– 11 –
Temp. S0.9°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
NOTE
: Second stage heat is not utilized in Class 2 mode. Unless 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 lock out conditions. I2R lockout prohibits all resistance heating and will only allow
heat pump and boost heating. 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