Dehumidifiers are the kind of appliances that you set and forget as they work quietly in the background. So, a unit that becomes loud and noisy definitely has a problem that you must troubleshoot as soon as possible.
Dehumidifiers will become loud and noisy if their fan blades or blower wheels are damaged, misaligned, or incorrectly installed. Besides that, a worn-out fan motor will also make loud noises as it works to power the fan. On refrigerant-based dehumidifiers, faulty compressors will cause loud knocking and grinding noises.
In most cases, you can fix your dehumidifier yourself. This guide will show you how by explaining why it’s loud and noisy and explaining how you can fix it.
Why Is My Dehumidifier Loud And Noisy?
There are very few moving parts in a dehumidifier. So, any unusual noises likely come from the fan, blower wheel, or compressor.
This section will help you troubleshoot those parts thoroughly to find and fix the problem.
Blower Wheel Problems
About this: All compressors need a way to draw air into the appliance so the unit can remove the air’s moisture. Depending on your dehumidifier brand and model, it likely has a blower wheel that serves that purpose.
The blower wheel is essentially a fan that’s cylindrical in shape. It has fins or blades that cause air to move when the wheel spins.
A dehumidifier will spin its blower wheel whenever it senses that the humidity levels are too high and needs to remove moisture from the surrounding air.
What’s wrong: The first reason your dehumidifier is loud and noisy is a problem with the blower wheel.
The blower wheel makes a lot of noise when it’s loose, misaligned, or installed incorrectly. When that happens, the wheel grinds against the dehumidifier’s insides loudly and noisily.
How to fix it: You can solve this problem by detaching the blower wheel and reinstalling it correctly. When you attach it, be sure to avoid over-tightening it in place.
Then, spin the blower wheel manually to check for any alignment issues that need adjusting.
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Please note that if the blower wheel is damaged from rubbing against the dehumidifier for too long, you’ll need to replace it with a new one. The damaged blower wheel will cause further problems later on.
Fan Blade Issues
About this: Aside from a blower wheel, some dehumidifiers use fan blades instead. Unlike a blower wheel, these fans consist of tilted blades that are rotated to move air.
Despite the difference in shape, fan blades serve the same purpose as blower wheels: to draw air through the dehumidifier so it can remove moisture from the air.
As long as the fan blade in your dehumidifier is installed correctly and well-aligned, there should be no noise.
What’s wrong: The fan blades in your dehumidifier can also become loud and noisy if installed incorrectly.
After all, this part spins at high speeds in a small section of your dehumidifier. So, any slight misalignment can cause the fan blades to continuously hit the inside of the appliance, leading to loud noises.
How to fix it: Depending on how much damage the fan blade has suffered, you can get rid of the noise by realigning and tightening it appropriately.
However, if the fan blade is extensively damaged, replacing it with a new one is the best thing to do. Just be sure to reinstall the new one correctly so this problem doesn’t repeat itself.
Worn-Out Fan Motor
About this: Whether your dehumidifier uses a blower wheel or fan blades, it’ll undoubtedly have a fan motor. The motor is the component that generates power to spin the wheel or blades so it can draw air through the dehumidifier efficiently.
The fan motor is electrically powered, which means it is connected to the rest of the appliance with wires.
As mentioned earlier, the fan motor is powered whenever humidity levels are too high and the appliance wants to draw in to remove moisture.
What’s wrong: Fan motors can get loud and noisy when they start to wear out. Typically, that happens because of old age, after the motor has been used for many years.
However, given how dehumidifiers work to remove moisture, the motor could also get damaged from exposure to water.
Lastly, an electrical fault like a power surge might also damage the motor, causing it to make loud noises when it operates.
How to fix it: A worn-out or damaged fan motor can’t be fixed or repaired. However, once it starts making loud noises, it’s clear that the unit is damaged and needs to be replaced with a new one.
It’s best not to delay this replacement because you can’t use the appliance comfortably until the motor is replaced with a quiet one.
About this: There are two types of compressors: the ones that use desiccants to remove moisture from the air and the ones that rely on circulating refrigerant instead.
The refrigerant-based dehumidifier has a compressor inside the unit. Its job is to circulate the refrigerant through coils so they become cold and can dehumidify the air that passes through.
What’s wrong: When a compressor works correctly, it’ll only produce a gentle humming sound. However, a faulty or damaged one will give off a loud grinding or knocking noise.
That’s because the components inside are damaged by excessive wear or electrical faults. When that happens, the internal components will hit the inside side of the metal compressor or grind against other metal parts.
Compressors don’t fail so often or so quickly. But when they do, they can get very loud and noisy and will likely require a replacement.
How to fix it: Firstly, remember that the compressor is part of the dehumidifier’s sealed system. The system is sealed to ensure that refrigerant can circulate without leaking into the surrounding environment, which isn’t good.
As such, only technicians certified by the U.S. Environmental Protection Agency (EPA) can troubleshoot, repair, or replace it.
A technician might be able to troubleshoot the compressor, though it’s more likely that you’ll have to replace it with a new one.
Unfortunately, compressors can be pretty pricey. So, you’ll have to do the calculations to determine if you should pay for a new compressor or invest in a new dehumidifier instead.
Frequently Asked Questions (FAQs)
Troubleshooting a loud and noisy dehumidifier can be challenging at times. So, here are a few more questions and answers to help you understand what’s happening:
Is It Worth Replacing A Dehumidifier Compressor?
That depends. Some dehumidifier compressors might still be under warranty, so you can get them replaced for free. However, it’ll likely take some time to get a replacement. However, if your dehumidifier is old or the compressor costs too much, you’re better off buying a new dehumidifier.
Should I Run A Dehumidifier Fan On Low Or High?
You should run the dehumidifier fan on high if you need the appliance to quickly remove moisture from the air. However, putting it on low is enough if you’re using it to maintain humidity levels.
What Refrigerant Is Used In Dehumidifiers?
Dehumidifiers typically use R-410A refrigerants. However, some older models might still use R-407C. Modern dehumidifiers do not use Freon.
Are Dehumidifiers Easy To Fix?
Dehumidifiers are generally easy to fix because they have few moving parts and their components aren’t too complex. However, it can be challenging to fix if there’s a problem with the sealed cooling system, as that requires a certified technician.
Are Desiccant Dehumidifiers Quiet?
Yes, desiccant dehumidifiers are very quiet. While they might use fans, they do not have a compressor or a sealed cooling system that makes a lot of noise.