Dehumidifier not collecting water

How a dehumidifier pulls water from the air

A dehumidifier works like a small air conditioner. A compressor pumps refrigerant through a cold coil behind the front filter. A fan pulls room air through the filter and across that cold coil, and moisture in the air condenses on it, the way a cold glass sweats. The water drips into a pan and then into the bucket, or out through a hose. The air then passes a warm coil and leaves the unit slightly warmer and drier than it came in.

It only makes water when three things are true: the air has more moisture than your setting, the coil is cold but not frozen, and air can move across it. A setting at or above the room's humidity tells the unit to idle. A room below about 65°F makes the coil frost over, and many units then switch to a defrost cycle that collects little. A clogged filter starves the coil of air, which also leads to frost. If the compressor itself has failed or lost refrigerant, the coil never gets cold and the unit just blows air.

Why the bucket stays empty

Let's fix it

1. Check the humidity settingLook at the display. Many units show the current room humidity and your target. If the room reads 45% and the target is 50%, the unit won't collect anything, because the job is done. Most homes do well around 30% to 50% humidity. To test the unit, set it to its lowest setting or to Continuous, run it for an hour or two with doors and windows closed, and check the bucket. A cheap separate hygrometer helps confirm the reading, since built-in sensors can be off by several percent.
   Done

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2. Warm the room or use the right unitCheck the room temperature with a thermometer. Many standard dehumidifiers work poorly below about 65°F and frost up at lower temperatures, which is common in basements in spring and fall. Check your manual for its lowest operating temperature. If the room is cool, raise the temperature a little if you can, or run the unit during the warmest part of the day. Some models have a low-temperature or auto-defrost mode. For a consistently cold basement or crawl space, a unit rated for low temperatures, often a larger basement model, does much better.
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3. Clean the filterUnplug the unit. Slide out the filter, usually behind the front or back grille or above the bucket. Hold it to the light. If it's dusty, vacuum it gently or rinse it under lukewarm water and let it dry completely before putting it back; don't use a dishwasher or hot water, which can warp it. Most manufacturers suggest cleaning the filter every two weeks or so during heavy use. Never run the unit without a filter, since dust coats the coil and is much harder to clean.
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4. Thaw an iced coilWith the filter out, shine a flashlight on the coil behind it. A thin layer of frost or solid ice means the coil froze, often from a cool room or a clogged filter. Turn the unit off, unplug it, and let the ice melt on its own, usually a few hours. You can speed it up by running the unit on fan only, if it has that setting, or setting it in a warmer room. Put a towel under it for the meltwater. Don't use a hair dryer up close or pick at the ice. If it ices again soon in a warm room with a clean filter, the unit may be low on refrigerant.
   Done

   Something went wrong?

   • It ices up every day Move it to a warmer spot or raise the room temperature, keep the filter clean, and make sure nothing blocks the air intake or outlet. If it still ices above about 65°F, it needs a technician or replacement.

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5. Check the bucket and drain hoseIf a hose is connected to the drain outlet, water goes out through it, so look where the hose ends and whether water is coming out. Make sure the hose runs downhill the whole way, with no kinks or loops that trap water; most units drain by gravity unless they have a built-in pump. If you use the bucket, check that it's seated all the way, since many units stop or don't collect when the bucket's float switch thinks it's full or missing. Empty the bucket, check that its float moves freely, and slide it back until it clicks. A Bucket Full light with an empty bucket usually means a stuck float.
   Done

   Something went wrong?

   • Bucket Full light with an empty bucket Clean the float and push the bucket in firmly. If the light stays on, the bucket switch may need replacing.

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6. Check that the compressor runsPut the filter back, plug the unit in, set it to its lowest humidity setting, and give it a few minutes; many units delay the compressor for about 3 minutes after starting. Then listen and feel. A working unit has two sounds, the fan and a lower hum from the compressor, and the air coming out feels a few degrees warmer than the room. The coil behind the filter should feel cool after 10 to 15 minutes. If only the fan runs and the air isn't warmer, the compressor isn't running, or the unit has lost refrigerant. For a portable unit, that's usually the end of its life; check the warranty, since many cover the sealed system longer than the rest.
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Watch it done

How Fix ANY Dehumidifier that Runs but Does NOT Collect Water: Troubleshooting Tips (Weird Sound)By Helping Hermit on YouTube. Their method may vary a little from ours.

Watch on YouTube

If it comes back

If the room keeps getting damp even with the unit working, the moisture source needs attention. A musty basement often has water coming in from outside; see the guide for a musty basement smell and the guide for water pooling near the foundation.

If windows fog up inside in cold weather, humidity is too high in the house. See the guide for condensation on windows.

If one room is much warmer or cooler than the rest of the house, it can also feel damp. See the guide for a room that's too hot or cold.