Dehumidifiers keep the air in your home dry during the summer months. Unfortunately, with all electronics they have their flaws.
If your dehumidifier keeps shutting off, there are several reasons why this might be happening.
A dehumidifier removes moisture from the air. They come in two main types: whole house and portable. Whole house models are usually installed in the attic or basement of your home.
Portable units are typically placed near windows or doors.
There are several things that can go wrong with a dehumidifier. The most common reason your dehumidifier shuts off is because it is full.
This means that the unit cannot remove enough water from the air to meet the humidity level inside your home.
Dehumidifiers can prevent mold, and mildew buildup, so if your dehumidifier stops working properly, it can be problematic.
In this article, I am going to show you the 11 common reasons your dehumidifier keeps shutting off and what to do about it.
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1. The Filter is Blocked
One of the most common reasons for issues with a dehumidifier is a dirty and clogged filter. When this happens, the air that flows through the filter is blocked.
Because of this, the compressor has to work so much harder to keep the airflow sustained. As a result, there is more energy used, as well as the generation of heat.
In a dehumidifier, there are normally two filters. Air that passes through a dehumidifier is cleaned by these filters. One filter is positioned at the intake, and the other is placed at the exhaust (or delivery).
If air becomes blocked in these two filters (because it is dirty), the compressor will heat up.
Clogged filters will also cause frosting on the evaporator coils (linking opportunity). This causes a low rate of air flow.
This happens because airflow is poor, and not enough air reaches the cooling coils. The temperature of the coils decrease, and ice builds up.
In turn, the dehumidification becomes reduced causing the compressor of the dehumidifier to shut off. It then goes into a mode to defrost that helps the ice melt.
What to Do
If you think the filter could be the issue because you have not taken care of them for a while, then your first port of call will be to take a look at them.
It is recommended that you clean the filters every week, especially if you are using the dehumidifier on a daily basis. There are also those who think you should just clean them every three weeks, or even after a few hours.
If you are unsure, take a look at the instruction manual to refer back to anything you need to know about the upkeep of your dehumidifier.
Keeping your filters clean every week will help to keep the dehumidifier in tip-top condition, and it will give you a good indication of when something might be up that is not connected to blocked filters.
If they need a clean, using lukewarm water to give them a gentle wash should do the trick. Make sure it is fully dry before you put it back into the machine. You also should not need to replace the filter as they are reusable.
A Leak is Causing Lack of Refrigerant
If you find that your dehumidifier keeps switching from ON and OFF, then it is possible that the refrigerant is low.
However, this should not happen to a refrigerant dehumidifier. In fact, they are supposed to have the same amount of refrigerant in them for their whole working life. So why is it changing from ON and OFF?
This is because the leakage of a refrigerant causes lower pressure of the refrigerant lines. When the pressure is reduced, it can do so to the extent that the compressor will turn off before the cooling cycle has been completed.
After a while, once the pressure increases, the compressor will turn back ON. If this keeps happening, it can actually cause damage to the internal workings of the dehumidifier.
What to Do
If you find that your dehumidifier is turning OFF and ON in short working cycles, look for refrigerant leaks. Check to see if your dehumidifier was hit at some point, or if there is an odd shape or dent.
Since it’s hard to tell if there is a leak, it’s worth calling in an expert who can diagnose the leak for you. They will be able to find out where the leak is, patch it up and get it working properly again.
Temperature is Not Correct for Dehumidification
Many dehumidifiers work like an air conditioning unit. They have a vapor compression cycle, meaning they use a refrigerant to dehumidify the space they’re in.
This is done by a fan which causes airflow in the dehumidifier. The air reaches the cool evaporation coils which have a lower temperature than the air itself. This cooler temperature is called the ‘dew point’.
This means the air is cooled to the temperature at which water vapor in the air condenses and turns into a liquid. This completes the dehumidification process.
If the temperature of the air is too low it generates ice on the coils, which is called frosting. This buildup of ice will restrict airflow, leading to poor dehumidification.
For your dehumidifier to work properly, the room temperature should be around 70 Fahrenheit to 90 Fahrenheit. If you have a refrigerant dehumidifier, then do not use it below 60 Fahrenheit.
If this is something you are generally worried about, then more modern dehumidifiers have built-in anti-icing features which will help to stop this from happening.
