Removal of air from the system: how is the descent airlock

If there are problems in the operation of the heating system, they are usually found at the beginning of the heating season.

Many problems such as uneven heating of the radiator or excessive noise, eliminates the simple action - venting the heating system.

The dangerous air pockets?

air from entering the water heating system - a very common phenomenon. And respond to it immediately follows. Although a certain amount of air in the system may not seem dangerous, it often causes a more serious problem.

Sometimes zavozdushennost radiator or pipe reveals breakage or flaws in the assembly of the heating system.

The presence of air pockets usually manifested in the form of uneven warming of the system components, such as radiators.

If the device is filled with partially-cooled, its operation is hardly effective, since the room loses part of the heat energy, i.e. not warming up.

If the upper part of the heating radiator remains cold and warming up only the bottom most likely zavozdusheno device then vent

If the air is accumulated in the pipes, it prevents normal movement of coolant. As a result, the heating system may be accompanied by quite strong and unpleasant noise.

Sometimes part of the system begins to vibrate. The presence of air in the circuit causes the activation of various chemical processes, for example, may cause decomposition of calcium bicarbonate and magnesium compounds.

This leads to the formation of carbonic acid, which violates the acid-alkaline balance of the coolant.

Increased acidity enhances the corrosion of the elements of the heating system, which can lead to a marked reduction in their lifetime.

Furthermore, chemical processes under high temperature to cause deposition on the walls of the pipes and radiators limestone precipitation, creating a dense coating.

As a result, the lumen of the tube decreases, the characteristics of the heating system vary, it works less efficiently. A large amount of lime can fully score the pipe, they have to be cleaned or even replaced.

Air in the independent heating system may indicate processes that contribute to the appearance of sludge and clogging of pipes heating circuit

If included in the heating circuit pump, air in the system may adversely affect on its operation. Bearings of this device designed for permanent residence in the aqueous medium.

If the pump gets air bearings will run in dry run mode, which will cause it to overheat and malfunction.

The causes of excessive air

Causes of a lot of air to completely avoid this phenomenon is difficult. Still, should explore the factors that could cause the air pockets are formed in the heating system in order to minimize their impact on the system.

Most often air enters the system:

• if the heating was originally installed improperly;
• non-compliance with the rules of filling water heating circuit;
• if leakproof connection of the individual elements of the system;
• when the system is missing or incorrect use of the air outlet;
• After repair work;
• in recovering lost coolant volume with cold water.

Improper installation of the heating system leads to its airing in cases where pipes are laid with wrong slant, form loops, etc. It is best to keep track of such areas is still at the design stage of the Autonomous heating.

Filling the water circuit should be carried out according to the principle: the greater the volume of coolant, the lower the speed of its arrival in the system.

If water is supplied too quickly, in certain areas it can be spontaneous one water seal, preventing the natural process of displacement of air from the circuit.

The junctions of pipes and radiators leaks often arise. Sometimes the crack is so small that its corollary, the water evaporates almost immediately.

The hole goes unnoticed, and gradually penetrate therethrough the air which replaces the lost volume of water.

A small gap, through which water flows, may cause air leakage in the heating circuit and the entrapment of air

As one way or another circuit may still be zavozdushennym, the design of heating It should provide for the installation of special devices for venting from the system heating.

If these air vents are available, but do not give the desired effect, maybe some of them are broken and need to be replaced.

It also happens that the air exhaust device ineffective due to their incorrect installation or insufficient amount. Inevitably air from entering the system after repairs.

In this case, necessarily have to carry out bleeding of activities.

air dissolved in the water enters the heating system during the filling contour. When heating it is released in the form of small bubbles, which is formed from the airlock

If the volume of the coolant is lost, it is necessary to fill. Fresh water, as opposed to one that is already stored in the system contains an amount of air dissolved in it. When heated, it stands out in the form of small bubbles and accumulates, forming a plug.

If the system dolili fresh coolant does not hurt to make sure after a while, she never zavozdushena.

Methods for removing air from the system

So, to avoid the airing of the heating system, it is necessary to properly design and install a timely manner to clean and fill the coolant without undue haste.

Even so, one or more air pockets may still appear in the system. What to do in this case? The procedure depends on the particular design of the heating system.

Method # 1 - the correct installation of the heating system

In circuits with natural circulation of the coolant at the upper wiring venting through outdoor expansion tank. When installing such a system flow line is set so that it rises vertically to the tank.

Volume, providing space for expansion of the coolant during heating, put at the highest point of the system, and this provides a natural progression of fluid by the heating circuit.

