Your Dehumidifier Ices Up? (Discover the Causes & how to Fix it)

If you’ve walked into your basement or laundry room and noticed your dehumidifier covered in a layer of ice, you’re not alone. It can be confusing at first—especially when you’ve just bought the unit or it was working fine a week ago. Now it’s humming loudly, barely collecting any water, and you’re left wondering if it’s broken or if there’s something you missed.

Here’s the truth: a dehumidifier freezing up is a common issue, especially in cooler or poorly ventilated spaces. But that doesn’t mean you should ignore it. Ice build-up doesn’t just reduce performance—it can quietly damage internal components over time, and if left unchecked, it might completely ruin your unit.

In this article, I’ll help you understand why it happens, how to fix it, and how to stop it from happening again—without all the technical fluff. We’ll also walk through brand-specific tips if you’re using Frigidaire, Midea, Hisense, or a portable model because not all units behave the same way when it comes to freezing.

Let’s break it down.

Why Is Your Dehumidifier Icing Up?

Your dehumidifier is designed to pull moisture out of the air using cold evaporator coils. As warm air is drawn in by a fan, it passes over these cold coils, which condense the water vapor. That condensed moisture is then collected in a tank or pumped out through a drain hose.

But when temperatures around the coils get too low, or airflow inside the unit gets blocked, that condensation turns into frost or ice instead of draining away.

And that’s when the trouble begins.

You’ll likely notice:

• Ice forming along the front or bottom edge of the unit

• A barely filled water tank even after hours of running

• Air that feels unusually cool is blowing out of the vents

• Strange noises like clicking, which can come from frozen fan blades or expanding parts

If you see any of this, chances are the evaporator coils inside are frozen, and your dehumidifier is not working effectively.

Is It Normal for a Dehumidifier to Ice Over?

In short—sometimes, yes. But only in specific conditions.

If your dehumidifier is in a cold room (under 60°F or 15.5°C) like a basement in winter or a drafty laundry area, some icing might happen during regular use, especially if the unit wasn’t designed to operate in low temperatures.

Most consumer-grade dehumidifiers aren’t made for cold spaces. They’re rated for room temperatures between 65°F–85°F (18°C–29°C). So if your basement regularly dips below 60°F, the unit is essentially being forced to run in a condition it wasn’t built for. Ice becomes a natural side effect.

That said, if your space is warm and the coils still freeze, or the icing happens quickly and repeatedly, it’s not normal—and it’s usually a sign of poor airflow, a sensor problem, or clogged internal parts.

Common Reasons Why Dehumidifiers Freeze Up

Let’s talk about the actual causes. These are the most common issues we’ve found both in customer service logs and hands-on troubleshooting.

✅ Cold Room Temperature

This is by far the most common culprit. If the ambient temperature is too low, the evaporator coils inside your dehumidifier will cool the air below freezing. Once the moisture in the air hits those coils, it freezes into solid ice instead of condensing into droplets.

Think of it like your car windshield on a chilly morning—it doesn’t matter how good your wipers are if the whole thing is iced over.

If you’re running your dehumidifier in an area where the temperature falls under 60°F, especially overnight, expect icing issues unless the unit is rated for low-temperature operation or has a built-in auto-defrost feature.

✅ Blocked or Dirty Air Filter

Your dehumidifier needs clean airflow to function properly. If the air filter is clogged with dust, pet hair, or general debris, it restricts the flow. When air can’t move freely over the coils, they can become too cold too fast—leading to ice formation.

Most filters are simple foam or mesh screens that slide out from the back or side of the unit. You’d be surprised how many of them get completely coated in gray dust just after a month of use—especially in homes with pets, heavy foot traffic, or laundry activity nearby.

Tip: Mark your calendar to clean the filter every 3–4 weeks. Just rinse it with warm water and let it dry before sliding it back in.

✅ The Fan Motor Isn’t Working Properly

If your fan is spinning slowly, not spinning at all, or making inconsistent sounds, that’s a major red flag. Without proper airflow, the unit can’t move warm air across the cold coils, and those coils will stay too cold for too long—causing them to ice over.

A failing fan motor can also lead to poor moisture removal overall. In some cases, the fan might run fine at startup, then slow down as the motor heats up. That’s something you’ll only catch if you pay attention after the unit has been running for a while.

If you suspect a fan issue, unplug the unit and try spinning the fan blades manually (if you can access them). They should move easily and without resistance.

✅ Faulty Humidistat or Sensor Malfunction

The humidistat tells the dehumidifier when to turn on or off based on room humidity. If this component is broken or misreads the air’s moisture level, it might run the compressor continuously, even when unnecessary.

Running constantly means the coils stay cold, and if airflow is even slightly restricted—bam, ice.

