CLEANING VENTILATION SYSTEMS from Alan's blog

Cleaning ventilation systems is essential for their normal functioning. They regularly pass large volumes of air through themselves, due to which dust, dirt and other sediments accumulate on the walls. This reduces the efficiency of its work, and with a low throughput, it completely blocks air circulation. Therefore, regular cleaning of the ventilationairduct cleanersis a must to ensure the proper operation of this system.

Clean ventilation is necessary for the passage of fire safety, and in medical institutions it is completely obligatory, because the health of patients and employees depends on it. Therefore, do not neglect this.

During operation, dust and grease deposits accumulate in the air ducts and equipment of ventilation systems, which makes it difficult to maintain the specified air parameters. Dirty air ducts in ventilation and air conditioning systems create the possibility of fires. Dust and grease deposits accumulated in ventilation equipment and air ducts are easily ignited, and with the movement of air inside the air ducts, the fire quickly spreads throughout the building.

If the ventilation system, in addition to transporting air, is designed to heat, cool and humidify it, then the accumulated dust deposits create a fertile soil for the growth of ticks, bacteria, fungi and other microorganisms that are dangerous to humans. Over time, microorganisms can detach from the surface of the air ducts and be carried by the air stream into the serviced premises. Diseases such as allergies, influenza, and SARS can be transmitted through ventilation from an infected person to a healthy person.

Surveys are carried out using multimeters (flow rate, temperature, humidity, dust concentration by particle fractions), sound level meter and video equipment, in order to determine the state of vertical and horizontal channels, the reasons for ineffective ventilation, as well as to control the quality of cleaning ventilation ducts.

During the examination, a high-sensitivity video camera mounted on a self-propelled minitractor is used. The image is fed to the monitor, which makes it possible to quickly assess the condition of the air ducts, as well as record the examined areas on a videotape.

After cleaning, repeated video diagnostics of the air ducts is carried out, the record is attached to the work protocol. Based on the results of the survey, a report on the research carried out, a survey protocol is drawn up. If necessary, recommendations are given on the creation of air purification systems in the supply and exhaust ventilation systems and for solving technological problems.

After determining the degree of contamination of the vertical and horizontal channels, a work plan is drawn up with a list of equipment used. Cleaning of the air handling unit of the ventilation system, as well as of its individual components, is carried out using compressed air and highly efficient industrial vacuum cleaners.

Air ducts are cleaned mechanically and chemically. The treatment equipment consists of a wide range of installations and tools for solving specific tasks:

• installation with pneumatic drive and turbine for brush rotation,

• electromechanical treatment plant,

• installation for chemical treatment of air ducts,

• high pressure vacuum and injection unit,

• filtration unit, etc.

This method of cleaning ventilation ducts is effective and safe. It allows you to clean air ducts without dismantling and does not pollute the premises, due to the use of highly efficient filtering units.

You can do this work with your own hands, but it is important to remember that for this you need to use specialized equipment, without which it will be difficult to get the perfect result. It is also important to know exactly what elements the entire system consists of, as a result of which you will need to take care of cleaning each component.

Most often, fat removal is performed, which is quite simple to carry out, but if you concentrate on this work, then it is recommended to immediately implement other related work in order to get a comprehensive cleaning. It is important not only to get rid of grease and dust, but also from various deposits of bacteria and microbes. If there are any blockages in the air ducts, then they must be promptly eliminated, since in most cases they cause serious problems with the air in the premises. It is best to have unique video equipment at your disposal that will make it easy to diagnose mines and canals.

How is ventilation cleaned from dust and other contaminants? For this, it is important to cleanse the following elements:

• Cleaning of ventilation shafts and chambers;

• Work with valves;

• Removal of deposits inside the impeller of machines for exhaust or air supply;

• Purification of impurities accumulating in air ducts with both large and small cross-sections;

• Replacing various filters as needed.

The most significant difficulties usually arise when cleaning the crankcase ventilation, as well as when you have to work with air ducts located in very tall and large buildings, since they are located at a significant height and also have a significant diameter. In this case, the presence of special equipment for this work is considered mandatory. To get the perfect cleaning result, it is important to constantly use various brushing machines and just ordinary hand brushes, which should have different degrees of hardness and dimensions, in the process of work, since then the most optimal option can be selected for a certain contamination. Also, if you have to work in large channels, you need to wear special protective clothing.

The cleansing process itself takes place in several stages:

• Assessment of the condition of the existing ventilation system;

• Finding the right equipment and other cleaning agents for the job;

• Direct cleaning from fatty deposits and other contaminants, and for this a mechanical method or a chemical one can be used, and in the first case, a variety of equipment is used, and in the second, different chemical reagents;

• Evaluation of the work done, on the basis of which it is possible to decide whether it should be supplemented by other stages or an ideal result has been achieved.

