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critical Trane

Error Code E09

Shorted pressure switch open, pressure switch open, thermal limit, rollout switch or reverse airflow, flame detected but should not be present.

? What Causes This

Failed switches, clogged air intakes, improper positioning of components.

How to Fix It

Check and replace faulty switches if found. Clean intake lines and vents. Verify proper installation procedures were followed.

Source: page 26 of the official manual

From the manual

Manual page 26 — Trane error E09

This error code appears in:

Trane S9x1