Fan convection or fan convection is a terminal installed directly in the conditioned space or in the plenum of the ceiling just above the conditioned space. The Retrofit fan coils unit contains a small motor-driven centrifugal fan or two small centrifugal fans connected in parallel with the finned tube filter and housings and external controls may sometimes have a cooling coil attached where a heating coil can be attached.
Airflow series as shown in the figure. The fan coil can be mounted horizontally on the block inside the ceiling, vertical devices are mounted on the floor under the windowsill (Fig.) or stacks are installed vertically on both sides of the window. The vertical and stacking units are usually used to balance the cold wind on the inner surface of the window pane or on the outside wall in cold weather.
Cold wind often flows under the glass because that's how it is heavier than the surrounding air. Warm air expelled by fans during winter heating increase the temperature of the inner surface of the glass.
Double width, double suction, and forward-curved centrifugal fans are generally used because of their characteristics of compact size and lower rate. Fan wheels are usually made of aluminum or galvanized Steel less than 10 inches (250mm) in diameter In most cases, the fan housing is stamped with built-in coil and input.
Constant Divided Capacitor (P$C) and Shaft Pole (SP) motors are used as in kit 26. PSC motors have an efficiency of 55 to 70 per cent, which is significantly higher than sp Motors with 30 to 40 percent efficiency.
