E12 — Airflow Restriction / Vent Blockage (Vented Models)

How to fix it

1. Disconnect the transition duct at the back of the dryer.
2. Run a short test cycle — if E12 clears, the restriction is downstream.
3. Inspect the transition duct from dryer to wall — replace with smooth rigid metal if it's foil or plastic.
4. Inspect the exterior vent hood — clean out lint, leaves, and any nests; verify the damper flap moves freely.
5. Have the vent run professionally cleaned if it exceeds 10 feet or has multiple elbows.
6. Measure vent run length and elbow count; reroute if it exceeds code limits.
7. Reconnect transition duct, ensuring no kinks, and run a full cycle to verify normal drying time.

Why it happens

Typical signs: Cycle takes much longer than normal · Clothes hot but still damp · Dryer cabinet hot to touch · Lint accumulating around door seal

• Blocked exterior vent hood Bird nest, lint buildup, or closed louvers at exterior wall vent.
• Crushed or kinked transition duct Foil/plastic transition hose pinched behind dryer.
• Lint buildup in vent run Long vent runs accumulate lint over years and need professional cleaning.
• Plastic/foil transition duct (code violation) Combustible flexible duct should be replaced with smooth-wall rigid metal.
• Vent run too long or too many bends Code limit typically 25 feet minus 5 feet per 90-degree elbow.

Parts you may need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

• Rigid metal dryer transition duct Common replacement
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• Dryer vent cleaning brush kit Common replacement
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