How to steal air from a heating system correctly

Being homeowners, we want our homes to be cozy and warm, especially in the winter. Making sure our heating systems are operating at peak efficiency is one way to maintain the ideal indoor climate. Occasionally, this calls for adjusting the system to improve its functionality. One method that can help achieve this is "stealing air" from a heating system, which basically means modifying airflow to balance heat distribution.

By using this technique, airflow is redirected from places that don’t need it as much to areas that do. It’s a workable fix for inconsistent heating in a home. Care must be taken during this process, though, to prevent the system from becoming out of balance or creating long-term problems. By doing this correctly, you can reduce your energy expenses and raise the comfort level of your house.

It’s crucial to comprehend the fundamentals of your heating system before making any adjustments. Various methods may be needed for different systems, such as forced air, radiators, or underfloor heating. With this information at your disposal, you can make wise choices that will prolong the life and maximize the effectiveness of your heating system. Let’s look at how to properly modify your heating system’s airflow so that every room in your house stays toasty during the winter.

How to competently lower the air from the heating radiator?

The heating system needs to be properly set up before it can be turned on. This issue is not likely to affect someone who lives in a high-rise building in a city. After all, carrying out such a procedure is the responsibility of ZhEK employees. However, private sector owners bear the brunt of the heat alone. Nevertheless, batteries can still warm up slowly and, in certain cases, even become cold during the heating season. Most likely, the system is ascending.

Whatever the situation, you should be aware of how to reduce the airflow from the heating radiator to prevent accidents involving malfunctioning machinery. You can learn more about the causes of air cork, how they affect the heating device’s functionality, and how to remove them by reading the article.

Than the air traffic jam in the radiator is dangerous?

Nothing positive will come from the battery if it appears in the battery. Extra air gets in the way of the system’s regular operation. additionally have the potential to produce corrosion on the radiator’s walls.

If the circuit has a circulation pump installed. Its work may be violated by air cork. The pump unit’s shaft’s sliding bearings are continuously submerged in water when the system is functioning properly. Additionally, "dry friction" has an adverse effect on sliding rings and has the potential to disable the shaft when there is a gap. For this reason, it’s critical to understand how to remove air from the home’s heating system. Prompt action will help shield the network of heat supply from damage.

How to understand that the battery has an air traffic jam?

Prior to releasing the air from the heating system, you must ascertain the cause of the air traffic jam in the radiator and learn how to recognize it in the circuit. The most common cause of excess air accumulation in systems is incorrect water filling. It’s possible that mistakes made during installation are to blame. Low coolant quality, low circuit pressure, and the presence of dissolved oxygen can all be significant factors.

Air cork can happen in the following situations:

  1. The components of the system are connected loosely. As a result, the air from the outside is sucked in a battery.
  2. There is no air vent or it is available, but it works incorrectly.
  3. Repair work was carried out to replace locking mechanisms, risers, heating devices, during which air penetrates the system.

The following symptoms could point to the accumulation of excess air in the system: the battery making hissing and gurgling noises; the heating becoming uneven and of lower quality; and the radiator possibly being cold in areas where there is an air presence.

These kinds of circumstances are not unusual. Undoubtedly, all owners of private homes or apartments have encountered a similar issue. As a result, it is crucial to learn how to extract air from the home’s heating system, and doing so is quite simple to accomplish by hand. It should be mentioned that batteries installed on the upper floors of a home are typically where air cork forms.

Crucial! A poor-quality radiator can occasionally be the cause of the cork’s formation.

In this instance, no matter how much air is removed, it will re-form. The material used to make the battery contributes to the formation of gases, which is the reason behind this. Purchasing a new radiator is the only way to get out of this predicament. It is therefore preferable to buy heating devices from legitimate manufacturers right away.

How to remove excess air from the battery?

Prior to lowering the heating system’s air pressure, make sure you are familiar with its features and have all the equipment and supplies you’ll need. Take a closer look at the process of removing air from the heating system. To accomplish this task, you will require a unique key that will enable you to open the radiator’s air valve.

The ideal key is the radiator key. Any business store sells it. If it’s a modern battery, all you need is a basic screwdriver. The container that the coolant will combine with must be ready. Additionally, keep a few rags on hand in case something unexpected happens.

