A modern duct air conditioner with forced ventilation provides not only a comfortable room temperature, but also ventilation. In addition, additional modules of the air preparation system allow you to remove dust, adjust the humidity of the air environment.
An ionizer and an ultraviolet biologically active filter can be easily integrated into the system. Agree, it is very tempting to immediately normalize the indoor climate. Let's take a closer look at the duct air conditioning system.
The content of the article:
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Features of the device of channel air conditioners
- Air conditioning parameters
- Determination of the required equipment parameters
- Which duct is better?
- Air conditioning installation
- What to consider during installation?
- Conclusions and useful video on the topic
Features of the device of channel air conditioners
Traditionally, chilled air is supplied through channels in industrial premises, large stores, offices, and on ships. However, air conditioners with forced ventilation for a house or apartment are installed less often.
This is due to the fact that the common wall split option is easier to install. But, if you want to provide the best climatic conditions in the rooms, the split system will not be enough.
For example, for a room of 25 sq. m. requires 60 cubic meters. m. of fresh air per hour. Even for expensive wall-mounted split systems with supply ventilation, this parameter is twice as low. It is impossible to build additional effective filters, humidifiers into wall modules. That is why only channel systems.
Air ducts are located between the suspended ceiling and the slab. Only the decorative grille is visible, through which fresh air is supplied at a comfortable temperature
The duct air conditioner consists of two blocks. A block with a compressor is installed on the street. An evaporator with a heat exchange circuit is placed in the inter-ceiling space or in a utility room.
A duct air conditioner is mounted between the suspended ceiling and the ceiling, in the dressing room or in the utility room. The power unit is installed where the sounds from the operation of the equipment will not cause problems. Due to this, the noise in living rooms is significantly less during the operation of the duct system, compared to any other type of air conditioners.
The cooled air flow is distributed between the rooms through heat-insulated ducts hidden in the space between the ceiling. In addition to cooling, the duct system is capable of supplying fresh air in the required volumes.
Agree, this approach is optimal. There is no need to put a grid on the vents, the amount of dust in the room is reduced, and it is easier to regulate the relative humidity of the air.
The diagram shows the principle of organizing the air supply channels to the rooms. Using a special program, you can not only visualize the model of air ducts, but also display the components in a table
As you can see, the use of one duct-type air conditioner is quite enough to cool all rooms in an apartment, house, office or shop.
It is only necessary to correctly calculate the proportions of air exchange, select the power unit of the cooler of the required power, plan the installation of additional air preparation units.
Air conditioning parameters
The first thing to look out for is heating capacity. According to this parameter, a device is selected based on the volume of all cooled rooms.
Second point - air pressure. Long air ducts with bends resist air flow. The longer the channels, the more air pressure you need to create. Distinguish between low-pressure (up to 50 Pa), medium-pressure (up to 100 Pa) and high-pressure (from 100 to 250 Pa) systems.
Blocks with a pressure of 100 Pa are suitable for an apartment. Some models have a pressure switch. This is convenient, since you can adjust the pressure depending on the existing duct, without taking into account the parameters of the ducts.
The next moment is fresh air supply. Not all duct conditioners provide ventilation of premises. The supply ventilation unit is completed with heaters. They prepare the air from the street during the cold season.
It is also necessary to heat cold air in order to exclude condensation on the walls of the air ducts.
Heaters power Is another parameter that is important to consider when choosing equipment. In the southern regions, for a four-room apartment, a block with a forced ventilation with a capacity of 5 kW is suitable.
Supply ventilation unit can be purchased separately. The photo shows a typical container for heating fresh air.
If you plan to install an additional filter in the channel, you should choose an air conditioner with an air pressure of 15-30% more than the recommended parameter.
Determination of the required equipment parameters
At the very beginning, it is determined air conditioning power. In practice, this parameter is taken from the passport of the air conditioner of any system. Then the proportion is drawn up taking into account other volumes of the premises.
For example, a wall-mounted split system with a cooling capacity of 3.5 kW provides room cooling up to 40 sq. m. For an apartment of 120 sq. m. will require a unit with a capacity three times more, 28-30 kW.
Fast calculation has disadvantages. Factors such as sun lighting of windows, methods of shading rooms, the amount of thermal insulation of walls and ceilings are not taken into account. The error can be leveled by a small margin for the considered parameter.
The required air pressure is more difficult to calculate. To do this, make a sketch air ducts. Determine the branching, the total length of the channels. Take into account the resistance of additional filters, air ionization systems.
In addition, you also need to take into account the amount of fresh air. Usually 20-30% of the air from the street is mixed.
