SERIES FAN-POWERED TERMINAL UNIT FDC
FDC
The basic unit consists of a motorized damper, flow sensor, motorized fan, and associated control equipment at the conditioned (primary) air inlet. As accessories; heating units (water or electric type), filters, and silencers for use at the inlet and/or outlet can be supplied.
Operating Principle
According to the signal received from the thermostat, the control device transmits a signal to the damper motor on the conditioned (primary) air inlet, and with this signal, the actuator motor changes the damper's opening position to ensure the required amount of cooling air enters the unit. The fan inside the unit mixes a certain amount of cooling air with the warm return air drawn from the space into the false ceiling and then into the unit, and delivers it to the space through diffusers. As the primary (cooling) air increases or decreases, the return (recirculation) air ratio changes inversely, and the fan always operates at a constant flow rate. When the heating requirement of the space increases, the primary air quantity decreases to a minimum, and after a while, the heater activates. As a result, while the central system provides variable flow distribution, the terminal unit always ensures a constant airflow to the relevant space.
General Applications
Used in outer zones where heating and cooling requirements can vary significantly over time, where the central system needs to be shut down or temperature maintained at a certain level when spaces are unoccupied. It is also used when economic operation is desired in the central system, and most importantly, in spaces requiring constant airflow and where comfort with homogeneous air distribution is important.
