Diagnosis
This usually means the evaporator coils are frozen solid. When that happens, air can’t pass through properly to condense, so you just get cool, damp airflow. It’s common in cooler rooms.
How to Fix It
1) Turn the unit off and unplug it. 2) Move it to a warmer room if possible, or just let it sit off and thaw completely. This can take several hours—don’t rush it. 3) While it’s thawing, check and clean the air filter. It’s behind the front grille; just pull it out, rinse it under lukewarm water, let it dry fully, and put it back. A dirty filter restricts airflow and makes freezing more likely. 4) Once fully thawed, plug it back in and set it to a higher humidity target or ‘Continuous’ mode.
If That Didn't Work
If it freezes up again quickly in normal room temps (above 65°F), the refrigerant charge might be low or there could be a sensor issue. That’s a job for a certified appliance repair tech, as it involves sealed-system work.
Heads Up
Try to avoid running it in an unheated basement or garage when temps consistently drop below 65°F. These are ‘warm room’ dehumidifiers and aren’t designed for cold spaces.