We’ve seen this, especially with older Hisense and GE units where the control board misreads the humidity level and forces the machine to run longer than it should.

✅ Improper Placement (Too Close to Walls or Furniture)

Your dehumidifier needs room to breathe. If it’s placed too close to a wall, corner, bed, cabinet, or couch, it can’t pull in or exhaust air properly. That trapped air creates microclimates inside the unit, especially around the coils, leading to—you guessed it—icing.

Best practice: Keep your dehumidifier at least 12 inches away from any wall or obstruction. It should feel like it’s sitting in the open air, not squeezed into a tight spot.

✅ Dirty or Blocked Coils

If your dehumidifier has been in use for several seasons—or you bought it secondhand—the evaporator coils could be covered in grime or mold. Dirty coils struggle to transfer heat efficiently, and they tend to build up condensation faster than they can get rid of it.

Over time, that moisture sits on the coil surface, cools, and eventually freezes.

Use a soft brush or compressed air to clean coils gently. Do not scrape them or use metal tools—they’re delicate and damage easily.

How to Fix a Dehumidifier That’s Freezing Up

Once you’ve identified that your dehumidifier is icing up, it’s time to act. You don’t always need a new unit or a technician. Often, a few thoughtful adjustments can restore normal function—and extend the life of your machine.

🔧 Unplug and Let It Defrost

Before doing anything else, turn off the unit and unplug it. Let it sit for several hours to allow all internal ice to melt naturally.

Some models have an auto-defrost mode, which kicks in when sensors detect ice buildup. But if your unit doesn’t defrost itself—or is completely frozen—manual defrost is the safest step. Place a towel underneath the unit or lift it onto a plastic tray to catch meltwater.

🔧 Raise the Room Temperature

If your room is below 65°F (18°C), try warming it up. You can:

• Use a space heater (placed at a safe distance)

• Open vents or doors to pull warmer air in

• Relocate the dehumidifier to a slightly warmer part of the room

Even raising the ambient temperature by 5–7 degrees can significantly reduce ice buildup.

🔧 Clean the Air Filter and Coils

A clogged filter or dirty coil is like a clogged artery in your HVAC system—it chokes performance and builds internal pressure.

Steps:

1. Remove the filter (usually accessible behind the front or back panel).

2. Rinse it under warm water, or vacuum if it’s just dusty.

3. Let it dry fully before reinstalling.

For the coils:

• Use a soft brush or a can of compressed air to remove visible dust and gunk.

• Avoid using water or cleaning spray unless the manual explicitly allows it.

• Never use sharp tools.

If the coils look oily or slimy, that’s likely mold or refrigerant issues—time to call in a technician.

🔧 Check and Adjust Fan Operation

If your fan isn’t spinning properly, airflow will drop, and ice will build. With the unit unplugged:

• Remove the front panel (or access point for the fan).

• Inspect for dust buildup or obstructions.

• Gently spin the blades with your hand. They should move smoothly.

If the fan is stuck or jerky, it may need lubrication—or a replacement motor if it’s buzzing, grinding, or refusing to start.

🔧 Make Sure It’s in the Right Place

As simple as this sounds, placement matters more than people think.

Make sure:

• The dehumidifier is at least 12 inches from walls or large furniture

• It’s standing on a flat, level surface

• Nothing is blocking the air intake or exhaust vents

Proper airflow prevents hotspots and cold pockets from forming inside the machine.

🔧 Set the Humidity Level Properly

If your humidity setting is too low (say, under 40%), the unit will overwork trying to hit an impossible target in a cool room. That overworking keeps the compressor running longer than needed—and freezes the coils.

Ideal indoor humidity: Between 45%–55%. Set your machine to 50% and monitor performance from there.

🔧 Try the Auto Mode or Low-Temp Setting

Modern dehumidifiers—especially from brands like Frigidaire, Midea, Hisense, and hOmeLabs—come with Smart Dry, Auto Defrost, or Low Temp Mode. Enabling these settings allows the machine to pause periodically and warm up internal components to prevent icing.

Example:
On a Frigidaire 50-pint unit, pressing the “Low Temp” button allows it to operate efficiently down to 41°F.
On Midea units, the Auto Comfort mode will switch compressor activity based on the room’s current temperature.

Always check your user manual for brand-specific settings.

How to Prevent Your Dehumidifier From Freezing Again

Once you’ve thawed it and made some adjustments, the real goal is to stop this from happening again. Here’s how to maintain year-round performance—especially during colder months.

🔁 Regularly Clean the Filter (Every 3–4 Weeks)

Treat your air filter like your HVAC system’s lungs. If it can’t breathe, the rest suffer. Cleaning it once a month ensures consistent airflow and reduces internal pressure build-up that leads to frost.

If you have pets, you may need to clean them every 2 weeks.