Typical sketch of air flows. Knowing the scale, it is easy to determine the dimensions for calculating the parameters of the air supply. An exact drawing is required for the manufacture of channels
All data is transferred to an engineer who is well aware of the characteristics of channel air conditioners of a particular model. Having looked at the sketch of the channels, the specialist will select a system with sufficient air pressure.
As a rule, for four rooms with a total area of 140-200 sq. m. models with an air pressure of 100 Pa are suitable.
Which duct is better?
The air ducts rarely run exactly as indicated in the documentation or sketches. Sometimes you need to go around the beam, often the distances are indicated with an error. Such errors are of little consequence if a corrugated pipe is used. It is cheaper than air ducts with smooth walls and is easier to install.
But there are also disadvantages. Flexible channels sag between suspension points. At the point of attachment, the clamp compresses the pipe, reducing the channel cross-section. All this and the corrugated surface of the corrugation walls provide significant resistance to air flow. A situation may arise when the airflow to the radiator of the indoor unit is insufficient.
In this case, the automatics will work and turn off the compressor. Therefore, it is better to use smooth-walled ducts. They not only offer less resistance to air flow, but they are also less contaminated. And it is much easier to clean them.
In addition, the thermal insulation of the ducts is an important factor that affects not only the efficiency of the air conditioning system, but also reduces the noise in the rooms. A galvanized steel duct is much easier to insulate than a flexible corrugated pipe.
The air duct must be thermally insulated. Then condensation will not form on the pipes. The efficiency of the air conditioning system will increase continuously
Separately, we note that the polymer is not suitable for supply ventilation. Pipes made of polymeric materials have a coefficient of thermal expansion 10 times higher than that of steel. For this reason, the polymer is difficult to match with steel support structures. And the smell of plastic cannot be eliminated.
Air conditioning installation
The easiest way install air ducts and blocks - entrust the installation of equipment to a specialized organization that guarantees the quality of work in the contract.
But even so, you will need to control a number of points:
- the project should provide for easily removable panels for quick access to filters and blocks of the air preparation system;
- fastening of the duct air conditioner, supply ventilation unit, air ducts should not lead to vibration of the suspended ceiling. The load-bearing elements must be made separately, without using the profile of the suspended structure. Then the system will run silently;
- motorized valves must be accessible after finishing work.
During the installation of the drainage system of the duct air conditioner, the elements should be checked and compared with the one indicated in the instructions from the manufacturer. Otherwise, after turning off the system, water can enter the room - this is important for high-pressure systems.
What to consider during installation?
A special large-diameter diamond drill is required to make the channels. It is not possible to make holes with a diameter of more than 200 mm with a conventional punch in panels.
You can mark the grooves yourself. Then invite specialists with a diamond drill (if there is no such equipment on the farm), they will make holes quickly, without disturbing the noise of neighbors.
Using a diamond drill, you can quickly make a hole for ventilation ducts in a reinforced concrete wall or in a ceiling
If you have enough experience, you can purchase ready-made air ducts and combine them into a single system, or you can order the manufacture of air ducts according to sketches are ordered in a workshop working with with tin.
Galvanized steel ducts or round ducts are made on machines, rolling the joints. It will not be superfluous to check each item upon receipt of the kit.
Considering all the recommendations in the article, an experienced craftsman can carry out the rest of the work on his own.
In this case, it is useful to adhere to the instructions:
- The indoor unit of the air conditioner must be placed in service rooms or in the attic if the air temperature does not drop below 10 ° C there. Otherwise, the unit must be thermally insulated.
- Throttle valves are installed at the branching point of the channels. The total cross-sectional area of the openings in the throttles should be 20-30% larger than the cross-sectional area of the supply air duct.
- To reduce noise in systems with a pressure of more than 150 Pa, a muffler is installed at the outlet of the indoor unit - a short section of the air duct with a larger section than the main line.
- The outdoor unit is mounted either on the roof of the building or on the wall. After the installation work, specialists are invited. They will check the tightness of the connections and fill the system with refrigerant.
- When planning installation work, take into account the terms of the warranty. Installation of a duct air conditioner is often required only by official representatives of the manufacturer.
The operation of the air conditioner is adversely affected by power surges. A voltage stabilizer or at least a cut-off device should be provided.
Conclusions and useful video on the topic
The video shows duct air conditioning systems and tells about the operation of ventilation:
A duct air conditioner with a supply ventilation system provides better climatic conditions in the room than conventional split systems.
If you study the manufacturer's instructions and follow the advice of professionals, then mistakes when installing a duct air conditioner can be avoided. Part of the complex work should be entrusted to specialists, and the rest should be done independently. At the same time, the cost of installing the equipment will be comparable to the installation of wall split systems in each room separately.
Do you have experience in installing air conditioning and ventilation in an apartment or house? What difficulties did you face? Please share the information in the comments to our article.
