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Brief introduction of fan coils
The fan coil is one of the components of the air conditioning system that is used for air conditioning and temperature control. To get more acquainted with the fan coil, we go to its construction, of which the fan and the coil are the main parts:
- Copper coils, which are the passage of hot and cold water and indirectly cause water to come into contact with air.
- Blower or blower that creates airflow.
- The motor is responsible for providing electronic energy for the blower to rotate.
- Air filters to prevent particles and dust from entering the system
- Vent valve, which is used to control the air.
- Controllers that appear in the form of buttons, keys and screws.
- The thermostat, which is responsible for setting the right temperature, is available in different types depending on the needs of the device.
What are the drawbacks of fan coils?
Disadvantages of fan coil related to how it works
Lack of new ventilation system
The function of the fan coil is defined in the scope of functions of all air conditioning systems, which is the control and supply of heating and cooling air. This is done in the fan coil in such a way that the existing air is passed through the coils that contain hot or cold water to increase or decrease the temperature and reach the desired temperature. Disadvantages of this method of operation are the lack of fresh air and the lack of fresh air in the fan coil. This means that the fan coil does not introduce fresh air into the environment, but simply takes the ambient air, brings it to a more favourable condition and returns it to the environment.
This causes the used air to be used again and again, and not entering fresh air from outside the environment or the building means not having enough oxygen. In fact, the fan coil does not have a system for getting fresh air. However, under standard conditions, the best air conditioner is the one in which the airflow is done with the entry of fresh air. In this case, the fan coils need an auxiliary device to be able to provide the required oxygen and fresh air from that device.
Condensation occurs in summer
Another downside to how the fan coil works are its performance in the summer. In this season, when cold water passes through the coils, due to the difference in temperature of the existing climate, water distillation occurs on the fan coils and dews are placed on the surface of the coils. This water, which is caused by distillation or condensation, is quite common but must be removed from the fan coil.
Failure to remove these small droplets can eventually cause problems due to the accumulation of droplets and the creation of a significant amount of water:
- Drainage and water leakage
- Damaging the colour of the room or even damaging the wall itself (in a wall fan coil)
- Corrosion and rust of non-resistant components inside the fan coil
- Creating a suitable environment for the growth of microorganisms
- Risks related to human safety and threat to human health due to the presence of microorganisms and their entry into the environment by air
- Decreased air quality entering the environment
- Create an unpleasant odour
These are things that can happen with the same water collected in the fan coil. As a result, this water must be removed from the fan coil and to remove it, gravity discharge method and drain pipe are used and it requires high supervision and accuracy in measuring the slope. You can also use the drain tray to collect this water and install it in the fan coil. In this way, water collects in the tray and then exits by a stream. In some types of fan coils, depending on the location and the surface or built-in installation, a pump is needed to drain the water in the tray. This pump is installed at the bottom of the tray and is connected to the drain pipes to direct the accumulated water to the disposal site. Thus, another disadvantage of the fan coil is the need for piping in it.
The relatively poor fan coil efficiency
Since the proper performance of the fan coil depends to a large extent on the filters, if the fan coil filters are not constantly cleaned and inspected, the useful performance of the fan coil will be questioned and its efficiency will be reduced. In this way, the quality of the air entering the environment is affected. Also, not cleaning the filters themselves will reduce their useful life and damage them sooner. Because fan coil filters are not of high quality and are not good enough to be counted on for a long time.
Inability to control humidity in the fan coil
In humid areas, the fan coil practically does not control and reduce humidity and needs to be supplemented by an air conditioner.
Disadvantages of fan coils related to the internal building and its structure
Another disadvantage of the fan coil that goes back to the building of the complex is the lack of channels in the fan coil and the use of pipes instead of channels. This situation becomes problematic when, if separation is required by the duct, the internal fan coil structure prevents it.
Disadvantages of fan coil related to its application
Because fan coils are used in places with multiple independent units, they also require a large number of components and equipment, which increases the likelihood of failure of all of this equipment. In addition, the fan coil itself has many components and many breakables in one unit, which requires high maintenance and regular service to have a long service life. Thus, with the high need for fan coil maintenance, supervision and repair, people have to service it annually or in a shorter period of time, depending on the fan coil activity in the hot and cold seasons of the year, and spend money and energy.
As a result, despite the simple fan coil system, one of its disadvantages is that its parts need to be constantly replaced and repaired, and this is costly. One of the most important parts of fan coil maintenance that causes many problems are the drain trays and filters, which must be constantly cleaned and checked. Because the filter directly affects the performance of the fans, and the fullness of the tray in this also reduces the efficiency of the fan coil and interferes with the entry of air.
