In each terminal unit, this primary air is discharged
in such a way that it draws in a much larger volume of
secondary air from the room, which is filtered and passed
through a coil for additional heating or cooling (Figure
10.11). The use of primary air as the motive force eliminates
the need for a fan in the induction unit. The cooling
coil is often deliberately kept at a temperature
greater than the dew point temperature of the room air
which passes through it, eliminating the need for a condensate
drain. Although the standard air-water induction
system is a cooling-only system, room terminals can
employ reheat coils to heat perimeter zones.