Repair of ventilation systems: malfunctions and restoration of work

Ventilation units update the air, remove harmful components from the confined space, maintain a comfortable microclimate. Without high-quality air exchange in the room there is a risk to the health of all households. A threatening situation arises in the event of a malfunction of the ventilation system.

We will tell you about how to get rid of stale air, causing problems with the respiratory system, exacerbating chronic diseases. The article we have presented describes in detail the ways in which the ventilation systems are repaired. Provides tips for their recovery and maintenance.

The content of the article:

  • Ventilation options
    • Features of natural ventilation
    • Principles of forced airing
  • Threats of air flow violation
  • How to check the performance of the system?
  • Major faults and remedies
  • System Noise Reduction Techniques
  • Cleaning instructions
  • How to improve the work of ventilation?
  • Useful video on the topic

Ventilation options

Being engaged in the repair of the system, you need to understand how it works, and on what principles it works. There are natural and forced type of ventilation of the premises.

Features of natural ventilation

All old buildings are equipped with natural ventilation exhaust systems. The air flows in them moving, obeying the laws of physics. They enter through the vents, the gaps in the windows and doors, move along the exhaust ducts connected to the common route and exit through the holes in the chimney on the roof of the building.

Natural ventilation is not expensive and easy to maintain, as it lacks mechanical equipment. But there are also significant shortcomings - it responds to weather changes, it does not work well in the summer and does not give the ability to control the air exchange.

The principle of operation of natural ventilation

The movement of air flow in the ventilation of the natural type occurs due to gravitational forces: the difference in temperature, pressure of the air column, wind. To enhance the outflow at the outlet of the pipes are installed deflectors that improve circulation

Principles of forced airing

In modern construction uses heat-saving technologies, providing for the complete tightness of housing. Such conditions provide comfortable living, but impede the natural flow of air into the room.

Therefore, new homes are equipped with forced or mixed ventilation. Here the movement of threads is carried out mechanically with the help of a fan. The intake pipe is located at the bottom of the building, and from it air ducts are connected to the common route from the apartments.

Ventilation consists of a set of devices that facilitate the removal of air over long distances:

  1. Ventilation channels. Flexible and rigid pipelines of plastic, galvanized sheet or aluminum foil, combined into one network with tees, turns and adapters. Provide air supply to isolated rooms.
  2. Fans. Axial and centrifugal devices with a paddle wheel. Serve and remove the gaseous mass, creating the desired pressure in the system.
  3. Air intake grille. Skips external air flows, protects equipment from precipitation and foreign objects.
  4. Air valve. Prevents external air from entering the room when the system is turned off.
  5. Filters. Protect the ventilated space and equipment from dust, debris, insects.

Temperature variations and chimney pressure do not affect the force system. Its efficiency depends only on the performance and power of the fan.

The principle of operation of forced ventilation

The ventilation system, organized by force, constantly replaces the exhaust air, and, if necessary, heats it

However, it is worth considering that such a device consumes a lot of electricity and needs regular maintenance. In the event of a breakdown, the repair of forced ventilation systems can "fly into a pretty penny."

Ventilation systems used in the construction of apartment buildings are described in detail. in the next article, the content of which we advise you to read.

Threats of air flow violation

Disruptions in the performance of the ventilation channels are not immediately noticeable, but sooner or later they result in unpleasant consequences.

The following symptoms are indicative of a malfunction of any type of air exchange:

  • the smell of sweetness and rot appeared in the house;
  • mold and fungus started to multiply actively, both in hard-to-reach places behind cupboards, kitchen sinks or tables, and in open areas;
  • Condensate constantly forms on the surfaces of windows, walls and furniture;
  • it becomes damp, cool in the room, the oxygen supply is not replenished, it is difficult to breathe;
  • the system makes a hum and loud sounds, which causes discomfort;
  • A smell of burning is heard from the air ducts.

The safety of the operation of solid fuel units and gas heating equipment. Ventilation channels are brought out and do not allow harmful combustion products to accumulate indoors.

Condensation and mold on windows are a sign of ventilation failure

If the windows have to wipe out mold and condensate every day, then, most likely, air ducts do not cope with their tasks. This means that it is time to think about the repair and maintenance of the ventilation system.

If at least one of the symptoms of a malfunction occurs, you should immediately begin to diagnose, identify and eliminate the causes of breakdowns in the system.

How to check the performance of the system?

The easiest way check the air in the apartment or in the house - open a window in one of the rooms and bring a thin sheet of paper to the ventilation. Under normal traction, he will hold onto the grid. Such a check is rather approximate.