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Bleed screw - a small device with a turning mechanism, opening / closing a channel for removing air accumulated in the battery

Many models now produce aluminum, bi-metal, cast iron radiators originally equipped with bleed screw

Obsolete cast-iron batteries are also equipped with valves for fighting air, but after a few cycles of staining such a valve has been difficult or impossible to open

Manual air radiators mounted on the upper floors in vertical wiring on each radiator in pumping systems with horizontal

A device for exhaust air is mounted on the radiator towel, connected to the heating circuits

The air required for bleed position bleed screw is turning the key or screwdriver

Majewski air through the valve removed as long as the water from the heating unit does not start to follow the water

After the withdrawal of excess air from the heating valve is rotated in the opposite direction to close the passage for discharging air

Manual air vent for radiators

Components of the bimetallic device

Manual air valve predecessor

Majewski crane in use

Installing the air vent on the heated towel rail

Key management deaerator

Leaking water serves as a signal to terminate bleed

Mechanical air vent is closed

Return line and must be installed with slope, promotes natural movement of the coolant flow.

If the system is correctly installed, the air caught inside the loop will gradually be replaced by hot water up and leave freely through the conduit communicating with the atmosphere expander surface tank.

Method # 2 - Installation of air turbulator

Scheme removal of air from the forced circulation circuit differs from the previous type. At the top of such a system is installed outdoor expansion tank, and a closed return line prior to entering the boiler.

In such a system, the feed line must not be sloped, as moving stimulated coolant pump and to reset the device uses air pockets different.

To remove air from the system are special automatic air vent installed in the uppermost points of the system and on the corners of the pipeline.

To remove the plugs from the radiators used cranes Majewski. In the same way the air is removed from the heating zone of a natural circulation, but lower wiring tubes.

With proper installation procedure for removing unwanted air from the system is very simple, it is reduced to opening corresponding valves and their closing after formed will leave air in the heating system traffic jams.

Automatic air do not need to open. They are triggered by a change in pressure.

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Automatic air bleeds air from the system without the participation of its owners

Inside the automatic device is placed a float which, when the accumulation of air in the housing is displaced and opens the valve to output airlock

As air rushes at boiling water up the air deflecting devices must be equipped with all of the highest point of the heating systems or portions thereof

Automatic air vents placed where there is a possibility of air congestion. In systems with the top distributing them equipped with risers

The heating circuits with the lower wiring circuit device often put in place on the radiator valves Majewski

Float type air vents mounted on the collectors for hot coolant and for the return

In complex circuits heating, collected from several rotations pipeline automatic air try to equip each turn to avoid the formation of air pockets

In closed systems, regardless of their type and complexity of wiring buildings air vent installed on a mandatory basis since includes a security group

Automatic air vent type

Float valve operation control principle

Location of the float device in the highest point of the system

Installation on the main pipeline

Automatic air in the circuits with the lower wiring

Output air from the reservoir

Location in complicated contours

Air vent in the security group

Heating gated schemes complement the automatic air vent on a mandatory basis.

They are placed across the circuit at certain points, allowing air to remove the stopper from the contour locally, without waiting until the air moves to the upper point of the system. This scheme is called multi-stage deaeration system.

The idea is to allow the air exhaust for each of the heating circuit. Typically, each radiator is provided with an air exhaust device with manual control, for example, bleed screw.

If the hot radiator from below while the upper part remains cold, then it is necessary to remove trapped air.

If even after the air bleeding through the bleed screw radiator warms unevenly, the device should be removed and cleaned or replaced the new

This will require a key or a screwdriver, and a container for collecting water and a rag for the floor. Using bleed screw tool is opened and the container is substituted under it. Air exits with typical hiss.

When the plug is removed from the bleed screw water flows. Now you can close the valve. In most cases, this is a simple procedure allows you to restore a uniform distribution of coolant around the radiator.

The automatic air vent are horizontal and vertical type. They are installed in places where the probability of an airlock is greatest. These may be portions where the heating tube makes a turn, a loop, etc.

Zavozdushennost heating system is more common in the upper floors of the building, so there is a plant for air exhaust devices should be given special attention.

In this scheme are shown places installation devices for air exhaust from the heating system: automatic bleed cock and Majewski

When using the automatic air vent is important to monitor the level of pressure in the system. In addition, such devices have increased sensitivity to contamination.

To extend the life of the automatic air vent should be installed good filters, as well as to regularly flush the heating circuit.

Automatic device for removing air required for installation of heating systems of the closed type. Their installation allows you to remove air pockets quickly and without human intervention

To determine the place where the accumulated air, radiators and pipe to start just probed. Where the heating temperature is much lower, and is generally an air pocket.

Another way to identify zavozdushennoe place - tapping circuit. Use a small piece of metal, which is applied neat strokes. In places where air build sound is more sonorous.

