Run a Vent Blockage test on your Samsung dryer

A person checking  the Samsung dryer duct

The Vent Blockage test on your dryer automatically detects the status of the exhaust ducts and reports any blockages or problems. You should run one of these tests after the dryer is initially installed, and every once in a while after that. Clean, proper ducting can help reduce drying time and save energy as well.

Note: Not all dryer models have a Vent Blockage test. Check your user manual to confirm.

Run a Vent Blockage test

Note: Even if your dryer passes the test, you should still clean your exhaust vent once or twice a year.

If you used your dryer prior to starting the test, it may not enter the test mode; your dryer must be sufficiently cooled down first. If you’re running the test right after installing your dryer, you can run the AIR FLUFF cycle for several minutes to reduce the internal temperature.

  1. When you're ready to start, make sure the drum is empty and then close the door. If there is any laundry in the drum, the test will not give accurate results.

  2. Press POWER to turn the dryer on and within 5 seconds, press and hold Adjust Time Up + Dry Level until InS or In appears on the display.

    Demonstration of which two buttons to press and how InS will appear on the display

    If that button combination does not work, here are other combinations you can try:

    • Cycle 1 + Wrinkle Prevent

    • Air Fluff + Wrinkle Prevent

  3. Press and hold START/PAUSE to start the Vent Blockage test which lasts for approximately 2 minutes. Do not open the door during the test.

  4. Once the test is complete, the results will be displayed:

    Result for the Vent Blockage Test:

    • 0 or End: The duct system is normal and unblocked.

    • CLg, Cg, CL9, C9, C80, C8, C90: The duct system cannot exhaust properly. A code like C8 or C80 indicates about 80% clogged, a code like C90 or C9 indicates about 90% clogged. You will need to clean your dryer's exhaust vent.

    • dc: The door is open. It must be closed to run the test.

    • C1 or CL1: Laundry is detected inside the drum. The drum must be empty to run the test.

    • Ct: The internal temperature of the dryer is too low (below freezing) or too high (above 104°F) to perform the test. Wait for the dryer to resume room temperature and perform the test then.

  5. The results remain on the display for about 5 minutes. Press POWER to turn off the dryer, or wait for it to turn off automatically after the 5 minutes have passed.

Check for vent blockage on models without the test

Caution: Some older models do not reduce heat when a vent is clogged and so this test is not effective on them. If you encounter long cycle times, though, even when the dryer is plenty hot, the cause is still most likely to be a clogged vent, and in that situation you are most at risk for a fire in your vent since the dryer is not reducing its heat. This is one of the reasons it's important to clean your exhaust vent once or twice a year even if your dryer passes this test, and especially whenever cycle times are running longer than they have in the past. It's also why newer models reduce the heat when a blockage is detected, and you can get your dryer heating properly again by cleaning your vent.

For most models without a vent blockage test, the way to check if your vent is causing a low heat issue is to see if your dryer's heater performs better when the vent is disconnected.

  1. Disconnect the exhaust vent from the dryer.

  2. Run a Time Dry cycle for at least 30 seconds. (Make sure the Eco Dry setting is turned off, if your model has it.)

  3. Feel for hot air inside the drum.

What you do next depends on whether the dryer is hotter without the vent than it was when the vent was connected:

  • If the dryer is hotter when the vent is disconnected, then either your exhaust vent is too clogged and needs cleaning, or your vent doesn't meet the requirements set in the user manual to provide enough airflow for the dryer.

  • If you feel the same amount of hot air either way, then your vent is not causing your dryer to reduce heat.

  • If you feel no hot air at all when performing this test, see our Dryer has no heat at all article for troubleshooting.

samsung logo action minus
Contact us
We're here for you.
We're here for you

Contact Samsung Support

Contact us online through chat and get support from an expert on your computer, mobile device or tablet. Support is also available on your mobile device through the Samsung Members App.
Table of contents