What to Do
There are a couple of solutions if you live in an area where this happens often to your dehumidifier. One way to sort this situation out is by increasing the temperature of your room. Not only will it make the room a more comfortable temperature to stay in, but it will stop frost from forming on your dehumidifier.
Another way to avoid this from happening is by having a different dehumidifier. One of the options is a desiccant dehumidifier which works no matter the temperature of the room. This is a good one to use in a basement, for example. (Link to dessicant dehumidifier)
Blower and Fan Speed is Not Working Efficiently
The terms ‘blower’ and ‘fan’ both mean the same thing: to push air through the dehumidifier. They generate airflow that has been created solely to be used within the dehumidifier.
When that forced air comes in contact with the cool evaporator coils, the coils take on some of the heat. The temperature of the air then goes below the dew point, and the humidity itself is extracted.
In order for it all to work properly, the fan speed must be high enough for good airflow. If the fan’s motor or blades are damaged then the airflow drops.
If the airflow drops, there will not be enough air to keep the coils from getting too cold. If this happens ice forms on the coils.
If your dehumidifier has a built-in anti-ice mode, then the ice will melt. The dehumidifier’s fan speed drops until all of the ice melts.
If there is constantly less airflow, ice will just keep building up and melting on a repeated cycle. The shorter cycles will cause the dehumidifier to consume more energy whilst not getting rid of the moisture in the air efficiently.
What to Do
There are a few reasons why the fan speed dropped.
The first one could be that someone or something damaged the motor or it was damaged upon arrival. If this happens you need to replace the dehumidifier or have a technician repair it.
The other possibility is something damaged the blades. If the blades are damaged, the fan cannot pull enough air through the dehumidifier. If the blades are damaged then you need to replace the dehumidifier.
A quick note, depending on the size and cost of your dehumidifier, most of the time it is better to just replace the dehumidifier. If you have a larger more expensive model, then we recommend having a technician repair it.
Dehumidifier Humidistat is Malfunctioning
Also known as humidity control, the humidistat is a really important component to a dehumidifier because it is what controls the machine to know when it should stop. This is the area that detects the current humidity in the air.
Once the humidity has reached a certain number, it signals for the compressor to switch off. Once the humidity in the room rises, the cooling cycle restarts and switches the compressor on.
If the humidistat is faulty, it will measure the wrong humidity level. This means the compressor will shut off it reaches the desired humidity in the room. Which leaves the space with too much moisture in the air.
One way to tell if this is happening is if you have to adjust to reach lower humidity than necessary so the dehumidifier won’t shut off.
What to Do
If this happens a lot, go buy a hygrometer to get an accurate reading. On the control panel of your dehumidifier, select the humidity. The humidistat will turn off the dehumidifier when this level of humidity is reached.
Compare the value alongside the humidity monitor to make sure there is a difference. If there is, it’s time to replace your dehumidifier or get the humidistat repaired.
Dehumidifier Coils Are Clogged Up
Like we mentioned earlier, once air moves through the dehumidifier, it comes into contact with the cooling (evaporation) coils.
The temperature of the trapped air drops below the dew point, and the moisture in the air converts into a liquid. This liquid collects in the dehumidifiers basin.
The condenser coils brings the temperature of the cooler air back to room temperature.
To successfully dehumidify a room, your device needs proper airflow.
When your cooling coils and condenser coils are clogged you get poor airflow. Poor airflow freezes your coils.
When coils are clogged with dirt and debris they make the air quality worse.
Clogged coils makes the device work harder which shortens it’s lifespan and increases your electricity bill.
What to Do
The fix is simple: keep the coils clean. Buy a soft brush and clean the coils every now and then. Make sure to brush in the direction of the tubes as they are extremely delicate and sensitive.
If you brush too hard and damage the coils, you risk needing them replaced to prevent a possible leak.
Some dehumidifiers allow access to the coils, so it depends which model you have.
If there is no way to reach them, or you don’t want to risk damaging them, vacuum through the holes instead to reach the coils.
Obstructions Causing Lack of Airflow
Just like we said earlier, if a dehumidifier doesn’t have good airflow it will cause problems with the device. Problems like the coils freezing or if the compressor overheats.
When either of these happen, the dehumidifier will shut off before completing its job. This is why its crucial to remove any blockages that could obstruct the airflow.
What to Do
You can solve this easily. First, keep the dehumidifier away from objects around it that prevent air to reach the machine. This means moving furniture away from the dehumidifier so as to not be directly behind or in front of it.
