Trane UniTrane FC, Installation & Operation Manual

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50 UNT-SVX07A-EN
Fan Mode Switch Operation
Off
Fan is turned off, two-position damper
option spring-returns closed.
Hi, Med, Lo
Fan runs continuously at the selected
speed. The two-position damper option
opens to an adjustable mechanical stop
position.
Tracer ZN010 & ZN510
Operation
Off
Fan is off; control valves and fresh air
damper option close. Low air
temperature detection option is still
active.
Auto (Fan Cycling)
Fan and fresh air damper cycle with
control valve option to maintain setpoint
temperature. In cooling mode, the fan
cycles from off to medium and in heating
mode it cycles from off to low. When no
heating or cooling is required, the fan is
off and the fresh air damper option
closes.
Low/Med/High (Continuous Fan)
Fan operates continuously while control
valve option cycles to maintain setpoint
temperature. Fresh air damper option is
open.
Operation
sequence of
operation
Tracer ZN520 Operation
Off
Fan is off; control valve options and fresh
air damper options close. The low air
temperature detection option is still
active.
Auto
Fan speed control in the auto setting
allows the modulating (3-wire floating
point) or 2–position control valve option
and three-speed fan to work
cooperatively to meet precise capacity
requirement, while minimizing fan speed
(motor/energy/acoustics ) and valve
position (pump energy, chilled water
reset ). As the capacity requirement
increases at low fan speed, the water
valve opens. When the low fan speed
capacity switch point is reached, the fan
switches to medium speed and the water
valve repositions to maintain an
equivalent capacity. The reverse
sequence takes place with a decrease in
required capacity.
Low/Med/High
The fan runs continuously at the selected
speed and the valve option will cycle to
meet setpoint.