🌡️ Use a Thermostat or Thermometer in the Room

Install a small digital thermometer or thermostat in your basement, garage, or laundry room. If the temperature regularly dips below 60°F, consider:

• Warming the space

• Using a dehumidifier rated for low temperatures

• Shutting off the unit during the coldest hours

Some smart home setups even allow automatic dehumidifier shutoff if the room temperature is too low.

⚠️ Avoid Running 24/7 in Cold Spaces

Letting a dehumidifier run nonstop in cool air is asking for trouble. Most units aren’t built for cold operation, and continuous use will only accelerate ice formation.

Use timers, scheduling, or smart plugs to limit run time to the warmer parts of the day (mid-morning to afternoon). Let the unit rest at night if the space drops below 60°F.

🧊 Invest in a Cold-Weather Rated Dehumidifier

If you live in a colder climate or you’re dehumidifying a crawl space or unheated basement, not all machines will cut it. Look for models with:

• Auto-defrost

• Low-temperature operation (down to 41°F)

• Dedicated crawl space/basement design

Brands like Santa Fe, Aprilaire, or Frigidaire Low Temp models are built for this kind of environment.

🔁 Keep Coils and Vents Clean

Make it a habit to inspect and clean vents and coils once per season. Dust, mold, or pet hair build-up is a silent killer when it comes to airflow and efficiency.

Use a vacuum with a brush attachment or gentle compressed air every 2–3 months.

Brand-Specific Troubleshooting Tips

Every brand behaves a little differently when it comes to performance, sensors, and freezing. Here’s what to know:

Frigidaire Dehumidifier Icing Up

• Frigidaire models often come with auto-defrost but can still freeze if placed in very cold rooms.

• Try running on Low Temp mode, and make sure the coils and air filters are clean.

• If it ices up often, consider relocating to a slightly warmer area.

Midea Dehumidifier Freezing Up

• Midea units are known for efficient moisture removal but can overrun if set to Continuous Mode.

• Switch to Comfort Mode, which balances temperature and humidity to prevent overworking the compressor.

• Ensure room temp is above 65°F for best results.

Hisense Dehumidifier Frozen Coils

• Hisense dehumidifiers can suffer from sensor calibration issues over time.

• A hard reset (unplugging for 10 minutes) can sometimes fix faulty humidity readings.

• Check for firmware updates if your unit has Wi-Fi/smart control.

Portable Dehumidifier Freezing

• Smaller portable units are particularly prone to icing in cool rooms since they lack strong airflow systems or defrost modes.

• Never use a portable unit in unheated basements or garages unless it’s designed for that use.

• Always place them at least a foot away from the walls.

Final Thoughts: Stop the Freeze, Save the Machine

If your dehumidifier is icing up, don’t panic or rush to replace it. Nine out of ten times, it’s an issue with temperature, airflow, or settings—not a sign that your unit is broken. Whether you’re using a Frigidaire, Midea, Hisense, or a smaller portable model, the steps are often the same: defrost, clean, adjust, and observe.

🔁 Let’s recap what to do when your dehumidifier ices up:

• Unplug and let the unit defrost naturally

• Warm up the room or move the unit to a less chilly area

• Clean filters, coils, and vents regularly

• Make sure the fan is spinning freely

• Set your humidity target to a realistic 45–55%

• Use auto defrost or low-temp modes if available

• Consider upgrading to a low-temperature-rated dehumidifier if you’re in a colder climate

And always remember—maintenance is your best prevention. Just like you wouldn’t let your car run without oil, your dehumidifier needs the occasional checkup to run right.

👉 What You Can Do Right Now

If you’re staring at a frozen unit right now:

1. Unplug it and let it thaw.

2. Clean the filter and check the coils.

3. Review your room’s temperature—use a thermometer if unsure.

4. Try adjusting settings to a higher humidity level.

Then, if it’s still icing up after trying all that:

• Relocate the unit to a warmer space

• Call the manufacturer’s support (especially for newer models)

• Or consider buying a cold-climate-ready unit if needed

🧰 Want to Keep It Running Smoothly Long-Term?

We suggest setting a reminder every 3 weeks to:

• Clean your air filter

• Check the airflow around the unit

• Inspect for dust or frost buildup

Simple routines like this make all the difference—especially during colder months when dehumidifiers are most at risk of freezing.

If you’re considering replacing your unit or need a better one for basements or colder areas, let us know. We’ve tested dozens of models and can help match you with a reliable unit that works in your conditions—without wasting money or time.

Now that you know how to fix and prevent a dehumidifier from freezing up, what’s stopping you from checking yours right now? A few small adjustments might be all it takes to get it humming along like new again.

Want help choosing a dehumidifier for cold rooms or basements? Just check—we’ve got real-world advice that skips the hype.