Air conditioning with an influx of fresh air: the device and the choice of a supply split system

Selection Tips

But it is extremely difficult to choose the right duct ventilation device for an apartment or for a house, just by getting acquainted with the information provided by the manufacturers.

Rather, you can make a choice, but it is unlikely that it will be the right one. It is imperative to pay attention to the reviews of other consumers. It is their opinion that allows you to identify the strengths and weaknesses of each option.

For obvious reasons, it is better to use independent engineers and designers, rather than those offered by the manufacturer, dealer or sales organization.

Professionals will take into account:

• glazing characteristics;
• the area of ​​the glazed space;
• total serviced area;
• purpose of the premises;
• necessary sanitary parameters;
• the presence of a ventilation system and its parameters;
• heating method and technical properties of the equipment;
• the level of heat loss.

The correct calculation of all these parameters is possible only after studying the features of the object itself and a number of measurements. Sometimes you have to use special software for designing air ducts and selecting good duct equipment. Only when the necessary properties of the channels, the need for air intake and the optimal installation locations have been determined, it is possible to take up the choice of the air conditioner itself. It makes no sense at all to take this choice without a project - it’s easier to throw money down the drain in the literal sense

You also need to pay attention to:

• functionality;
• current consumption;
• thermal power;
• possibility of air drying;
• contents of delivery;
• having a timer.

The main factors influencing the choice of ventilation system

Equipment for air conditioning and ventilation systems must be selected in accordance with the conditions of the room or building. This section lists the main parameters that should be considered when developing a ventilation system plan.

Air volumes

Ventilation devices during operation must completely pass through all the air in the room. Depending on the volume of masses that pass through the device per hour of operation, its performance and power are calculated.

Thus, in order to select the right components, it is necessary to know the performance of the ventilation system. To do this, calculate the volume of the room: the area should be multiplied by its height.We multiply the obtained value by a factor of 10 - in this case, we get a value corresponding to the average productivity (m³ / h).

Humidity in the room

Another environmental factor that is regulated by the ventilation system is air humidity. For a person, a comfortable indicator of the moisture content in the air is 40-60%. If this mark is raised or lowered, it is worth choosing ventilation devices that can normalize the level of water in oxygen. It is also worth noting that it is better to measure the humidity level in winter - at this time, heating radiators greatly dry the air in the apartment.

Temperature

Ventilation systems are capable of changing the air temperature, and air conditioners are completely aimed at performing this task. Therefore, it is worth considering this indicator when choosing equipment for ventilation. As already mentioned, the temperature difference in the building and outside is the basis for the operation of natural ventilation. And forced systems can help to successfully regulate this indicator, which is especially important in the warm season.

Inverter effect on noise level and power consumption

In inverter split systems, much is arranged differently than standard air conditioners. In it, the compressor is powered by a DC motor. The control module in split systems converts direct current into alternating current of a given frequency. This process is called inversion.

Such a transformation allows changing the speed of rotation of the compressor motor in a wide range, and, accordingly, the creation of coolness and warmth. The power of the motor is regulated by a simple change in voltage: more voltage - the rotation of the motor shaft increases.

Accordingly, the movement of the refrigerant from the compressor is accelerated. And vice versa, the voltage decreases - the engine speed decreases, and the freon speed through the tubes decreases. In a standard device, a compressor with an AC motor is used, and its power is regulated only by turning the motor on or off.

It turns out that the inverter device is designed to change the standard frequency of the electrical network. An integrated control board is mounted in the device, due to which the operation of the device is regulated. It is located in the outdoor module and regulates the number of times the appliance is switched on.

Consequently, for air conditioners with inverters, the compressor always moves the refrigerant when the split system is turned on in cooling mode (at the same time, its speed is either higher or lower). This has three important advantages:

• There are no starting torques for the engine.
• Possibility of smooth regulation of the movement of cool air.
• The inverter air conditioner in the apartment works in the created mode.

As a result of the first advantage, a split system consumes about 20-25% less electricity than a classic climate control device. The second point indicates that the compressor of the inverter air conditioner operates in the range of 0.5-1˚С degrees (and for standard split systems, the range is 1-5˚С).

