Skip to main contentSearch any Aprilaire model number
Aprilaire Service Manuals & Error Codes
36Service Documents
3Service Manuals
16Error Codes
11Appliance Types
Aprilaire Appliance Types
HVAC
12 service documents9 error codes
Air Conditioner7 service documents
Dryer4 service documents
Dehumidifier3 service documents
Microwave1 service document
Freezer1 service document
Oven1 service document
Refrigerator1 service document
Furnace1 service document7 error codes
Washer1 service document
DishwasherMyPros+ 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
Get Started
$29/month · Cancel anytime · Or $9.95 3-day pass · Plus applicable tax
Top Error Codes for Aprilaire
CodeTypeDescription
1 FlashFurnaceSystem lockout - flame was not sensed during ignition attempts and the control...2 FlashesFurnacePressure switch stuck closed - the control senses the pressure switch is closed...3 FlashesFurnacePressure switch stuck open - after the vent blower is energized, the pressure...4 FlashesFurnaceOpen limit control - the limit control has opened due to excessive temperature.5 FlashesFurnaceMissing jumper wire - the jumper between R01 and R02 on the control is not...Continuous FlashingFurnaceFlame sensed with no call for heat - the control senses a flame when the gas...Continuous LightFurnaceInternal control failure - the WR50A50 control has determined it has an...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...