Air conditioning with an influx of fresh air: the device and the choice of the inlet split system
In warm and comfortable homes often have problems with natural ventilation, and therefore the oxygen content drops sharply. This affects the health and activity of homeowners and employees of enterprises.
To solve the problem using forced ventilation type. Modern air conditioning with an influx of fresh air - a sample of efficient and affordable climate control equipment.
Comparison of conventional and air conditioners
A common mistake among users is that they consider any air conditioning system to be ventilating. In fact, in the mode of active air exchange with street air masses only certain types of equipment can work. To make it clearer, to begin with, we consider the device of a conventional split system.
Air conditioners for domestic use, which are called split-systems, are a set of two separate modules having a different structure and located in different places. The first module is an evaporative unit, which is installed on the floor, hung on a wall, or partially masked with a ceiling lining. The second module is an external condensing unit, usually mounted on the facade of a building.
The principle of operation of the air conditioner is simple. Through the intake grilles, the room air enters the inside of the unit, where it is cooled, and then discharged through the air ducts to the outside. The change in air temperature is not based on the production of cold, but on the transfer of thermal energy.
The carrier is freon, which enters the remote module in the gaseous state, and returns to the liquid. To enter the gaseous phase, freon takes some 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 the organization of fresh air intake is a duct-type device.
Of course, ordinary split systems are easy to install, have many additional functions, have a beautiful modern design, but they, unlike fresh air, do not refresh the air in the room - and this is their main disadvantage.
What is the feature of multisplit-systems
Speaking of air conditioners in a general sense, it is necessary to mention multi-split systems, which are also used for the equipment of multi-room apartments, private houses, office and industrial buildings.
They differ from the usual ones in that they have only one remote unit, whereas there may be several internal units. The minimum number is two modules, the maximum is limited to four.If you use a larger number of indoor units, the system will lose its performance and will not work at full capacity.
Multisplit-system is not always used, but only in some cases when the installation of a large number of outdoor units is impossible for several reasons:
- the building is a historical or architectural monument;
- there is a ban on the installation of remote blocks on the facade;
- for hinge equipment architecture of the building provides for certain places, limited in size.
Sometimes the mounting of a large number of remote modules is abandoned for aesthetic reasons: a beautiful facade of the building, hung with overall buildings, looks unpresentable.
The advantage of the multisystem is the installation of a single remote module, the disadvantages are the complex work on the installation of pipelines, a decrease in performance and reliability. In addition, all internal modules must operate in identical modes: either for heating or for cooling.
Stitched channel models
The function of replacing waste air with air from the street is fully realized only in channel air conditioners, so we will analyze their performance characteristics in more detail. Properly designed and installed channel split-system copes with the tasks of ventilation, and with the control over the indoor microclimate.
Distinctive features of air conditioning with influx
Recirculating models of ducted air conditioners (KK) are similar in principle to conventional split systems, but they differ in design and installation site. Internal modules are built into the suspended ceiling structures, and air is circulated through the channels connecting them to the outdoor unit.
This is a simple recirculation model that cannot supply fresh air. For the system to perform the supply function, a built-in heater is required. This is governed by the rules of SNiP, according to which the lower threshold for the temperature of air masses coming from the street should be +14 ° C.
If the outside air temperature is above -15 ° C, the heat pump manages the heating function. However, at lower temperatures, models of air conditioners with water or electric heaters are used. The equipment performing the heating can be either additionally installed or built-in.
Programmable intake systems are more expensive than ordinary room modifications with wall mounting, but they are much more efficient and functional because of the combination of ventilation and air conditioning.The amount of oxygen in the air meets sanitary requirements, the temperature is easily regulated, and the appearance does not create discomfort, since all the working parts of the system are in the invisible zone, above the ceiling.
The principle of operation of the supply system
To transport air from the street to the premises, air ducts are provided, which conventional split systems do not have. First, the air from the street through the outdoor unit is moved to the insulated channel, then - in the mixing chamber. There the incoming air connects with the exhaust, refreshing it.
Then the air mixture passes through the filters and, according to the selected mode, is processed. There is a drainage, heating or cooling of air masses. After that, purified, filtered, partially refreshed air of a given temperature enters the premises.
As a rule, the temperature maintained is completely dependent on the season.In the summer, the inlet ducted air conditioners operate on cooling, in the winter - on heating. In the cool season, it is enough to operate the heat pump, the heater during this period can not be used.
Types of equipment with mix
As you already understood, only duct equipment with air ducts and heating can cope with the replacement of air with fresh air. However, some other types of models can also provide ventilation, but within 10% of their performance. The share of fresh air is often referred to as “mix”; the main part of the air masses is occupied by the “working out” processed in the internal unit.