Keep plants and decorations away from the dehumidifier. Put objects that block airflow far from the device.
Compressor Unit is Faulty
In my experience compressor, is the most important part of your dehumidifier. It is required for the dehumidifier to work properly during the cooling cycle.
It is the component that helps to pressurize the refrigerant.
Althought it isn’t common, it’s possible your compressor is overheating.
If you find that the dehumidifier shuts off after unfinished cycles, the compressor might be overheating.
This happens when there is a buildup in the compressor that restricts the refrigerant flow. Your compressor will get too hot and ultimately shut off. Once the compressor has cooled down, it will restart again. It will repeat this process over and over.
You end up with a dehumidifier that doesn’t do its job because it keeps shutting off and restarting.
What to Do
Unfortunately, most of the time when the compressor breaks, it’s better to just get a new dehumidifier.
You could just replace the compressor itself, however, it is very costly. Compare the price of a replacement and a new dehumidifier. If it costs the same or more to replace it then I recommend you just buy a new dehumidifier.
The Settings Need to be Changed on Control Panel
We’ve all been there. Sometimes, we think there is an issue with any device when we come to find out it was just on the wrong mode.
If your dehumidifier has not finished a cycle its possible you selected the wrong humidity level.
It is hard to know the correct humidity to choose compared to the temperature of the room.
A good rule for you to follow is to just pick a percentage of around 30 to 50 percent. That way you will always be below 60 percent.
If your dehumidifier is turned off, there’s a chance you chose a percentage too close or above the humidity in the room. This can cause the dehumidifier to shut off after doing next to nothing.
Fortunately, your dehumidifier still works, but you just need to pick the right humidity.
The dehumidifier could also turn off because it has a timer. If it is set on a timer it will shut off despite completing its job.
What to Do
First, find out the humidity of the room with a hygrometer.
Second, check the control panel of your dehumidifier. See what you have selected.
If you chose the wrong humidity percentage or if its set on a timer, change these settings. Make sure you haven’t chosen any restrictions either.
Over time you may not even need to use the hygrometer as you might get a feel for the room’s humidity, or just learn what to use.
If you feel overwhelmed by all the controls, and feel daunted by changing the settings, try not to be. If you feel like you have applied the wrong setting, just switch the controls back to the default settings and go from there.
Electronic Components Have Begun Malfunctioning
Here are some of the electrical components to familiarize yourself with when it comes to a dehumidifier:
Capacitor
There are two of these which store and release electrical energy. One starts the compressor, the other rotates the fan.
Switch
This is what controls the fan as well as the power.
Relay
This makes sure that there is safe switching when it comes to the components of the dehumidifier. It is a low powered switch which controls the higher powered switch.
Fuse
All electrical items need a fuse. It helps to prevent any components of the dehumidifier from burning because of surges in electricity.
Control Board
Every single electrical component is connected to the control board. It has different lines which feature a plethora of voltages.
You Have A Bad Capacitor
The majority of dehumidifiers rely on vapor compression cycle. This is just a fancy term for the whole process: trapping the air, cooling it, pulling the moisture from the air, turning the moisture into a liquid, collecting it, and pushing the air back out into the room.
Since we’ve walked you through some of the problems, you realize there are many steps involved. All of these steps rely on certain electronic parts for it all to run smoothly.
If you find that your dehumidifier shuts off and restarts, runs in short cycles, or if it struggles to start a cycle, then you have an electrical component has either become damaged or is defective.
It could be the electrical parts, or the wiring. If your dehumidifier runs for only short periods, your device might have a bad capacitor. This part powers the compressor. If the capacitor is no longer working, your machine stops completing full cycles.
To know if this is damaged, you will find it bulging on top – however, this could also mean the capacitor works just fine!
What to Do
If you feel confident about your expertise in electrical wiring, go ahead and check to find the wiring that stopped working.
Look at the internal and external wiring to make sure everything checks out. You do not need to be an expert to see if there is burnt or damaged wires. Check for loose connections.
Check to make sure everything is connected to the control board. Look over the individual parts of the dehumidifier, like the compressor.
Study the circuit, and seeing if there are any discontinuations.
If there is damage on the electrical front, weigh your options. Compare the price of the dehumidifier vs getting it repaired, or just buy a new one.
If you are not experienced with electrical work and want it repaired, seek professional advice.