The third advantage indicates a quieter operation of the air conditioner. Thanks to this mode, the air conditioner operates silently and is often used in bedrooms at night. At the same time, it switches to an economical mode with a slow rotation of the fan impeller. Inverter wall-mounted air conditioners from Hitachi are especially suitable for this setting.

Device and principle of operation

The first step is to understand how a ducted air conditioner works. The essence of its action is that air masses are transmitted using special shafts and air ducts. The hardware part is mounted as an integral element of the air duct complex, and not just attached to them. Hence the conclusion: planning and implementation of installation work should be carried out at the construction stage. In extreme cases, it is permissible to perform these works simultaneously with a major overhaul.

The outdoor part of the air conditioning unit takes air from the street, and then it is pumped to the indoor unit using the air duct. Along the way, cooling or heating of air masses can be carried out. The standard scheme takes into account that the distribution of air along the highways cannot be created by gravity. The sufficient efficiency of this system is ensured by the use of high-power fans. Air cooling is achieved by the heat exchange part of the evaporator.

But the heat taken from the air must be removed somewhere. This problem is successfully solved with the help of a heat exchanger connected to the condenser of the external unit. Duct air conditioners are in demand in shopping centers and shops. With proper installation, a minimum level of extraneous noise is ensured. Part of the channel technology is designed to use water to remove heat. These are more powerful solutions and their cost is quite high, which limits their practical application.

Air conditioner that takes air from outside

The channel split system uses supply schemes most competently.Does this air conditioner take air from outside? One remote unit is located outside the circuit, the evaporators are connected to it by piping, mounted in a suspended ceiling or false wall. An outdoor air preparation unit is used, which is supplied to the system in several places. Condition - a place behind the wall or under the floor, sufficient to accommodate the equipment. The system is programmable, the regulation is carried out by an electronic unit. The installation for preparing the air supply from the street and the ducted air conditioner have different control panels. The admixture of fresh air can be 30%. As a result of renewal, the balance of carbon dioxide and oxygen content changes.

Installation of freon pipelines

This operation includes the following manipulations:

1. A pair of copper pipes is cut off with a pipe cutter. Their length should be 1000 millimeters longer than the distance between the fittings, which will ensure smooth bends.
2. On the outer parts, the workpieces are bent by means of a pipe bender. Without this device, the metal can deform and crack.
3. The tubes are equipped with heat-insulating nozzles made of polyurethane.
4. Threaded flanges are attached to the edges of the elements.
5. Rolling of the ends of the workpieces is carried out. Tighten the nuts preferably with a torque wrench. Excessive force may damage the device.
6. The ends of the tubes are screwed by means of threaded flanges, which must be tightly tightened.

Variety of air conditioning systems

Multizone air conditioning is a way of organizing the circulation of air masses in several rooms.To the external element, which is located on the roof, in the basement or technical compartment, several indoor units are connected using a single system. This design allows indoor and outdoor units to be placed at a large distance from each other, which is convenient for maintaining design requirements, since the outdoor unit can be placed on the roof or in other places. There can be from one to three external blocks, and many more internal ones.

The system ensures the circulation of freon in certain dosages between the indoor and outdoor units, which allows you to more accurately adjust the temperature.

This organization reduces the cost of cooling and heating. Power is set depending on the preferences of the customer. Consequently, rooms with such air conditioning receive an individual microclimate, specially selected.

Air mass conditioning is the installation and constant maintenance of a certain level of humidity, temperature, cleaning and speed in closed spaces. The goal is to regulate the optimal environment and microclimate that is favorable for human well-being or necessary in the production process. Modern constructive solutions are diverse and their differences are noted in many ways.

Air conditioner device

An air conditioner having an outer and an inner part is the most complex in the device.

Outdoor unit:

• Freon compressor.
• A four-way valve that changes the direction of freon movement.
• Control fee.
• Fan.
• Condenser, cooling or condensing freon.
• Freon system filter that protects against debris.
• Union connections.
• Protective cover.

