Among all types of climate control units, of particular interest is the ducted air conditioning system, which provides the supply of treated air through a network of air ducts in several adjacent rooms without cluttering the interior with unnecessary equipment modules.
The device and principle of operation of the channel system
Like any split system, the duct system consists of two modules: a compressor-condenser (external) and an evaporative (internal), which are interconnected by a copper pipeline with freon and electric wires. The external module is installed outside the building, and the installation of a room module involves several placement options:
- in a false ceiling;
- in the false wall;
- in the pantry, in the attic, in the back room.
The hidden installation of the evaporating unit makes the use of this type of air conditioner a very practical solution for original design projects.
There are certain peculiarities in the way the duct air conditioner is arranged and works. Such devices are supplied without a complete air distribution system. It is provided when creating a project.
Design work and the subsequent installation of a duct air conditioner in an apartment or semi-industrial premises are carried out at the stages of construction or overhaul of this facility.
Iron or flexible air ducts are connected to the adapters (special holes) of the indoor module, which lead to the adapters with grilles extending to the surface of the ceiling or wall. Air circulation takes place through them. The air ducts themselves are sound and heat insulated to eliminate excess noise and condensation on the structure.
The air intake goes through the exhaust adapter through the air ducts and enters the indoor unit. There it passes through a mesh filter, the evaporator and cooled down into the air ducts connected to the supply adapter.
One of the features of how a duct air conditioner works is the air temperature at the outlet of the indoor unit. She's cold enough. To minimize the temperature difference between room and cooled air, it is necessary to select the correct supply grilles. The best option would be slotted ones, since it is this type that is able to issue cold streams in thin jets and mix them as quickly as possible with warm air in the room.
Supply unit and fresh air admixture
If there is a need for air flow from the street, then the ducted air conditioning system has the ability to take air masses from the outside. To organize such a process, you will need an air supply unit, to which they connect another air duct and cut it into the supply adapter. In order for the outside air to enter several local points in the room, usually the ventilation pipe (air duct) coming from the supply unit is divided through a distributing tee into the required number of branches.
The supply unit is a standard module with holes on the sides. It consists of:
- fan;
- Heating element;
- electronics unit;
- pocket filter;
- dampers.
In summer, the heating element does not work, and in autumn and winter it heats the incoming air to the required temperature.The dampers are needed to block the outlet of the unit, through which, in standby mode, cold streams can enter the air ducts, and then into the room. A pocket (bag) filter is a one-stage filtration system used in supply ventilation systems. It cannot be regenerated, so most often it is replaced with a new one.
The supply unit and the duct air conditioner with fresh air admixture have two different remote controls. The supply module operation is regulated separately.
But it should be borne in mind that in ducted air conditioners, the fresh air inflow is only 30% of the total air flows circulating through the system. No channel air conditioner can mix 100% of street air.
Winter work
The ducted air conditioner has the ability to operate all year round. In this case, the outdoor unit is installed in a room where the minimum temperature is -3-5 ° C and there is space for the warm air to escape. If there is no possibility of installing an external unit in the room, then it is simply equipped with a "Winter start" device, which consists of three separate devices: compressor oil heating, fan speed controller and drain heating. But electricity consumption will increase significantly.
With the correct selection of the power of the air conditioner and the correct laying of the network of ventilation pipes, the terms of trouble-free operation reach 10-15 years.
Types of duct air conditioners
All manufacturers produce models that function either only for cold or cold / heat. Channel air conditioners with fresh air admixture can be with inverter and non-inverter type of compressor control. These split systems differ not only in cooling capacity, but also in blowing power, that is, the head of the outgoing flow. There are low-pressure, medium-pressure and high-pressure ducted air conditioners. The choice of the length and configuration of the air ducts depends on the head force (static pressure) that the fan creates.
Low pressure air conditioners
This air conditioner has a maximum static pressure of 45 Pa. It can handle air in one room, and the length of the ventilation line is no more than a meter. Install low-pressure models in hotel rooms, small offices and apartments.
Medium-pressure air conditioners
For medium-pressure systems, the pressure force can reach up to 100 Pa, and the total length of the air ducts is measured in tens of meters. They are considered the most in demand, as they maximally satisfy the needs of apartments with several rooms, small cottages, cafes, medium-sized offices and shops.
High pressure air conditioners
The head force of such models is up to 250 Pa. The length of air ducts can exceed a hundred meters, and their configuration can be complex and maximally branched. They install high-pressure duct air conditioners in large offices, conference rooms, large restaurants and residential buildings with many rooms.
To remove the condensate accumulated during the operation of the device, a duct air conditioner with a high head force is usually equipped with an additional discharge pump. These devices have the highest performance in comparison with low and medium pressure. All of the above characteristics help to distribute air even to remote rooms without any losses and in full.
Duct air conditioners with fresh air admixture are devices with a high pressure force.
What you need to know when buying
There are practically no drawbacks in the quality of the functioning of this climatic equipment, with the exception of the following nuances.
The height of the ceiling in the room must be at least 3 meters, otherwise the strong air currents coming out of the adapter with the grill will not have time to be distributed over the space, which will cause colds.
A duct air conditioner with all additional structures is mounted in the space between the ceiling and the false mezzanine. Its height must be at least 25 cm.
Only the same parameters can be supported in different rooms. This is not entirely convenient if one of the zones is on the sunny side, where a lower temperature is required, and the other on the north, where averaged indicators are sufficient.
Installation of a duct air conditioner
If you do not want to spoil the facade of the building with many external blocks, and clutter the rooms with internal modules, the correct solution would be to install a duct air conditioner, both in an apartment and in a private house.
In theory, everything is simple - observance of the phased work should ensure the normal functioning of the device in the future. But there are some difficulties in which the installation of a channel air conditioner with your own hands becomes simply impossible, namely:
- laying of a network of air ducts with the calculation of their cross-section and high-quality sound and heat insulation;
- calculation of power, static pressure, air capacity;
- providing access to the indoor unit for subsequent preventive maintenance;
- cutting off some rooms (toilet, kitchen) from the air intake system;
- installation of the air handling unit, if a high-pressure duct air conditioner with fresh air supply is required.
It is useless for an ordinary person to try to understand all the features of installing a duct air conditioner, therefore, even with a very strong desire to do everything with your own hands, it is better to entrust this process to professionals. They will calculate everything accurately, make a project in a short time and help you choose the right unit.
In the skilled hands of the master, the process will take no more than a week, and the risk of spoiling expensive equipment and installation materials when installing a channel air conditioner with your own hands is very great.
In fact, such an installation is a miniature centralized air conditioning system with a simplified control scheme and placement of all elements. It helps to do without unnecessary appliances in several rooms at the same time and qualitatively renews stagnant air with fresh air.
