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Aprilaire Service Manuals & Error Codes
38Service Manuals
9Error Codes
1Appliance Types
Aprilaire Appliance Types
MyPros+ Max
Every Aprilaire service manual. One app.
- Step-by-step diagnostic procedures with test values from the service manual
- Wiring diagrams, parts diagrams, and connector pinouts
- Verified part numbers when replacement is required
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Top Error Codes for Aprilaire
CodeTypeDescription
E1HVACInternal RH/Temperature Sensor open or shorted — the User Interface Assembly is...E2HVACHigh Refrigeration Pressure: The temperature of the discharge line exceeds...E3HVACModel 76 Remote Control Communication Loss: A Model 76 control wired to the...E4HVACInsufficient Capacity: The suction line temperature has not dropped at least...E5HVACHigh Temperature Sensor Thermistor Failure — the signal from the High...E6HVACLow Temperature Sensor (Frost Sensor) Thermistor Failure — the signal from the...E7HVACFloat Switch Open: The Float Switch input to the User Interface Assembly is...E8HVACInlet Air Temperature Out of Range: The incoming air temperature is less than...E9HVACOutdoor Temperature Sensor Failure: The signal from the Outdoor Temperature...