The steps to correctly remove air from the heating system are listed in the algorithm below:

  • Inspect the battery and find a small valve (or Maevsky crane, as it is most often called). Install it in the upper part of the radiator. Sometimes there are several such devices. But often bypassed by one valve.
  • Unscrew the crane until the anger is heard. You need to unscrew carefully, smoothly.
  • Put a container under the valve.
  • You need to wait until the entire accumulated air goes outside. Когда вода будет выходить тонкой струйкой и прекратит пузыриться, значит, воздух из системы вышел. Some experts advise to drain about 2-3 buckets of water after water starts to run without gases. This is done for reinsurance so that such operations do not have to perform again.
  • Twist the tap back.

Automated air vents for heating systems, which draw extra air on their own, are frequently utilized in addition to Maevsky cranes. These automated systems are dependable and small in size. However, you also need to exercise extreme caution. The valve operates unsupervised, after all. Additionally, even the smallest process infraction can result in riser or attic flooding.

Some nuances

There are instances where the masters neglect to install specific valves for the descent of excess air when installing the heat supply system. In this instance, think about how to discharge air from the heating battery. You’ll need a divorce or gas key in order to work. You have to unscrew the plug with it. You must proceed very cautiously. Occasionally, the plug refuses to unscrew. This typically occurs when a cast-iron battery is used. In this instance, the thread needs to be lubricated with a specific substance, and the attempt must be repeated later.

The sequence of steps is the same as with a traditional crane once the plug is unscrewed. When a worm starts to grow on a surface, it is important not to disturb it by rubbing it against a plant or a person. By doing this, leaks will be prevented and the connection will be tightened.

An expansion tank must be used for the water descent in a private home’s heating system if air has accumulated inside.

This container is situated at the system’s highest point at all times. You must wait a short while after the water is lowered before unscrewing the expansion tank tap. Usually, the cork pops out on its own when the battery temperature rises. Should such actions have been taken without authorization, the water should be brought to a boil within the circuit. The cork will undoubtedly come out in this instance.

How often you need to lower the air?

By learning how to take air out of the heating system, you can prevent and fix a lot of issues. However, how frequently should this process be done to avoid? This should usually be done at the start of the heating season. It’s sufficient to do it twice—once for verification and once for control. Naturally, a high number of descents may occur if the system is flawed or has flaws.

If the apartment has aluminum radiators installed. then creating a water descent is required prior to initiating the system. This will contribute to the battery’s lifespan being extended multiple times.

Preventive measures

It goes without saying that knowing how to blow the heating battery is crucial. However, it is preferable for the system of accumulation to occur as infrequently as feasible. Installing the air vent and alerting others to the situation is preferable.

Currently, heating systems have two options for air intakes: float (or automated) and manual (represented by Maevsky’s crane). Any of the aforementioned varieties can be installed in different locations where there is a chance that a gummer may appear. The Maevsky crane has a conventional configuration. An auto-seizure may perform directly or angularly.

Every battery needs to have an air vent installed in order to prevent you from scratching your head over how to destroy the heating system.

Manual type of air vent

Typically, a manual air dispenser is installed on the radiator’s end side. They make it easy for you to suffer from too much air. Simply possess a unique key. These devices have low performance. For this reason, the heating system’s equivalent of an air collector is installed exclusively for domestic use.

Automatic type of air vent

Regarding the automatic air vents, they operate on their own. Unscrew; nothing will open. The gadget functions entirely on its own. Install them rigidly either horizontally or vertically. However, I must admit that there is one disadvantage to such a valve for lowering air from the heating system: it is extremely sensitive to different types of pollution. As a result, you’ll also need to install the filter in order to clean the gadget from mechanical pollution.

Crucial! If air appears within the heating system, you ought to investigate the reason behind this circumstance. particularly if there had never been any issues of this kind. It is crucial to take all necessary precautions to ensure that the air cork does not reappear in addition to simply removing it. As a result, you must verify that the gadget is tight. Maybe there’s a place where you should tighten the bolts, replace the nuts, or improve the joints. Additionally, it’s possible that the air vent is misinstalled or that the heating automatic airplane separator is broken.

In conclusion, we can state that the issue of systemic bullying is highly pertinent. Both private homes and urban high-rise buildings may experience it. The formation of excess air can be caused by a variety of factors. To ensure that such circumstances do not arise in the future, it is crucial to identify the actual cause and possess the necessary skills to release air from the heating radiator.

