Tracer Zn520 Operation - Trane UniTrane Installation, Operation And Maintenance Instructions

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.

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.
UNT-SVX07B-EN
Start-Up
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