Trane UV-SVN02B-EN, Installation Operation & Maintenance, Page: 7 / 52

General Information
UV-SVN002-EN 7
Unit Ventilator Controls
Controls are provided either by Trane as
a factory-mounted option or furnished
by an outside vendor and mounted at
the job-site.
Units constructed for field installation
of controls are shipped with one of the
following type of controls:
• No Controls/Field Installation:
(Option) The unit comes equipped
with an auto transformer, fan speed
switch and damper blade only.
• End Device Package (EDP):
This option pre-wires optional
control components to a terminal
strip for wiring field provided
controller and temperature sensor.
NOTE: For controller operation mal-
function of any non-Trane, field-
installed controls, consult the literature
or technical support of the controls
manufacturer.
Trane offers Direct Digital Controls for
the unit ventilator. The
ZN520 (See
Figure 2) unit controller is designed to
provide control of the classroom unit
ventilator and the fan coil products and
adds increased functionality to the unit
ventilator.
When Trane controls are ordered for an
installation, the controls are shipped
already installed and factory-tested to
ensure proper operation at start-up.
NOTE: For more details on the ZN520
unit controller option or operation and
service/replacement issues, please refer
to
CNT-SVX04A-EN : Tracer ZN520 Unit
Controller IOP.
Automatic Controls
Regardless of type of controls, all sys-
tems provide a sequence of operation
designed to provide rapid warm-up of
the room and increase ventilation while
offsetting overheating.
In addition, air conditioning installa-
tions will usually provide a means of
system changeover from heating to
cooling as well as provisions for draw-
ing a pre-determined amount of outside
air into the room.
Unit Switch
The unit “On-Off” switch, provided by
Trane, is typically housed in the control
box mounted in the left hand end pock-
et immediately below the discharge
grille.
When Trane ZN520 unit controllers are
used, the unit switch is located on the
switch module in the end pocket behind
the front panel rather than below the
grille.
Figure 2: ZN520 unit controller