Traditional wall models
Models, the indoor unit of which is mounted on the wall, are the most popular for the improvement of residential premises. There are models that provide a comfortable microclimate on an area of 10 m², but there are also more powerful equipment designed for rooms up to 100 m². Not so long ago, inverter models equipped with a supply and exhaust fan appeared.
Regardless of whether the air conditioner is operating in heating or cooling mode, a supply and exhaust system can function in parallel.An example of a wall device with the function of air supply from the street is the Air Exchanger series of the famous brand HITACHI.
The wall-mounted evaporative unit is installed anywhere in the room, but a zone near the window is preferred. The shorter the line between the indoor and outdoor units, the higher the productivity of the equipment. Wall models have a pleasant design and a large set of additional options.
Cassette air conditioning systems
Often in public buildings can be found air conditioners with internal modules of cassette type. Such systems are suitable for servicing large areas - from 40 m² to 150 m². They have high performance and compare favorably with minimal noise figures.
The performance of cassette air conditioners - from 3 kW to 15 kW, the main functions - lowering the temperature in the hall or work in the heat pump mode. A structure is widespread in which air is taken from the hall through the central opening, and the supply is carried out along four guides in different directions. If one cassette is used, then it is mounted in a suspended structure in the center of the room.
On the market, you can find both traditional modifications and cassette mixes. For example, Airwell CK air conditioners are designed for installation of multisplit-systems and, thanks to the built-in heater and air ducts, carry out a metered supply of fresh air. Advantages - beautiful design and high performance, disadvantage - installation only in the suspended structure.
In some rooms there are no conditions for installation of cassette models, and the performance of wall-mounted air conditioners is not enough. In this case, use universal floor-ceiling devices that are mounted and for installation on the floor, and for hanging from the ceiling.
Air conditioning is provided by a stream of purified air, which is sent along the ceiling or wall - depending on the installation site. The highest power of the devices is 15 kW, but for relatively small rooms (40 m²) there is enough equipment with parameters of 5-6 kW.
Column models of split systems
As the name implies, air conditioners in their form resemble columns directed towards the ceiling. They are superior to other types of power (an average of 17 kW) and can serve rooms up to 180 m².
The principle of operation of the column type models is the same as in previous air conditioners, however, they differ in the supply of purified air. The jet is directed not along the walls and not in the center of the room, but towards the ceiling. There, the cooled air diverges in different directions and falls, displacing the already heated.
Recycling models with a partial mix of clean air have high performance, but the noise level they have is higher than that of steel types - up to 50 dB.
The advantages of multi-zone air conditioning
Multizone room maintenance is a more advanced version of multi-split systems, which creates a certain microclimate over a large area. The principal difference from standard split-systems is the increased length of highways connecting modules placed in various places.
Advantages of a multizone system:
- up to 20 internal units can be connected to 1 remote unit;
- the distance from the internal module to the external one is up to 150 m (in some cases more);
- height difference between modules - 50 m.
Thanks to the listed parameters, the external outdoor module is installed in the most convenient remote locations - in the attic, roof, in the courtyard behind the fence, etc.
A multizone system is more economical, since inverter control allows you to change the power of the system depending on the number of functioning indoor units. In this case, it is possible to apply modules completely different in type and performance.Adjustment and control over the operation of all equipment can be performed in system mode, from one remote control.
Tips for choosing air conditioners
Before purchasing a split system for home use or for office use, you must first decide whether you need ventilation. Perhaps the room is equipped with an effective ventilation system and does not need additional devices of this type.
If air exchange is weak, pay attention to the models of air conditioners.
If the ceilings are low (for example, 2.5 m), the idea of ceiling models will not work. Perhaps, according to the specifications, you can pick up a device with a wall-mounted module that simultaneously carries air from the street. For larger rooms will require a more productive model, for example, with floor-ceiling installation.
Hotel lounges, lobbies and lobbies are large.In addition to channel systems, column models are installed in them that differ in performance and high air exchange rate.
Regardless of the type of device, it is necessary to analyze its technical characteristics and performance characteristics: to clarify what area the model is designed for, what its capacity is, and whether it is possible to connect additional modules. The newest programmable air conditioners with a large list of additional options are much more expensive, but some features are really important.
Conclusions and useful video on the topic
In order to better understand the structure and principle of operation of the inlet split-systems, we suggest viewing video clips of an overview.
Haier duct air conditioners video review:
About the advantages of channel type models:
More about multizone systems:
To enrich the air in the room with oxygen, it is not necessary to keep the window open or install additional ventilation. Sometimes it is sufficient to correctly select the model of the air conditioner, which, if necessary, will not only cool / warm the room, but also air exchange.