Fire is not the best way to check ventilation

It is undesirable to conduct testing using matches or candles. Gas can be present in the channels, and even its minimum amount can provoke an explosion or fire.

Calculation tables and an anemometer, a special device that measures air velocity, will help determine the system's performance. After measurements in the table are entered the values ​​of the device and the parameters of the hole cross section. The result is a figure showing the amount of air passing through the mine in an hour.

Anemometer - a device for checking the speed of air movement

The anemometer quickly measures the speed of movement of the air conditioning treatment facility in the ventilation shafts and provides an opportunity to accurately assess the quality of the ventilation equipment.

Normal values ​​of air circulation in the apartment:

  • kitchen - 60 m³ / h;
  • bathroom and toilet - 25 m³ / h.

When there is a real flow rate of gases, it can be used to determine the volume. For this, no additional tables or reference books are needed.

The volume of air passed is calculated without tables using a simple formula:

Q = V x S x 360,


  • S is the cross-sectional area of ​​the hole;
  •  V - the indication taken from the anemometer.

It turns out that at a speed of 22 m³ / h and a cross-sectional area of ​​110 mm, the number of gases being passed in will be: 22х110х360 = 871.2 m³.

Major faults and remedies

Ventilation systems fail for various reasons. Often this is improper installation and operation, ignoring maintenance, the appearance of mechanical damage and corrosion processes, natural wear of parts and devices. All of them are fraught with typical malfunctions. Consider them in more detail.

The most common problem is insufficient air flow in rooms with natural ventilation. Its reason lies in the high tightness of the premises.

The natural system is designed for air inflow from doors, wooden windows and other slots, which we are trying to carefully eliminate during repairs. Tight plastic windows, unlike old wooden analogs, do not allow air, blocking all possibilities for its normal circulation.

The same applies to doors that impede its movement between rooms. Because of this, the windows are constantly accumulated condensate and mold stains.

Air vent for plastic window

The air passage valves “depressurize” the room just as much as conditions require for the normal operation of natural ventilation. They will not affect the room temperature.

The way to fix this problem is to cut small holes in the doors by installing grilles or decorative bushes in them. And also arrange regular through ventilation, install valves with microcirculation function on windows or walls.

The hinged valve for the window is fixed with short screws on the influx of the sash. In-wall intake device it is mounted by drilling the opening and attaching the body with a sealant.

Another problem - difficult exhaust. It can be caused by a garbage canal in the channel, or insufficient power or compressor failure.

To fix this, you will need to clean the air ducts, replace / repair the compressor. The new device should be air-exchange in the amount of not less than 3 cubic meters per hour for each square of the area of ​​the room.

The appearance of unpleasant odors from the ventilation duct cause leaks in the duct, corrosive processes, violation of the integrity of parts.

The way to get rid of the problem: to replace damaged soft inserts, interflange seals, repair or replace parts and elements of the duct with defects. And also adjust the tightness of the connections.

There may be such a problem as a significant deterioration in air quality and increased resistance of the ventilation channels. Its reason lies in the accumulation of pollution in the duct, low efficiency filters.

The remedy is to clean up as much as possible. ventilation duct debris, clean and dry the filters or replace them with new ones.

Replacement of the ventilation grille

Replace worn and overly contaminated filters can each. Thus, high resistance is removed and air circulation through the channels is adjusted.

The emergence of loud noise from air ducts is associated with the penetration of insects, birds, small rodents into the pipeline, insufficient lubrication of moving parts of equipment, and strong wind.

To get rid of the problem, it is necessary to attach self-tapping screws on the sockets of the supply / exhaust channels protective net, regularly lubricate the mechanisms, wrap the pipe with sound-insulating material, install silencers.

Repair of the ventilation system by specialists

If it is necessary to replace individual parts and carry out a major overhaul of ventilation, it is impossible to do without the help of an experienced specialist. Otherwise there is a risk to do more harm than fix.

It is recommended to perform only routine maintenance of ventilation systems on your own, which does not involve significant interference with the design and complicated dismantling. For example, sound insulation or cleaning of the ventilation channels. In most cases, this is sufficient to correct the basic faults.

System Noise Reduction Techniques

Fans, valves, air ducts and forced ventilation flaps create certain sound vibrations that can be heard in a room. According to sanitary and construction standards, the noise level should not exceed 30-40 dB. Violation of the norms is signaled by chronic fatigue, headaches and other health problems.

The noise that occurs during operation, is aerodynamic or mechanical. In the first case, it appears due to poor depreciation, the unsatisfactory state of the nodes, friction and violation of balancing parameters. In the second - is the result of the operation of electric motors, fans.

