Fan coil unit
（重定向自Unit ventilator）
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 thermostat, this in turn controls the throughput of water to the heat exchanger using a control valve and/or the fan speed.