The installation of specialized air vents and the proper and efficient operation of radiators are crucial. Installing such a device will allow the homeowner or apartment owner to save time and money, eliminate the issue of air traffic jams arising, and prolong the life of the heat supply system as a whole.

Eliminate the air plug from the heating system

Air traffic congestion in the pipeline and heating radiators interfere with the system’s regular operation and lower its heat output. Air must be removed from the heating system in order to remedy the issue. If you properly design and install an autonomous system that allows for the installation of air vents in all trouble areas, you will have to use emergency measures noticeably less frequently.

Getting the heating system ready

Reasons for the formation of air traffic jams

Although the sealed sealed closed heating system is completed, air bubbles may still exist. Where does the gas that powers radiators and pipes come from?

The following causes of air in the heating system include:

  1. The coolant is water supply, which has not undergone special preparation – when heated, the air dissolved in water begins to stand out, and traffic jams are formed from small bubbles.
  2. The tightness of the system is disturbed, and the air is gradually sucked through loose compounds.
  3. During the repair work, part of the circuit was disconnected by the cutting cranes, a replacement or cleaning of any elements was carried out, and then the coolant was again supplied to the renovated circuit.
  4. The pipeline is laid with violations of the standards – a small angle of pipe slope and improper installation of extensions prevents the gas bubbles from getting into special devices – air vents. As a result, gas accumulates in problem areas and interferes with normal circulation of the coolant.
  5. If the heating system of a private house is filled very quickly (or when the coolant is supplied at the lower point), the liquid is not able to completely supplant the air from the compounds of the pipeline and radiators.
  6. The air vents are absent or incorrectly located. Also, the cause of the incorrect operation of the device for eating air is its pollution by mechanical inclusions in an unstopted coolant.

The hand crane Maevsky used on the radiator

It’s important to think about gas formation in aluminum radiators separately. Hydrogen is released when the metal comes into contact with a slightly alkaline coolant; this gas builds up at the heating device’s upper point. Over time, the gas cork in a radiator without an air tower will obstruct the coolant’s free passage through the internal channels of the heating device.

Signs and consequences of the system of system

If the boiler unit operates as intended, the coolant temperature at the supply is within normal limits, and the battery is unable to adequately heat the room, make sure there is air in the heating system. Radiator air traffic jams are a common occurrence; their presence is indicated by the device’s uneven heating when the upper portion stays cold. The battery’s initial modest reduction in heat transfer is due to its dedication; however, if the issue is not resolved quickly, the gas buildup will obstruct the coolant’s path and prevent the room from heating up to its maximum potential.

Due to the channel’s narrowing caused by air bubbles, the coolant cannot flow freely, which causes certain sound effects to occur. Seething, bubbling, and noise in the pipes are indications that a cork is forming. In more challenging situations, the pipes’ vibration is added.

Taking the heating system apart

The coolant becomes a water-air mixture due to tiny air bubbles that are actively released from it but have not yet formed a plug. A circulation pump that is not designed to pump gas should not be used. The shaft of the pump unit, which ought to be submerged in the liquid medium, has sliding bearings fitted on it. Because of the effect of dry friction, high coolant air content causes elements to wear out before their time.

If the heating system’s air is not shaded, an excess of it in the coolant may cause the circulation pump to malfunction or stop. For solid-fuel boilers without automation, this poses a risk because the cooled coolant will no longer enter the boiler’s water shirt when the circulation stops. If a security group is ineffective, the overheating and boiling of fluids in a closed space could result in an explosion.

You can deal with air lenses in radiators made of materials prone to corrosion and overgrowth if you know how to remove air from the heating system. Salts of calcium and magnesium that are dissolved in water break down due to the presence of carbon dioxide and oxygen in the air. Carbon dioxide is released as the reaction continues. Bicarbonate compounds produce a layer of lime plaque when exposed to high temperatures, and carbon dioxide accelerated the corrosive process on metal surfaces. The battery depletes more quickly as a result.

One of the factors contributing to the radiator’s failure is accumulated dirt in the heating system.

Check for air traffic jams before turning on the house’s heating system after summer vacation to avoid any unpleasant surprises. Should it be committed, act promptly to solve the issue.