The following measures will help reduce the noise of the ventilation system:

  • installation of the fan on the vibration-insulating bases;
  • careful adjustment of parts and balancing rotating parts;
  • strong fixation of the fan, valves and valves;
  • installation of a removable soundproof casing;
  • insert rubber or canvas liners between the fan and the duct;
  • lining the internal surfaces of air ducts with materials that absorb sound (fiberglass, mineral felt);
  • greasing of mobile elements of the compressor.

In natural-type ventilation, noise is strongly noticeable in windy weather, because getting into the system at high speed, the wind creates a strong hum. It can cope with a chamber, plate or tubular silencer, reducing the sound pressure on the walls. It is installed in the upper part of the exhaust pipe.

Mineral wool for the duct

Mineral wool from proven manufacturers in rolls 5 cm thick will be suitable for sound insulation of ventilation channels. Insulation not only absorbs sound, but also maintains optimum air temperature, prevents condensation and protects the structure from fires

Another way to compensate for vibration - arrangement of the concrete frame around the duct on the roof. If technical reasons do not allow to perform such an operation, the channel is wrapped with insulation.

Cleaning instructions

Dust, small debris and kitchen grease, which constantly accumulate in the ventilation ducts, cause numerous breakdowns and poor-quality system operation. It is possible to prevent undesirable consequences through routine cleaning in the system, carried out every 3-6 months.

Trying to clean the duct, it is desirable to follow a certain procedure:

  1. Wear tight protective gloves and a mask, prepare a working stable stepladder or chair.
  2. Remove all air vents, wash them with detergent and then rinse thoroughly. If they are badly worn, replace them with new ones.
  3. Clean the inner walls of dirty crusts with a small construction spatula (plastic, wooden or rubber), making sure that it does not deform or damage the canal.
  4. Vacuum the hole in accessible places and wipe with a damp sponge.

AT enforcement system instead of a lattice in the niche is an exhaust fan. It is pre-turned off and carefully removed, unscrewing the screws that secure the case. Then wash the blades and the grate with a special tool that breaks down fat, and wipe dry.

To fully restore normal air circulation, you need to try to clean the canal as deeply as possible using an improvised tool. It is necessary to move carefully, with gradual rotational movements.

At the end of the work, a control check of the anemometer or a piece of paper is carried out.

Hand tools for cleaning ventilation

Making a tool for cleaning the ventilation channels is easy. For this fit a strong and long steel cable. To him you need to attach an ordinary brush and a small load.

It should be remembered that tenants of apartment buildings are not allowed access to the main mines. Therefore, if cleaning a part of the canals inside the apartment did not solve the problem, it makes sense to call special services.

They carry out effective large-scale processing with a vacuum cleaner and a brush machine, disinfect the inner surfaces of pipes with chemicals.

Contamination in the ventilation duct

Air vents clog quickly. During cleaning, a lot of waste can be dumped from them, up to the remains of rodents and insects. The surface of the floor under the vents should be free from furniture and covered with newspapers or film

You can disinfect the channels by preparing an inexpensive universal solution of chlorhexidine, boric acid, fir oil and alcohol. Ingredients are placed in the spray, which are processed and the walls of the ducts.

Disinfecting treatment will eliminate allergenic factors, neutralize all microbes and bacteria living in the pipes. It should be carried out at regular intervals immediately after cleaning the exhaust ducts.

How to improve the work of ventilation?

Any damage is always easier to warn than to fix. This will save manpower and funds to call the master and buy new equipment to replace the broken.

Simple preventive measures will help:

  • checking the force of ventilation;
  • maintaining the cleanliness of the ventilation grilles;
  • visual inspection of air ducts, fixtures, equipment;
  • lubrication of moving mechanisms, fan cleaning;
  • airing the premises.

The main condition is the regularity of these activities. For example, the quality of the thrust force is checked annually, the channels and equipment are cleaned as they become contaminated, a visual inspection is required every few months.

Useful video on the topic

Video # 1. How to independently check the work of ventilation shafts:

Video # 2. What to do if ventilation is not working well:

Video # 3. Instructions for the arrangement of sound insulation Ventkanal:

Ventilation - the most important engineering network of the building, which is entrusted with serious functions. Paying enough attention to prevention, you can save the system from global breakdowns and do maintenance repairs, easily managing without the participation of specialists.

Tell us about how to repair the ventilation system in your house / apartment. Share with site visitors information that will be useful in practice. Please write comments in the block below, ask questions, post photos on the topic.

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