158
RT6
Discharge air temperature sensor
RT16
Return air temperature sensor
RT17
Outdoor air temperature sensor
SMK
Smoke detection mode (alarm)
SP
Setpoint
Stg
Stage
TB
Terminal block
UnOCP Unoccupied
W1
Thermostat demand, heat stage 1
W2
Thermostat demand, heat stage 2
W3
Thermostat demand, heat stage 3
W4
Thermostat demand, heat stage 4
VAC
Alternating current voltage
VAV
Variable air volume. Accomplished with a variable frequency drive (VFD)
VDC
Direct current voltage
VFD
Var. frequency drive. An AC inverter used to vary motor speed
VT
Ventilation
Y1
Thermostat demand, cooling stage one
Y2
Thermostat demand, cooling stage two
Y3
Thermostat demand, cooling stage three
Y4
Thermostat demand, cooling stage four
ZAT
Zone air temperature