Fan-coil unit – How does it work and where is it used?

A fan coil is a versatile cooling and heating device consisting of a finned heat exchanger and a fan. Its function is to circulate the room air through the heat exchanger , which uses a hot or cold heat medium , thus ensuring the temperature of the room.


How does a fan coil unit work?

Heat exchanger: A cold or hot coolant (e.g. water) flows through the fan coil heat exchanger. The fins of the heat exchanger help transfer heat between the coolant and the air.

Fan: The fan circulates the room air through the heat exchanger.
The air passes through the heat exchanger, cools or heats up, and then returns to the room.

Cooling and heating:

  • Cooling: The refrigerant delivers cold water to the heat exchanger, which cools the air.
  • Heating: The refrigerant transports hot water to the heat exchanger, which heats the air.

Control: Fan coil units can be controlled by a thermostat, which regulates the fan speed and the amount of refrigerant flowing through the heat exchanger.

Types of fan coil systems

By placement:

  • Floor-standing (parapet): Ideal for existing rooms, easily accessible for maintenance.
  • Can be built into a false ceiling: An aesthetic solution that remains hidden in the interior space.
  • Wall mountable: Compact solution for tight spaces.
  • Visible or hidden design: Can be chosen according to aesthetic and functional needs.

By number of tubes:

  • Two-pipe system: A single refrigerant circuit that can be used for either cooling or heating.
  • Four-pipe system: Separate circuits for cooling and heating that can operate in parallel.

Advantages of fan-coil systems


Cooling and heating in one system: A single unit can meet both cooling and heating needs, reducing equipment and installation costs.

Compact design: No need for separate radiators and air conditioners, which means a space-saving solution.

Energy efficiency: Fan-coil systems powered by a heat pump or central boiler can be more economical than traditional heating and cooling systems.

Easy installation: Multiple placement options allow for easy integration into existing systems.

Controllability: Individual temperature control is available in each room, increasing comfort and energy efficiency.

Cost-effectiveness: Investment and maintenance costs can be lower compared to a combination of separate systems.

Maintenance and operation

Cleaning air filters: Regular cleaning of dust and dirt deposited on the filter of the air circulated by the fan is necessary to maintain efficiency and air quality.

Heat exchanger maintenance: Dust and dirt deposited on the heat exchanger fins reduces heat transfer, therefore periodic cleaning is necessary.

Fan maintenance: The moving parts of the fan need to be checked and lubricated to ensure proper operation.

Check water supply and pipes: It is essential to check the pipes and valves that provide the refrigerant supply for leaks and their condition.

Summary


The fan coil unit is an efficient and cost-effective solution for cooling and heating systems, combining both functions in a single unit. Flexible placement options and easy control make it ideal for both residential and commercial applications. With regular maintenance, fan coil units provide long-term, reliable operation, contributing to the energy efficiency of buildings and indoor comfort.