Trane LO - Manual (Page 95)

UNT-IOM-6 95
Terminal Unit
Control (TUC)
Note: The auxiliary electric heat option is not available with a four-pipe
fan-coil unit.
Units with manual fresh air
dampers ship with the damper in
the closed position, which is
adjustable from zero to 100
percent in 25 percent incre-
ments. To adjust the position,
first remove the air filter to
expose the damper stop screw
on the control panel end. Relo-
cate the stop screw to the
appropriate position. Then loosen
the stop screw wingnut and
adjust the linkage. See Figure
30.
Units with an auto 2-position fresh air damper ship with a stop screw
in the 25 percent reference position. The auto damper is adjustable to
open from zero to 50 percent in 25 percent increments. To adjust the
damper position, remove the air filter to expose the damper stop
screw on the control panel end. Then relocate the stop screw to the
appropriate position. See Figure 30.
Note: The open position of the damper does not correspond to the
amount of fresh air. It is the installer’s responsibility to ensure that
the building’s minimum fresh air requirements are met while taking
necessary precautions to protect the unit during freeze conditions.
The economizer damper option contains a modulating, 3-wire floating
point actuator and a damper assembly. The factory sets the damper
at a minimum 25 percent open position by configuring the TUC. This
setting is adjustable and can be changed in the field with EveryWareä
software or Tracer â . The minimum open position is adjustable from
zero to 100 percent in one percent increments.
The economizer fresh air damper is controlled to the minimum
position, which the factory configures. During the occupied mode,
economizing is enabled and the fresh air temperature is measured
while economizing.
Economizing is enabled within the TUC configuration based on an
editable temperature differential between the fresh air temperature and
the zone temperature. The unit will go into economizing mode when
Fresh Air Damper
Options
Auto 2-Position
Economizer
Figure 30. Re-locate the damper
stop screw to adjust the damper
position. The factory positions
the stop screw in the 25% open
position.
Manual