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NOTE: The second stage heat is not utilized in Class 2 mode.  Unless the Auxiliary Set (or Aux Set) 
"boost heat" is selected.  Stage 2 heating will operate when the thermostat calls for Stage 1 heating.
•  THIRD STAGE HEAT (HEATERS A AND B ONLY)
When the room temperature falls below 2.7°F from the temperature control setpoint, the heat pump 
operation will stop.  Stage 3 heating is activated (based on power cord) for all outdoor temperatures, 
except for l2R lockout conditions.  Stage 3 will continue to operate until the room temperature 
exceeds the temperature control setpoint by 0.9°F at which time the heaters will shut down.
Stage Heating Mode Logic for AZ6500 Series
Temp. Setting +0.9°F
Heater B
Heater A
Compressor
Temp. Setting -2.7°F
Temp. Setting -1.8°F
Room Temp.
Temp. Setting
ON
ON
ON
ON
ON