Usually the supply air temperature in overhead distribution system is about 52-55°F which after removing the space heat, the room temperature will be raised to the 72-74°F to meet the comfort temperature and condition for the people. In this case the room temperature close to the overhead supply air diffusers are about the supply air temperature (52-55°F) but for the raised floor air distribution system this temperature is too low for people and need to be higher than 55°F otherwise people feel cold. The best supply air temperature for the raised floor air distribution system is around the 65-68°F but need to supply more air flow (CFM) to the room than the overhead supply air distribution system to meet the comfort zone.
