the main / All Plumbing / heating / How does Majewski faucet and how to use it

How does Majewski faucet and how to use it

Bleed screw - this device, which applies for the release of the heating system of the air mass, which are harmful to heat transfer. Open and close it can use a screwdriver or a special key. Cranes Maevskogo, the principle of which is simple to genius, It applied in practice for more than 80 years old. And precisely because of its simplicity earned him the trust of consumers.

According to state standards, This device is referred to as the radiator air needle valve. A crane Majewski - a popular name.

The composition and working principle of the crane

Majewski crane device does not allow to open it to everyone, at any time. This is done in reasonable order, because, if you open it you can easily and conveniently, all will be drained from the battery (especially those living in areas, deprived of hot water), as this will cause heat loss. Besides, this design helps to avoid children's pranks.

Majewski crane structure consists of:

  • housing;
  • screw cone shaped.

Bleed screw with a special pen
Bleed screw with a special pen. The figure shows the drain hole.

Both parts are connected tightly. They are made mostly of brass. This metal does not corrode, allowing the device to serve as a long. Bleeding the air mass occurs through a hole in the side of vessel diameter 2 mm. When the valve is opened, air exits.


obviously, because of the extremely small diameter of the hole for the air outlet, it is a weak point in the crane, because it can clog, but clearing it made easy. To do this, open the valve and release the openings from clogging by using a conventional needle.

Majewski valves can be opened in different ways - with a special key, screwdriver, wrench or all of these at the same time. There is also a crane, which open handle without special tools.

Maevskogo tap into otvёrtku or key
Maevskogo tap into otvёrtku or key vmontirovannыy in radiator

There are more automatic bleed screw and the principle of their operation is similar. Only automatically open itself, when the air appears in the coolant. The device responds by separating the inside of it with a float made of plastic. When the compartment is filled with air, float via spring structure opens the air outlet. When the air is not, the float closes the valve.

The automatic version is suitable in cases, When heating is installed in inaccessible places, or, when you want to release the coolant from the air often.

According to the laws of physics, air in the pipes tends up. The installation bleed screw must be made on the upper floors and on the top of the radiator. Otherwise, the effect of it will not.

Automatic bleed screw
Two provisions of the automatic crane Majewski - open and closed.

Releasing air from the heating system

Simplicity of design implies ease of operation, but before, how to use the bleed screw, you need to take care of the cleanliness of the procedure - so as not to flood the neighbors and do not spoil the floor, you need to prepare a bucket.


To deflate the air from the radiator needed:

  • A bucket to put under the drain plug, So, that in case of leakage of water, it does not hit the floor.
  • Using a special key, screwdriver or wrench gacheny, turn the valve counter-clockwise by one turn.
  • After that hiss should appear, which indicates the outlet of the pipe.
  • Then go waterdrops. Once the water starts flowing stream, Valve should be tighten, turning it clockwise.

It must be remembered, that the later close the bleed screw, the more water will flow out from the heating system. This threatens flooding and poor efficiency of the coolant. Therefore, in the derivation of air pipes, should all the time be near.


Tips for operating the crane Majewski

  • If the heating system has accumulated a lot of air, the crane can not turn to accelerate the process 1, and on 1,5-2 turnover.

If you unscrew the tapered portion is completely, then it will then be difficult to insert in place because of the water pressure. So do not overdo it.

  • If the heating system operates with the pump, which turns the heat transfer fluid is forced through pipes, before, how to use the bleed screw, you need to disable it. Start procedure can be only through the minutes 5 thereafter. Otherwise not be able to remove the air masses effectively.
  • Automatic bleed screw should not be installed in a contaminated coolant. It will often become clogged and have to be cleaned.
  • The central heating should be used bleed screw OMEC domestic or MS-140. They are able to resist the force to congestion 15 atmospheres, which are common in such systems,. And they can be used on old cast iron radiators.


Share with your friends to vote record

Rate post:
1 Звезда2 Звезды3 Звезды4 Звезды5 Звезд (1 assessments, the average: 5.00 of 5)
Do you want to place the information in this or any other article - contact, discuss.

One comment on the record "How does Majewski faucet and how to use it

  1. During the repair had to change one of the heating radiator. set aluminum. Included with it was the crane Majewski. Since our apartment on the top floor of the house, every season is to lower the air with battery. Majewski crane in this case simply does not replace. On older iron batteries falls down through the air-wrench g. When the air end water splashes in all directions. Aluminum battery water is discharged directly into the stream of neat bucket, the substituted for the battery. By the next season the plans to put the bleed screw on the battery and forget about the divorce rusty on the slopes and the curtain.

Share your experience in the repair

Your email address will not be published. Required fields are marked *

4 × 4 =