Heating system without air traffic jams

It is essential that the air in a personal heating system escapes problem areas rather than building up there.

  • correctly design and mount the pipeline, correctly install radiators;
  • use automatic and manual air vents.

Think about the best ways to remove air from the heating system using upper wiring and natural circulation. It’s crucial to arrange the pipeline at an inclination that allows air bubbles to freely travel upward at the circuit’s highest point without building up on the bends and gentle areas. An open-type expansion tank, which allows air bubbles to enter the atmosphere, should be positioned at the highest point of the system.

Utilizing an automated airier to remove air from the heating system

A different principle is used to puff air out of the system with a forced coolant movement or gravitational system with lower wiring. The system’s fluid drainage is made simpler by mounting the reverse pipelines beneath the slope, and air is emptied as it builds up through automatic valves positioned at the top of each contour.

The Maevsky manual cranes are part of the system in addition to the automatic air vents. On heating radiators, these air vents are installed to the upper pipe on the other side of the pipe that supplies heated coolant. It is advised to install the heating device at a slight angle to ensure that air enters the valve and does not build up in the radiator’s upper collector. When necessary, air discharge is done manually.

How to find an air traffic jam?

Ideally, the system can handle felining on its own because of automated valves that draw air through. Once a separate heating device or a malfunctioning portion of the circuit has been identified, the location of the air accumulation must be determined.

If the top of the radiator feels colder than the bottom, coolant is not getting to that area. Open the valve crane mounted on cast-iron batteries or the Maevsky crane mounted on a steel, aluminum, or bimetallic radiator to let out air.

How to find the battery’s air traffic jam

The location of feloning can be identified by sound; in typical circumstances, coolant flows almost silently; extraneous gurgling and overflow noises are caused by stream obstructions.

Light blows are used to tap metal pipes and heating devices; in areas where air has accumulated, the sound is audibly more noticeable.

Getting rid of the air traffic jam

The inability to extract air from the batteries does not occur when radiators have manual air vents. The Maevsky crane rod is gently loosened with a screwdriver or standard key, and a suitable container (a half-liter glass jar will do) is placed beneath the drain hole. A thin stream of coolant flows as the air descends from the heating system through a manual air vent, producing a hiss and whistle before spraying out. The Maevsky Crane ought to be closed at this point.

Note: The issue might disappear if the battery keeps heating up poorly following fragmentation. Here, the heating element is taken apart and cleaned. Check for air traffic jams in the system after the radiator is installed.

They arrive as follows in order to clear the air traffic from the heating system if it builds up away from the air vent (manual or automatic):

  1. Open the air valve closest to the air bubble.
  2. They begin to subtract the system a little by the coolant so that the fluid due to an increase in the volume displaces the air bubble towards the open air vent.

An automatic air duct connected at an angle

What should be done in challenging situations where the plug does not stop the volume addition? In this case, it is essential to apply pressure in addition to adding more coolant, which will raise the liquid’s temperature to critical levels. When air is released through an automatic valve, there is a spray that can burn you if you are not very careful.

Crucial! Cut the tee here and install the automatic valve if the cork is consistently formed on this section of the pipeline.


The quality and dependability of automatic air vents should be carefully considered when buying heating equipment; these vents must function correctly to remove air plugs only after the coolant has drained and filled the contour. Lowering the air in the heating system won’t cause any additional problems if you know how to do it.

How to lower air from batteries and heating pipes

Partially cool radiators or heated sections of water are signs that an air traffic jam is forming in the heating system. There may occasionally be a distinct murmur in pipes and batteries that lets you locate the accumulated air roughly. I’m curious about two things: how to get rid of it and stop problems like this from happening again. In order to provide comprehensive answers, take into account the causes of the dummy of heating devices in individual homes before we explain how to get rid of air bubbles in various scenarios.

Where does the air come from in the system

Experience demonstrates that it is impossible to completely shut off a water heating network from the outside world. Air enters the coolant through a variety of openings and progressively gathers in specific locations, such as the top corners of the batteries, the curves of the highways, and the highest points. By the way, the latter needs to have the air vents (automatic descent valves) in the picture installed.