Indoor unit:

• Front Panel.
• Coarse filter protecting against large debris.
• Evaporator.
• Horizontal and vertical louvers that control the direction of air flow.
• Display panel.
• Fine filter.
• Fan.
• Tray for condensate.
• Control fee.
• Union connections.

Types of air conditioners

In domestic conditions, devices are used, conditionally divided into three large groups:

A mobile (portable) air conditioner is a good alternative to permanently installed climate control equipment. The device can be moved, moved from room to room or transported to another location without installation. Weight from 20 kg. In addition to ventilation and cooling, it is able to reduce the level of humidity in the room. A mobile air conditioner recycles the air in the room: one of the built-in fans sucks in the air mass through a system of holes, and then passes the flow to the evaporator of the refrigeration circuit. During operation, the fan removes heated air masses through the duct to the street and through a system of slotted holes ejects the cooled stream into the room. The body of the portable device is equipped with a condensate collection tray, which is poured out manually.

Monoblock mounted in a window opening

The window air conditioner is a cooling device organized by a single body. It is installed in a window opening, window or wall, the width of which is not more than 30 cm. The device is attractive for its simple installation, operation and cost 30-40% lower than other representatives of the product group. The window monoblock takes part of the room air (up to 10%) and lets it out into the street, providing forced exhaust ventilation.When oxygen is taken from the street, the system begins to make increased noise and cool the air flow worse. In fact, the air conditioner begins to function as an exhaust fan.

The split system maintains the parameters of temperature and airflow speed set in the room. Consists of external and internal blocks. The split system takes the air in the air-conditioned room for cooling and transfers it to the street.

Air conditioner device

Basic and running models of air conditioners are arranged according to the principle of coordinated work of the following main units:

• The compressor compresses the refrigerant (freon) and keeps it moving along the refrigeration circuit. A refrigerant is a working substance of refrigeration machines that takes away heat from a cooled object during boiling.
• The air heat exchanger of the outdoor unit provides the process of converting the refrigerant into a liquid (condensation), as well as its cooling.
• The air heat exchanger of the internal block promotes process of evaporation of freon.
• The capillary tube is responsible for the timely increase/decrease of the refrigerant pressure in the air heat exchangers of the outdoor and indoor units.
• The fan provides a continuous flow of air to the condenser.

Installation and operation

When the equipment is selected, you need to know how to properly install it. Of course, the work itself is done by professionals, but it is absolutely necessary to control their actions. When choosing a place to install an air conditioner, you need to focus on such requirements as:

• the maximum level of sound insulation from residential and industrial premises;
• maintaining a temperature of at least +10 degrees (or reinforced thermal insulation of the indoor unit);
• approximately the same length of all ventilation ducts (otherwise, more or less strong temperature drops will occur along the duct).

Next, you need to figure out which air duct is better. If considerations of minimum air loss are in the first place, round pipes should be preferred. But they absorb excess space. In domestic conditions, therefore, rectangular ducts are the best choice. Most often they are laid in the interval from the draft to the front ceiling, and this must be done before installing the air conditioner itself.

When it is planned only to cool the air in summer, pipelines made of polymeric materials become the best choice. If the consumer is also going to warm up the rooms in winter, preference should be given to steel. In this case, you should also make sure that the size of the pipe matches the size of the pipes installed on the inside of the air conditioner. You need to think about where to put the wall gratings. They must effectively contain any dirt, and at the same time there should be no obstruction to the movement of air from any objects in the room.

All air ducts must be made only from completely fireproof materials. Flexible corrugated piping is not the best solution. It will sag in free areas, and wherever fasteners appear, strong compression will appear. As a result, normal aerodynamic resistance cannot be provided. Both diffusers and grilles must be designed for air movement at the limit mode at a speed of not more than 2 m / s.

If the flow starts to move faster, a lot of noise is inevitable.When, due to the section or geometry of the pipe, it is not possible to use a suitable diffuser, the situation must be corrected with an adapter. Where the air supply lines branch out, areas with reduced internal resistance are equipped with diaphragms. This will limit the movement of air flows as needed and provide the required balance. Otherwise, too much air will be directed to places with low resistance. Very long air ducts require the installation of inspection hatches. Only with their help can periodic cleaning of dust and dirt be carried out. When channels are laid in ceilings or partitions, easily retractable elements are immediately mounted, providing quick and easy access.

