayevsky crane, use an adjustable or gas wrench to tighten the device or hold the plug in which the crane is mounted
When mounting the device, the threads should be strengthened with a special gasket. Such a gasket can be made of rubber or silicone, but paronite gaskets with a Mayevsky tap are not recommended. Some people prefer to additionally use a linen winding or fum tape to strengthen the thread, but this is not necessary. Tip - during installation, you need to direct the outlet slightly downward. So it will be more convenient to collect water that will flow out of the radiator at the end of air bleeding.
For the installation of Maevsky cranes, the highest point of the system is selected, since the air rises. In this case, of course, it is necessary to take into account the features of the heating system of a particular house or apartment.
With a vertical heating circuit, air vents should be installed on all radiators on the upper floor, which have a lower flow in the return pipe. It is also necessary to provide Maevsky cranes with all devices, the supply of which (or part of it) to the riser is located below the upper connection axis, since in this case the removal of air from the system will naturally be difficult.
The diagram shows the principle of installing a Maevsky crane with a vertical and horizontal heating system. The crane is necessary in places of accumulation of air
With a horizontal heating system, air vent valves are installed on all heating devices: batteries, collectors, etc. The underfloor heating system does not always need air exhaust, 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 lower connection, a special hole is even provided for this. But the heated towel rails with side connection will have to be slightly modified. A metal tee with a thread of a suitable diameter is mounted on the supply eyeliner. In this case, the outlet of the vent valve must be turned away from the wall.
It is always recommended to install the Mayevsky crane on the heated towel rail. One or two cranes should be installed depending on the model.
To understand whether to install an air vent in a particular place, you just need to imagine the movement of air in the system. If it is clear that air can freely move further through the system, a valve is not needed. If air cannot leave the system naturally, a special device will be needed.
