Error code reference

Aprilaire HVAC Error Code E2

High Refrigeration Pressure: The temperature of the discharge line exceeds 190°F. Self-correcting unless it occurs for five consecutive compressor starts, usually caused by inlet air temperature too high (>100°F) or very low airflow through the dehumidifier.

SourceAprilaire Dehumidifier - Service Manual: Models 1830, 1850, 1870p. 3

Aprilaire codes Aprilaire hvac codes

Diagnostic procedure

The full E2 procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Turn the ON/OFF toggle switch OFF to reset the diagnostic code, then check if the fan is working and inspect ductwork connections.

SourceAprilaire Dehumidifier - Service Manual: Models 1830, 1850, 1870p. 3

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More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

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Where this code is documented

3 manuals in the MyPros+ library document this code for Aprilaire hvac.

Models covered by the manuals that document this code

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The full E2 procedure

Where this code is documented

Models covered by the manuals that document this code

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