How Do Fan Coil Units Work?

A fan in a fan coil unit (FCU) pulls air from a room into the device and distributes it over a cooling or heating coil. Either colder or hotter air is released from the FCU than before. They are frequently mentioned where there are numerous small spaces that need individual control and are used in some workplace buildings and shopping malls. FCUs are typically added to buildings where the bulk of the air conditioning is provided by other HVAC systems.

A chilled water coil for chilling and either a hot water coil for heating or an electric heating element are typically found in FCUs. A chiller in the central facility provides chilled water, and a boiler produces hot water.

FCU systems are efficient, and with proper upkeep and operation, they are capable of producing high levels of efficiency. They are typically less effective than common substitutes like displacement systems, chilled beams, and variable volume air cooling.

The fan coil unit's operations are controlled by a thermostat. Air from the interior is drawn into the device by a fan. Some systems also permit the addition of outside oxygen. The inbound air travels across the coil of the device after passing through a filter. The coil moves refrigerant or hot or cold water to warm or cool the air. Some appliances heat air using electric heat bands. The fan forces the conditioned air from the system back into the interior area.

 

FCU & AHU

 

The ventilation system contains both an AHU and an FCU. AHU, also referred to as an air handling unit, differs from a fan coil unit (FCU).

An FCU can operate or be placed on its own, whereas AHUs are typically connected to a central HVAC system. As a result, the AHU is frequently used to ventilate an entire building, whereas FCUs are typically only used in smaller, more localised areas. It should come as no surprise that the AHU is the larger HVAC system and that the FCU is also thought of as the AHU's lesser sibling. The tiny FCUs can be referred to as terminal units in this context.

The size of the AHU system dictates that it frequently uses air from the outside world. As a result, it purifies outdoor air and uses special ducts to transport it inside the area, whereas an FCU system simply circulates indoor air. The latter is typically devoid of a duct system, which accounts for its smaller size. It is only made up of a fan and a coil.

AHUs typically have some characteristics that the FCU does not have. AHUs have a number of areas for humidifying and even reheating. Such parts are absent from FCUs.

Multiple fans or blowers may be placed in an AHU's system. The blowers for the AHU are typically installed at the beginning of the ducts or at the conclusion of the air handler unit. FCUs handle blowers differently. Their fans are typically installed in the same area as the device itself due to its small size. The end product is a mildly unsettling noise that is audible nearby. The FCU system's one greatest strength could be considered to be this.

To know more, visit Edgetech’s Product Page to get the best of our AHRI Certified Portfolio products.