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Heat Pump Operation
The Overheat Protection is only on the AZ6500 series.
The Overheat Protection system protects the Zoneline from overworking when the outdoor temperature 
is too high for heat pump operation.  The temperature of the indoor coil is monitored, and if it rises 
above 131°F, the control stops the outdoor fan.  The Zoneline will resume normal operation when the 
coil temperature is below 122°F.
Indoor Coil Overheat Protection
  Indoor Coil Overheat Protection
Indoor Coil 
Temperature
131°F
122°F
Outdoor Fan
Compressor
ON
ON