Blower coil

A Fan Coil Unit (FCU) is a simple device consisting of a heating and/or cooling heat exchanger or 'coil' and fan. It is part of an HVAC system found in residential, commercial, and industrial buildings. A fan coil unit is a diverse device sometimes using ductwork, and is used to control the temperature in the space where it is installed, or serve multiple spaces. It is controlled either by a manual on/off switch or by a thermostat, which controls the throughput of water to the heat exchanger using a control valve and/or the fan speed.

Due to their simplicity and flexibility, fan coil units can be more economical to install than ducted 100% fresh air systems (VAV) or central heating systems with air handling units or chilled beams. Various unit configurations are available, including horizontal (ceiling mounted) or vertical (floor mounted).

Noise output from FCUs, like any other form of air conditioning, is principally due to the design of the unit and the building materials around it. A correctly selected FCU, like some of those from the UK, can offer noise levels as low as NR25 or NC25

The output from an FCU can be established by looking at the temperature of the air entering the unit and the temperature of the air leaving the unit, coupled with the volume of air being moved through the unit. This is a simplistic statement, and there is further reading on sensible heat ratios and the specific heat capacity of air, both of which have an effect on thermal performance..

Firstly, it should be noted that 'Fan Coil Unit' is a generic term that is applied to a range of products. Also, the term 'Fan Coil Unit' will mean different things to users, specifiers, and installers in different countries and regions, particularly in relation to product size and output capability.

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Wikipedia