Service means:

• cleaning of pallets where condensate flows;
• cleaning (as necessary) of the tube through which this condensate flows;
• disinfection of all components in contact with the liquid;
• measurement of pressure in the refrigeration line;
• filter cleaning;
• removal of dust from air ducts;
• cleaning of decorative front panels;
• cleaning of heat exchangers;
• checking the performance of motors and control boards;
• search for possible refrigerant leaks;
• cleaning fan blades
• removal of dirt from the hulls;
• checking the health of electrical contacts and wiring.

For information on how to properly care for a duct air conditioner, see the following video.

Modern models

When choosing an air conditioner, first of all, you need to pay attention to the power of pressure. It must exceed the resistance of the air ducts

It is also important to take into account the amount of cooled air supply.

As for manufacturers, Japanese and Swedish companies are considered the best, but you can also find good options among budget Chinese devices.

It is also important to consider the amount of cooled air supplied. As for manufacturers, Japanese and Swedish companies are considered the best, but you can also find good options among budget Chinese devices. For comparison, you can consider several modern models from various manufacturers:

For comparison, you can consider several modern models from various manufacturers:

• Energolux is a Chinese firm that offers the SAD18D1-A. This device is designed to serve 50 square meters. The cost is 47 thousand rubles. It also has a night mode to reduce noise levels.
• The well-known manufacturer Electrolux has a model EACD-09 H / Eu for 44 thousand rubles. It is designed to serve 25 square meters, this device has no additional functions.
• Toshiba releases the RAV-SM140, designed for a large service area - 125 square meters. If necessary, such an air conditioner can provide an optimal microclimate throughout the house or a large apartment. Its price is 236 thousand rubles.

If necessary, you can find an air conditioner for any request - to cool a small room or a whole house, with and without additional functions. There are also budget models, this price segment on the market is represented quite diversely.

Comparison of conventional and supply air conditioners

A common mistake among users is that they consider any air conditioning system to be ventilated.In fact, only certain types of equipment can work with outdoor air masses in the active air exchange mode. To make it clearer, first consider the device of a conventional split system.

Household air conditioners, which are commonly called split systems, are a set of two separate modules that have a different structure from each other and are located in different places. The first module is the evaporation unit, which is installed on the floor, hung on the wall or partially masked with a ceiling cladding. The second module is a remote compressor and condenser device, usually mounted on the facade of a building.

Schematic representation of the device with the indoor module mounted on the wall. The two modules are connected to each other by thin copper tubes through which freon moves. The tubes are hidden in strobes behind decorative trim or in plastic boxes (+)

The principle of operation of the air conditioner is simple. Through the intake grilles, room air enters the unit, where it is cooled, and then removed through the air ducts to the outside. The change in air temperature is based not on the production of cold, but on the transfer of thermal energy.

The carrier is freon, which enters the remote module in a gaseous state, and returns in a liquid state. To go into the gaseous phase, freon takes some of the heat from the exhaust air in the evaporator.

In fact, no replacement of air masses occurs, and cooling (as well as heating and filtration) is carried out by recirculation. Supply equipment is arranged differently.An example of a split system with fresh air supply is a duct type device.

Design diagram of a duct air conditioner that performs the functions of ventilation and temperature control inside the room. A mandatory structural element is a heater built into the pipe (+)

Of course, ordinary split systems are easy to install, have many additional functions, have a beautiful modern design, but they, unlike inlets, do not freshen the air in the room - and this is their main disadvantage.

What is the feature of multi-split systems

Speaking about air conditioners in a general sense, it is necessary to mention multi-split systems, which are also used to equip multi-room apartments, private houses, office and industrial buildings.

They differ from ordinary ones in that they have only one remote block, while there can be several internal ones. The minimum number is two modules, the maximum is limited to four. If you use more indoor units, the system will lose its performance and will not work at full capacity.

The number of pipelines increases, respectively, the cost of equipment increases and the installation of some parts of the structure becomes more complicated.