Method # 3 - strong heating of the heat carrier

Sometimes natural remove excess air from the heating circuit to heat the heat carrier sufficiently strongly. High temperature stimulates the air separation process and its progress through the system. It allowed heating water in the heating system to 100 degrees.

In this diagram represented separator device for air. This device allows you to remove from the heating circuit, not only the air but also pollution

If the formation of air pockets in the system occurs over and over again, you should explore all joints for leaks.

Near the site of the entrapment of air almost certainly found a small crack from which water flows seamlessly and in that leaks air bubbles. Incorporation of such a gap or crack will solve the problem.

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Instead bleed screw and the float venting the heating system can be equipped with air separator operating based on Henry's law

In this arrangement, air bubbles are separated from the water, accumulated and outputted to the atmosphere

In order to extend the operational life of the separator, device manufacturers recommend embed it in front of the pump

If there is a possibility of contamination of coolant sludge, the network device is installed, which acts as a separator and the dirt separator

Air Separator pipe section

Deposition device in the heating system

optimal location

Symbiosis separator and the dirt separator

The most vulnerable to the appearance of air pockets deemed aluminum radiators. Interaction hot coolant from the device causes the development of material corrosion processes which are accompanied by evolution of gaseous substances.

If zavozdushennost such radiator is observed over and over again, it makes sense to replace it with a more modern instrument with an internal anti-corrosion coating.

Filling the heating circuit coolant

To the heating system to operate properly, it should be cleaned, and then re-filled with water. Often, at this stage in the circuit is leaking air.

This is due to the improper actions during the filling loop. In particular, air may be captured by too rapid a water stream as mentioned earlier.

Driving an open heating circuit expansion tank gives an idea on how to fill a coolant system after flushing

Furthermore, correct filling circuit also contributes to more rapid removal of the portion of air masses, which are dissolved in the coolant.

To begin useful to consider an example of filling the open heating system, at the uppermost point of which the expansion tank is located.

Filling such a coolant circuit follows, beginning with the lowermost portion thereof. For these purposes, the system is mounted in the bottom stopcock through which the supply of tap water to the system.

In a properly arranged the expansion tank has a special nozzle, which protects it from overflowing.

This pipe should be put on a hose long enough to end his second was placed on the site and was out of the house. Before you start filling the system should take care of the boiler.

It at that time, it is recommended to turn off the system to not work protection modules of this unit.

After these preparations are made, you can start filling loop. Crane for the lower part of the circuit through which the tap water is opened so that the water fills the tube very slowly.

Recommended flow rates during filling should be approximately three times less than the maximum possible. This means that the crane should not turn away completely, but only one-third of the lumen tube

Slow filling continues until then, until the water flows through the overflow hose, bred out. After that, the tap should be closed. We must now go through the entire system and on each radiator to open the bleed screw to release the air.

You can then connect back to the boiler system. These valves are also recommended to open very slowly. During filling of the coolant can hear the hiss of the boiler, which produces a protective air relief valve.

This is normal. After that, the system must again pour water all in the same slow pace. The expansion tank must be about 60-70%.

After that, you must check the heating system. The boiler is switched on and the heating system is heated. Then radiators and pipe examined to identify places where heating is missing or insufficient.

Insufficient heating indicates the presence of air in the radiator, you need to hold it through the bleed valves Majewski again.

If the procedure of filling the heating circuit coolant is successful, do not relax.

For at least another week, the system should be carefully monitored, to monitor the water level in the expansion tank and check the status of pipes and radiators. This will allow us to solve these issues.

Similarly, the coolant filling is carried gated systems. The water in the system should also apply to low speed through a special valve.

Run filling the heating system of closed type with working fluid (coolant) can be their own. It is important for this gauge arm

But in such systems important point is to control the pressure. When it reaches the level of two bars, the water should be turned off and pull air from the radiator through all Majewski taps.

Thus the system pressure begins to drop. It is necessary to gradually add coolant to the circuit to maintain the pressure at the level of the two bars.

Perform both of these operations alone is difficult. Therefore, we recommend filling the closed circuit to perform with the assistant. Until one pulls air from the radiator, his partner controls the level of pressure in the system and immediately corrects it.

Working together will increase the quality of this type of work and reduce their time.

Useful videos on the topic

Here is the process of removing excess air from the radiator via Majewski crane:

For information on how to bleed air from the heating circuit, which does not go through the air vent, narrates the following video:

Trapped air in the heating system, reducing its efficiency and may cause damage to certain knots. To cope with this problem, it should be initially correctly perform the heating installation or fix existing flaws. In addition, you must install a vent pipe and observe the rules of operation of heating systems.