Different Automatic Aeronics Varieties

The following are the ways that air enters the heating system:

  1. Together with water. It is no secret that most homeowners replenish the lack of coolant directly from the water supply. And from there comes water saturated with dissolved oxygen.
  2. As a result of chemical reactions. Again, the water is not properly desecrated with metal and aluminum alloy of radiators, which is why oxygen is released.
  3. The private network of a private house was originally designed or mounted with errors – there are no slopes and loops that were facing up and not equipped with automatic valves are made. It is difficult to expel air clusters from such places even at the stage of refueling by the coolant.
  4. A small oxygen fraction penetrates through the walls of plastic pipes, regardless of a special layer (oxygen barrier).
  5. As a result of repair with disassembly of pipeline reinforcement and partial or full water descent.
  6. When microcracks appear in the rubber membrane of the expansion tank .

The gas is combined with water when the membrane cracks.

Because well and shallow well water is saturated with active calcium and magnesium salts, chemical reactions are likely to occur.

Additionally, a scenario frequently occurs when air enters the closed heating system after an extended period of inactivity during the off-season. It’s very easy to lower; all you have to do is add a few liters of water. In open-type systems, stopping the boiler and circulation pump, waiting a few days, and then restarting the heating will have a comparable effect. The liquid is compressed during cooling, which allows air to enter the roadway.

Regarding apartment building centralized heat supply systems, air only enters when coolant is added or when the network is first filled with air at the start of the heating season. Read on for advice on how to handle it.

An instance from real life. Every day, air traffic jams had to be cleared from the open heating system because of the completely clogged mud. The functioning pump generated a vacuum, which allowed even the smallest leak to draw oxygen into pipelines.

The heating device is displayed, and this is where the air bubble typically appears later.

When discussing how to properly bleed air from a heating system, it’s crucial to emphasize the importance of removing trapped air from radiators and pipes to ensure efficient heating throughout your home. Air pockets in a heating system can lead to uneven heating, noisy operation, and increased energy consumption. The process typically involves using a bleed key or screwdriver to open the small valve found at the top of each radiator, allowing the trapped air to escape until water begins to flow out, indicating that the air has been expelled and the system can operate at its optimal level. Regularly bleeding your heating system, especially before the start of the heating season, can help maintain its efficiency, reduce energy costs, and extend the system"s overall lifespan.

Remove the air plug without draining water

You most likely already know how to remove air from the heating system using conventional techniques. After finding a non-heated radiator, you must use a screwdriver to open the Maevsky crane and let the air bubble out. There are alternative methods you can try to remove old batteries if they are installed somewhere without such a valve:

  1. The so -called pumping of the pipeline network is used in apartments of multi -storey buildings, provided that a crane is laid for a radiator to discharge water. Connect a hose to it aimed at the sewer, open the valve to the maximum and perform the drain, until the flow moving at high speed will captivate the air traffic jam.
  2. In a private house, Soviet steel batteries can be broken with a self -cutting screw. Wrap it at the base of the fum tone and screw with a screwdriver into the wall of the heating device (closer to the top). Then turn the screw for a couple of revolutions with a screwdriver, release the air and tighten it until it stops. In the summer, cut the crane of Maevsky in this place.
  3. Air removal from the cast -iron batteries of a summer house not equipped with aerialists can be performed in two ways: a complete re -refusing of the system or by increasing pressure (up to 2 bar) with simultaneous heating. It is not recommended to twist the side plugs “on the go”, then it will be difficult to pack them.
  4. Weak circulation and heat transfer can be a result of air accumulation in the network pump body. Unscrew the large screw installed in the end of the unit for a couple of revolutions. When drops of water protrude from under the rubber ring, tighten it back.

Suggestions. Lower the airflow in each radiator to avoid air traffic jams while the system is operating. Weld the boss with the necessary diameter hole on top if the thickness of the metal wall prevents you from cutting three or four turns of thread. A side steel plug covers the valve in cast-iron "accordions."

For improperly designed highways with loops facing or downward (for example, to bypass doors and other building structures), a focus with a self-cutting screw is also a successful solution. To learn how to twist the screw to remove an air bubble from a malfunctioning pipeline section, watch the video:

Suggestion made. Put temporary automatic valves on the heating devices until you investigate the cause of felining if you are continuously drawing air from the heating system through the batteries and are unable to determine what is causing it (possibly a chemical reaction with oxygen release).