It is important to create conditions for laying all connecting elements (+). A multi-split system is not always used, but only in some cases when the installation of a large number of outdoor units is not possible for a number of reasons:

A multi-split system is not always used, but only in some cases when the installation of a large number of outdoor units is not possible for a number of reasons:

• the building is a historical or architectural monument;
• there is a ban on the installation of remote units on the facade;
• for hanging equipment, the architecture of the building provides for certain places limited in area.

Sometimes, mounting a large number of remote modules is abandoned for aesthetic reasons: the beautiful facade of the building, hung with bulky cases, looks unpresentable.

Amendments are periodically made to the rules for the improvement of large cities, prohibiting the placement of air conditioners on facades overlooking the central streets. Exit - installation of the block on the courtyard wall of the building

The advantage of a multi-system is the installation of one remote module, the disadvantages are complex work on the installation of pipelines, a decrease in productivity and reliability. In addition, all indoor modules must operate in identical modes: either heating or cooling.

Selection of a ducted air conditioner with an influx of fresh air

First of all, the device must be selected according to the main characteristics.

By pressure

The pressure developed by the fan of the indoor unit must exceed or at least be equal to the resistance of the air ducts.

Advice

Those who doubt the correctness of the calculation of air ducts should pay attention to the models of "ducts", in which the pressure can be adjusted over a wide range

By flow (volume of cooled air supply)

The characteristics of the duct air conditioner indicate the maximum supply of cold air, but you need to understand that the device can provide it only with zero resistance on the discharge side, that is, without connecting to air ducts. If they are connected, then the supply, and, accordingly, the refrigeration power, will be the smaller, the higher the aerodynamic resistance of the system will be.

It is important to pay attention to the brand of the air conditioner.The best reputation is enjoyed by the products of companies:

• Daikin, Mitsubishi Heavy, Mitsubishi Electric, Toshiba, Fujitsu General (Japan);
• Samsung Electronics, Lg Electronics (South Korea), Electrolux (Sweden);
• Dantex (Great Britain).

Of the Chinese, the most reliable are air conditioners of the brands Midea, Gree, Ballu.

Some models are equipped with a built-in drain pump. Usually it is low-power - it can raise water by only 40-50 cm. But if it breaks down, the air conditioner will perform an emergency shutdown, so that the user does not face a condensate leak. Another thing is a pump installed separately: the air conditioner will not react to its failure. But among such pumps it is easy to find quite powerful ones - capable of lifting water by 8 m or pumping it through a 20-meter horizontal pipeline.

High-pressure duct-type air conditioner with a drain pump: diagram

If your air conditioner is equipped with a fresh air mixing function and you want to operate it all year round, purchase an electric heater for heating outdoor air in winter. Frosty air must be heated even if the device will work only for cooling, otherwise the flow entering the room will be unacceptably cold.

Tips for choosing air conditioners

Before purchasing a split system for home use or for office use, you must first decide whether ventilation is needed. Perhaps the room is equipped with an efficient ventilation system and does not need additional devices of this type.

If the air exchange is weak, pay attention to the models of supply air conditioners. For rooms with high ceilings, any built-in models are suitable - channel, cassette

But do not forget that in order to mask the working elements, you will have to build a suspended structure.

For rooms with high ceilings, any built-in models are suitable - channel, cassette. But do not forget that in order to mask the working elements, you will have to build a suspended structure.

If the ceilings are low (for example, 2.5 m), the idea of ​​\u200b\u200bceiling models will not work. Perhaps, according to the technical characteristics, it is possible to choose a device with a wall-mounted module, which simultaneously carries out air intake from the street. For large rooms, a more productive model will be required, for example, with a floor-to-ceiling installation.

Hotel halls, foyers and vestibules are large. In addition to channel systems, column models are installed in them, which are distinguished by their productivity and high air exchange rate.

Regardless of the type of device, it is necessary to analyze its technical characteristics and performance: to clarify what area the model is designed for, what is its power, whether it is possible to connect additional modules. The latest programmable air conditioners with a large list of additional options are much more expensive, but some features are really important.