Fan Coil Unit FAQs
Whether you’re wondering what an FCU, or fan coil unit is or even how they work, our FAQs aims to answer your questions about FCU air conditioning systems.
What is a Fan Coil Unit?
A fan coil unit is a unit such as an air conditioning unit, with one or several fans inside as well as a heat exchanger coil inside, which provides a room with cooled or heated air.
How does a Fan Coil Unit work?
The fan, or fans, pull or blow air through the unit and across the coil. Chilled or heated water piped from a chiller, heat pump or boiler passes through the coil, adjusting the air temperature supplied to the room. The air in the room is then recirculated through the FCU to achieve the desired room condition.
Types of FCU
FCUs either operate with water, known as 2 or 4 pipe fan coil units, or with refrigerant gasses known as VRF or DX units. Both styles are then made in either in a horizontal or vertical position which is defined by the direction of airflow and can come in chassis (no casing) or cased units.
What is SFP relating to Fan Coil Units?
SFP stands for Specific Fan Power and is a ratio of the energy used by the units fans to provide the FCU airflow. Watts / Litres of Air per Second (W/L/S).
Why is “BS8850: 2020 Fan coil unit performance – Determination of specific fan power” important to consider?
It sets a method of testing for FCUs to provide SFP data that can be fairly compared between manufacturers. Assisting in the transparency of energy efficient equipment.
How Big Are Fan Coil Units?
Typically, fan coil units are around 500 – 2,000mm wide and between 160 – 400 mm deep. The typical length is 500 – 800 mm.
Do all Fan Coil Units need Attenuators?
No! However they do offer greater flexibility in providing an optimised FCU selection and are likely required when you wish to offer noise levels at a noise criterion of NR30 or quieter.
Can I design my Office without a false ceiling?
Yes, however false ceilings are often an acoustic barrier to fan coil unit noise. If removed, special consideration should be given to the required noise criterion in the occupied space.
How much do Fan Coil Units Cost?
The average cost per unit is around £750 – without considering any ancillaries like controls, attenuators or valves etc.
Why Are Air Conditioning Units called Fan Coil Units?
A local air conditioning unit which uses a fan to move tempered air, which is provided by a coil, is then commonly referred to as a fan coil unit.
What is Sensible, Latent and Total Cooling?
Sensible is the cooling that is delivered to the room, latent is the wasted energy the coil produces in the form of condensation. Total cooling is the combination of the sensible and the latent, with any reduction in latent cooling saving energy.
Correct Way To Refer to FCU?
There is no need to repeat the word unit as FCU stands for Fan Coil Unit.