We fill in the system correctly

The simplest method for filling pipelines connected to an open expansion tank with water or antifreeze. In order to accomplish this, open all of the valves (apart from the drainage valve) and fill the radiators and highways with coolant by connecting the hose to the fitting fitting. It’s crucial in this situation to take your time and allow the air to exit the system on its own using the expansion capacity.

Advice: Warm up all heating appliances after turning on the boiler and circulation pump after filling. Then use the Maevsky cranes to release the last of their air. Remember to turn off the pump before launching, as mentioned previously.

Now let’s talk about lowering the air in a private home’s closed heating system’s batteries and pipelines. The suggested method, which our expert plumber Vitaly Dashko consistently uses. It is carried out in the following sequence:

  1. Open the entire cutting off of the basic circuits (except for drain).
  2. Crush all radiator cranes, excluding the latest batteries at the ends of the loops so that circulation is circulated through them.
  3. Bring to the work of the assistant. Its task is to be in the boiler room and maintain pressure on the network at 1 bar using the assessment pump or through a branch of the water supply from the water supply.
  4. Having opened the water supply, fill the main highways, expansion and boiler tank. The air should be dumped through the valve of the security group and the air vent at the highest point (if any).
  5. Go to the first radiator from the boiler and at the same time open both taps (slowly). Lower the air through the Maevsky valve and close the valves again. The assistant at this time does not allow the pressure to fall below 1 bar.
  6. Repeat the operation on all batteries, then turn on the circulation pump and run the heat generator. Когда магистрали начнут прогреваться, поочередно откройте все радиаторные краны и повторно удалите остатки воздуха из них.

A crucial aspect. Make sure to scare the air from the circulation pump and turn it on for 5–10 minutes to pump pipelines before attempting to squeeze out air traffic jams from radiators.

Following the complete heating of the heating components, the system pressure ought to be between 1.3 and 1.6 bar. The process is deemed finished on this. The same algorithm (for cold!) must be used to fill warm floors last in the event that they are present in the system. In other words, after increasing the pressure in the main highway, you must successively open and close the floor contours, allowing air to escape through the collector valves, before heating the coolant and adjusting its flow rate.

A comment on the automatic air spacing valve installation. When highways cross over radiators, such a device should always be in the boiler security group, as well as the second, third, and so on. Air builds up in batteries in a one-story house with lower wiring because the batteries are more expensive than pipelines and do not require valves.

Step Instructions
1 Turn off the heating system to avoid any accidents or disruptions.
2 Locate the bleed valve on your radiator, usually found at the top corner.
3 Place a container under the valve to catch any dripping water.
4 Use a radiator key or a flat screwdriver to slowly turn the valve counter-clockwise.
5 Listen for a hissing sound, which indicates air escaping. Once water starts flowing steadily, the air is removed.
6 Close the valve by turning it clockwise as soon as water begins to leak without air bubbles.
7 Turn the heating system back on and check if all radiators are warming up evenly.

Bleeding radiators, or extracting air from your heating system, is a necessary maintenance procedure that keeps your heating system operating effectively and efficiently. Your heating system’s overall efficiency may decrease as a result of air becoming trapped in your radiators over time, creating cold spots. You can improve the heating efficiency of your house and reduce your energy expenses by learning how to properly bleed your radiators.

Radiator bleeding is an easy task that can be completed without expert assistance. The process entails utilizing a radiator key to unlock the tiny valve situated at the top of the radiator, thereby releasing any trapped air that may be indicated by a hissing noise. The radiator has been successfully bled when the air is released and only water begins to drip from the valve. By avoiding uneven pressures and potential damage, this procedure not only increases the efficiency of your heating system but also helps to extend its lifespan.

As part of your regular home maintenance, check your radiators for air buildup on a regular basis, particularly at the beginning of the heating season. This not only guarantees ideal heating but also aids in the early detection of any possible problems with your heating system, averting more serious issues later on. You can have a warmer house and cheaper heating costs by keeping your heating system operating efficiently.

To sum up, bleeding your radiators is an easy but important task for keeping the dependability and efficiency of your heating system. Your home can become more energy-efficient and comfortable with just a little care and attention. Don’t skip this easy maintenance procedure; it will save you a lot of money and improve the heating in your house.

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Michael Kuznetsov

I love to create beauty and comfort with my own hands. In my articles I share tips on warming the house and repairing with my own hands.

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