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⚠
warning Rheem

Error Code Error Code 90

Air intake or vent exhaust opening may be blocked.

? What Causes This

Ventilation openings are obstructed by debris, dirt, leaves, or other materials preventing proper airflow.

✓ How to Fix It

  1. Turn off the unit.
  2. Inspect the air intake and vent exhaust openings.
  3. Remove any visible obstructions.
  4. Clear debris from around the unit.
  5. Restart the unit and verify normal operation.

This error code appears in:

Rheem Tankless Water Heater