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error Aprilaire

Error Code Solid red Fill light

Fill valve has been energized for over 40 minutes without successful water detection or low spot in steam hose.

? What Causes This

High static pressure, obstruction, or improper installation of the steam hose.

How to Fix It

  1. Verify high water probe connection is tight and secure on canister top.
  2. Ensure steam hose has appropriate slope from dispersion tube to humidifier without any dips.
  3. Check all tee connections for proper functioning, ensuring no backpressure issues in system.

Source: page 27 of the official manual

From the manual

Manual page 27 — Aprilaire error Solid red Fill light

This error code appears in:

Aprilaire 800