Contaminated ventilation and air conditioning systems create the potential for fires. Dust and grease deposits accumulated in ventilation equipment and air ducts are easily ignited, and with the movement of air inside the air ducts, the fire quickly spreads throughout the building.

The most dangerous, from the point of view of a fire, are the air ducts of the exhaust systems from the equipment of the kitchens of restaurants, cafes, etc. Often the cause of a fire is the untimely cleaning of kitchen umbrellas and air ducts from accumulated fat deposits.

In many national cuisines there are dishes prepared in a "live" fire. During the preparation of such dishes, the flame can easily spread from the dishes in which the dish is prepared to the grease traps of the kitchen umbrella and move inside the ventilation system to other rooms. Removing grease from the air duct behind the kitchen umbrella is a rather laborious task, therefore the air duct is often left unattended.

Every building that has an exhaust system above the kitchen equipment has a potential fire risk.

Ventilation cleaning equipment today is extensive and quite popular, so choosing the right one is actually not so easy. However, if you intend to carry out all the work yourself, then you can select the most basic and standard components that will remove dust, grease and blockages in mines and other parts of the system. These include:

1. The core, with which you can check the channels for deposits or blockages;

2. A rod, which is highly flexible, and at the same time, it provides easy access to those ventilation areas that are located in a horizontal position, therefore, difficult to access;

3. A brushing machine, which, if desired and available, can be replaced with different hand brushes;

4. Channel punch that easily handles blockages, and they can even be created from bricks or construction debris;

5. A video surveillance system that will allow you to get information about where there are blockages or deposits in the system.

The frequency of cleaning may vary from system to system. It is best if this complex work is carried out at least once every six months, however, the system is often used very often, and as a result, cleaning will need to be carried out more often. If there is a special industrial enterprise at which impurities in the air constantly appear, which are eliminated with the help of a ventilation system, then cleaning work should be carried out about once or twice a month. Fine filters can easily tell when to replace them, as they will easily show various contaminants and deposits. In this case, you can independently decide when the need for cleaning work arises.

Professional cleaning of air ducts from fat and other harmful deposits is performed using specialized chemical reagents:

• aggressive alkaline compositions for cleaning channels with a foam method;

• neutral powder remover for soft blasting.

Clarification. Blasting is a procedure similar to sandblasting contaminants. Only instead of sand, finely dispersed chemical powders are used that do not damage the zinc coating of the ventilation duct. The technology is effective, but quite expensive.

Alkaline agents are sprayed inside the ducts beforehand or during the cleaning process. Under the influence of the reagent, fats and soot decompose, the sediment is washed off with water.

The type and concentration of disinfecting antiseptics is selected according to the results of the study of samples (so-called swabs). The latter are taken at the stage of inspection or primary cleaning of air ducts and sent to the laboratory.

At the first stage, a treatment plan is drawn up. The ventilation scheme is studied, the places of connection of the machines, the points of setting the plugs and the amount of installation work are determined. Note. In the process of servicing the ventilation system, one cannot do without partial disassembly and reassembly of the elements. Example: To connect a pipe from a vacuum pump, you need to remove the inspection hatch or disconnect the molded part of the air duct. If there are no hatches at the desired points, installers cut openings in the channels and install sealed covers.

In addition to the air channels, the following ventilation elements are cleaned:

• intake and exhaust devices - grilles, diffusers, local suction umbrellas;

• fire-retardant and check valves, control dampers;

• heat exchangers for air heaters, recuperators and central air conditioners;

• parts of fans in contact with the air flow - impellers, turbines;

• grease filters designed for regeneration (restoration).

The equipment and ventilation network are also cleaned from the outside. Cell, pocket and bag filters are completely replaceable. Upon completion of the work, the organization draws up an act approved by the customer.

The technological operation for dry cleaning of the air duct network looks like this:

1. The vacuum machine is connected with a hose to the main air line, usually next to the fan. Extended collectors of large diameters are divided into sections of calculated length, comparable to the productivity of the machine.

2. The second corrugated pipe connects the filter unit to the vacuum fan.

3. Along the entire length of the serviced area, ventilation grilles are removed, branches of a smaller diameter are disconnected. The holes are tightly closed with plugs.

4. The operator of the brushing machine, wearing a protective suit and respirator, pulls the flexible shaft with the cleaning tool into the channel on the other side. To remove fat, an alkaline reagent is preliminarily sprayed there.

5. Both units are started up and the duct is cleaned. Dust and soot removed from the walls with a rotating brush are sucked in by a vacuum unit. The dirty air is fed through a pipe to the filter unit, which traps all particles.

6. The operation is repeated in subsequent sections in the same way.