Bucket/Basin Placement and Float Switch
As we’ve discussed, dehumidifiers collect water from the air in a room and stores it in a drain basin or bucket. Once this container is full, you need to empty it.
To keep itself from overflowing, it shuts off using a sensor called a float switch. This signals to the control board of the dehumidifier to stop running.
When the float switch keeps tripping, it will send a signal to the dehumidifier compressor and fan turning them off. , even if the basin is not full.
If you notice that the dehumidifier will not turn on or if it turns off after you have had it running for a short time, then have a look to see if the light for the basin being full is lit. If you notice that it is constantly on, or is flashing, then there is a good chance that it has become defective.
This means that it is stopping the dehumidifier from completing a full cycle, and it will not remove all the moisture from the air.
Another reason is the basin was not correctly placed within the dehumidifier.
Once you have emptied it or cleaned it, usually there is a push switch which is pressed making the dehumidifier begin to work.
This push switch makes sure that the basin is placed in the dehumidifier properly. Without it, it has the chance to not be put back properly meaning the dehumidifier may keep running and cause all that water to build up and go all over the floor.
This is also terrible when it comes to safety. If the basin is not fitted properly, a loose connection could potentially stop the dehumidifier from turning on, and can also stop it from working a full cycle.
It’s possible that the push switch or the basin is damaged.
What to Do
If you notice that the basin full light is on, then this is the reason why there is a problem with the working of the dehumidifier. There are a couple of steps to take to help solve the issue.
First, remove the basin. If its full, empty it and put it back. The dehumidifier shoud start working again.
Secondly, if the above is not the reason and the basin is empty even though the dehumidifier is saying it is full, there could be a problem with the float valve. It could need replacing, repaired, or perhaps just a little adjusting.
If you have an issue with the placement of the basin, then the above will not provide a solution. Instead, look for an obstruction which is causing the basin not to fit in the dehumidifier properly.
If it does fit properly, then remove the basin and apply pressure on the push switch with your hand. If this causes the dehumidifier to switch on, then it means you need to have the push switch replaced.
Frequently Asked Questions
Is a Dehumidifier Meant to Shut Off Automatically?
If your dehumidifier shuts off automatically, don’t assume that there is a problem, this is how it was designed.
The dehumidifier has a default setting when you buy it. Its already set to a specific humidity level. Once it has removed set moisture, it will shut off.
Fortunately, you can change this setting. Even so, all dehumidifiers have a sensor, and once that says it has reached the limit of moisture it is supposed to remove from the air, it will automatically shut off.
The reason for this function is so the dehumidifier does not overwork, take too much moisture from the air to dry it out completely, waste power, and fill up very quickly.
Some may even shut off once it senses that the water basin is too full to avoid any spillage.
Still not convinced? Go through the checklist we talked about.
What About If I Want a Dehumidifier to Work Continuously?
It actually not a good sign if your dehumidifier runs constantly. If your dehumidifier never shuts off then the sensor is broken because it cannot tell if it reached the set humidity level.
It is healthy and normal to have some moisture in the air. If there is too little moisture, then a dehumidifier may actually struggle to work, and therefore shut off. For optimum performance, the moisture content in the air should be around 50 percent or more.
What Does it Mean if My Dehumidifier is Not Removing Enough Moisture From the Air?
If your dehumidifier isn’t pulling enough moisture from the air then its not working as it should or you need to add another dehumidifier to the room. That’s why it’s important to pick the right size for the room beforehand.
The bigger the room, the more likely one dehumidifier will not be able to do the job. With this in mind, add in another dehumidifier and see if it starts to work better.
Can You Reset a Dehumidifier?
Unlike an old Nintendo 64 or an iPhone, you cannot reset some dehumidifiers – not in the conventional way of using a button, anyway. If it keeps shutting off, then you could try a ‘full reset’ which is a little like what you would do with a computer.
To reset, unplug the dehumidifier for two minutes and plug it back in.
However, newer models have a ‘reset’ switch, rather than just an ‘off’ and ‘on’ button. If yours is a little old school, then it might be worth upgrading so you can make the most of the updated functions.
Final Words
We understand its frustrating when your dehumidifier stops working correctly.
Most of the time the answer is simple. You might have pet hair getting stuck and causing a blockage, or the factory setting which is not suitable for the room. Sometimes your dehumidifier has a part that has kicked the bucket.
When this happens don’t panic, make sure you go through this checklist before spending money on repairs or a new one.
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