The ubiquitous installation of plastic windows in residential and administrative buildings has led to the fact that fresh air practically ceased to flow into the premises. The lack of natural ventilation leads to a glut of carbon dioxide, which in conditions of lack of oxygen can adversely affect the well-being of people. You can improve the quality of air by installing an air conditioner with forced ventilation for the apartment or a split system that can provide a forced flow of fresh air.
Types of supply air conditioners
An air conditioner capable of supplying fresh air to a room differs from a conventional air conditioner by the presence of a special air duct, the design of which can be different.
Membrane
Air conditioners with a membrane-type duct are not widely used due to the relatively high cost (from 50 thousand rubles) and a complex installation system. The natural level of oxygen in the room is maintained due to the fact that the membrane, which controls the operation of the air channel, has uneven throughput. In this case, oxygen molecules penetrate through it several times better than the molecules of any other gases.
Modular system
Allows you to retrofit an existing air conditioner with a recuperator with an air duct. Structurally, the device is a separate external unit with small ducts. It is installed next to the air conditioning. By the principle of operation, this device resembles a small hood. Due to the fact that the system has limited air exchange capabilities (up to 20 cubic meters per hour), it has practically disappeared from the market.
According to SNiP 41-01-2003 “Heating, ventilation and air conditioning”, the minimum consumption of outdoor air in a room is calculated based on the fact that per person (depending on the ventilation system) accounts for 30 to 60 cubic meters. m. air per hour.
Modification of the external air conditioning unit
Modification of the external unit of an existing air conditioner is the most optimal option, allowing to provide the necessary amount of supply air to the room. It provides for the placement of ventilation and cooling units in the casing of an external device. Air is supplied through the indoor unit of the air conditioner, which is connected by an air duct to the ventilation module. At the same time, the modified air conditioner ensures its supply in an amount of up to 32 cubic meters. per hour, which also does not fully comply with the requirements of applicable regulatory documents. The price of such units is at least 140 thousand rubles, which significantly limits their use in everyday life.
Among air conditioners with a mixture of air, channel systems in which the volume of fresh air flow takes up to 25% of the total are most effective. However, these air conditioners are large and have a complex installation system, so they are rarely installed in apartments.
Split system with forced ventilation function
Ordinary household air conditioners are not able to provide fresh air for living quarters with a disturbed natural ventilation system. One of the most popular ways to solve the problem, experts consider the use of split systems, which are able to work in the supply ventilation mode. Compared to conventional or modified air conditioners, such systems have the advantages of:
- high power;
- silent operation;
- high performance;
- the presence of a variety of built-in devices;
- remote control.
In addition, a split system with fresh air supply has the ability not only to cool, but also to heat the room, which makes it possible to use it in the cold season.
Often multi-room apartments and private houses are equipped with multi-split systems. They are used in cases where it is undesirable to install several outdoor units that can spoil the facade of any house. The composition of such systems includes 1 remote and from 2 to 4 indoor units. However, multisplit systems have a number of significant drawbacks, due to which they are not widespread:
- complex installation;
- low reliability;
- poor performance;
- the operation of the entire system in one mode, the same for all units (either heating or cooling).
To ensure adequate ventilation of the premises, replacing the exhaust air with fresh, only supply systems are able to, which by the principle of operation are similar to conventional split systems, but they differ somewhat in their construction and installation method. They are built on the basis of recirculating duct air conditioners and are capable of supplying up to 160 cubic meters to the room. m. air per hour.
The device and principle of operation of the recirculating duct air conditioner
Structurally, a recirculating duct air conditioner with air intake from the street consists of two units - external and internal.
The external unit contains the main and auxiliary units and mechanisms: a condenser heat exchanger with a fan, a compressor, an automation system, measuring sensors, etc. It is installed on one of the external walls of the building or in other convenient places, possibly protected from sunlight.
The indoor unit contains a minimum set of nodes: the evaporator heat exchanger and the fan blowing it, a temperature sensor, an air purification filter, etc. As a rule, it is built into a suspended ceiling, due to the need for air ducts to be connected to the unit.
A channel air conditioner with air ventilation works as follows: air from one or several rooms is sucked in by the fan of the indoor unit and is supplied to the condenser heat exchanger of the outdoor unit through air ducts. Then it goes back through the air ducts. The main work of such an air conditioner is to process the recirculated air coming from the premises, however, many models have the function of mixing fresh air from the street. The volume of the latter is about 30% of the total air flow.
However, a ducted air conditioner with an air flow is also not able to fully supply oxygen to the premises. This is due to the fact that according to current standards, the air temperature should be in the range of 14 ... 16 ° C.
To heat the supply flows in the cold season, use a special heater, air heater, which is part of the channel split systems with the function of the supply ventilation.
Channel split system with forced ventilation function
Structurally, a split system with forced ventilation consists of:
- indoor unit, which includes a fan, a heat exchanger with a fan, a filter and a control module; an air heater made in a separate case is additionally connected to the unit;
- outdoor unit in which the mixing chamber, a compressor with an air condenser fan, a heat pump and a microprocessor control module are located.
The external block is located on the street. It can also be installed indoors, but for this the unit must be equipped with a centrifugal fan. Between themselves, the external and internal blocks are connected by a thin freon pipeline.The indoor unit is installed behind a suspended ceiling or in a special box.
In the process, the outside air through a thermally insulated duct enters the mixing chamber and mixes with the air received from the room. Then the air mixture passes through the filter and is fed into the indoor unit, where it is processed according to a given program (heating, cooling, etc.) and is supplied to the premises.
The microprocessor control module that maintains a comfortable indoor temperature throughout the year controls the operation of the entire system:
- In summer, it provides the necessary cooling.
- In spring and autumn heats the air masses using a heat pump.
- In the cold season, when the thermometer drops below 0 ° C, the air heater turns on. In this case, the control module provides smooth adjustment of its power, which allows you to maintain a given temperature in the room.
Advantages of ducted split systems with forced ventilation
Modern channel split systems with fresh air ventilation function are developed on the basis of unique engineering solutions and have, in comparison with other systems, significant advantages:
- effective filtration, which is ensured through the use of reusable high-quality filters;
- fresh air at any time of the year;
- simultaneous operation of air conditioning and ventilation systems;
- silent operation of the channel block manufactured using sound and vibration-absorbing materials;
- microprocessor control, with the help of which the set temperature is maintained in the room.
Air-conditioning with a mixed air and a channel split system with the function of fresh air ventilation are most often installed in modern living rooms with sealed plastic windows, as well as where special requirements are made to the composition of the air and ventilation. However, the complexity of ensuring the synchronous operation of air conditioning and fresh air ventilation systems requires the involvement of specialists with experience in carrying out such works. It will not be superfluous for the participation of professionals in the selection of sufficiently complex and expensive equipment.
