Error code reference

Aprilaire HVAC Error Codes

9 error codes documented with diagnostic procedures.

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E1Internal RH/Temperature Sensor open or shorted E2High Refrigeration Pressure E3Model 76 Remote Control Communication Loss E4Insufficient Capacity E5High Temperature Sensor Thermistor Failure E6Low Temperature Sensor (Frost Sensor) Thermistor Failure E7Float Switch Open E8Inlet Air Temperature Out of Range E9Outdoor Temperature Sensor Failure

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More Aprilaire error codes