Lennox Prodigy 2.0 Application Manual page 149

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
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