Dehumidifiers are meant to take moisture out of a room, not put it back in, so if you notice your dehumidifier leaking, something isn’t right.
A leaking dehumidifier can damage your belongings, and if left untreated, it will cause irreparable damage to the appliance, so it’s important to fix the issue quickly.
In this guide, I’ll run through the most common reasons why your dehumidifier is leaking and give you simple solutions for each problem.
Your dehumidifier collection bucket or water tank stores all the condensed water within the device.
Often, when the dehumidifier is leaking, it’s because the water tank is misaligned or not quite sitting properly within the appliance.
This means water can spill into other parts of the dehumidifier and leak out into your home.
This usually happens if you’ve recently assembled, cleaned, or emptied the dehumidifier and something isn’t in the right place.
- Turn off the dehumidifier.
- Open the device and check if the water tank is in the right place and aligned. Use your user manual if necessary.
- Once adjusted, seal the device and run the dehumidifier again. Check it frequently to make sure it’s staying in position.
Dehumidifiers have a water tank or reservoir bucket which collects the moisture.
If this becomes damaged, it can cause water to spill into the device and out into your home.
The water tank or reservoir compartment can become cracked or damaged if knocked into other objects or dropped.
These cracks are particularly common with portable and personal dehumidifiers, which are moved regularly.
- Turn off the dehumidifier and remove the water collection bucket/drip tray.
- Check the water tank for any visible damage or cracks. Fill the collection bucket with water and see if there’s any water dripping through.
- For any small leaks, use waterproof adhesive plumber’s tape. This should stop the leaks, but it’s only a temporary fix. 
- Put the water tank back in the dehumidifier and run a test cycle.
- Replace the collection bucket/drip tray as soon as possible.
Dehumidifiers running frequently are usually connected to a drainage hose pipe so they can run continuously without having to be emptied manually.
These hoses are particularly useful in very a very damp environment where your dehumidifier is running continuously.
A disconnected drain hose will cause the condensed water collected from the air to leak out into your home.
New units often don’t have the drain hose connected yet. It may also be that you have moved your dehumidifier and forgotten to reconnect the drain hose.
- Check to see if your drain hose is attached. It should be connected to the back of your dehumidifier (usually at the bottom near the water tank) and have a drain connection.
- Turn off the device and connect the drain hose at both ends.
- Turn the dehumidifier back on to see if it functions properly. The connection will need to be secure on both ends to prevent leaks.
For proper drainage, you should have a hose-fitting cap connecting it at both ends.
If your drain pipe is fully connected but it’s still leaking, then it could be a problem with the connection.
Drain hose caps can wear out over time. It may also be damaged or become loose if you’re connecting and reconnecting it frequently.
- Disconnect the dehumidifier.
- Remove the drainage hose from both ends.
- Check the fittings and clean them.
- Look for a rubber O-ring on the female end of the hose connection. If this is missing or damaged, then replace it.
- Reattach and hose and tighten it at both ends.
- Run the dehumidifier and check for any new sources of moisture. You can use plumbers’ tape to secure it even more tightly if it’s still leaking.
Your drain hose needs to be long enough to reach the floor drain or external drain, but if it’s too long, the water may not have enough momentum to travel through it.
This can lead to water pooling in the hose or traveling back into the appliance, causing leaks.
This is usually because the dehumidifier is installed in a basement or a sub-zero level and has to travel a long way to the drainage point.
It’s more common with a portable dehumidifier that connects to multiple drainage points.
If your drain tube or hose isn’t the right size, then you have 3 options:
- Move the dehumidifier closer to the drainage point. This is the simplest solution but may make your dehumidifier less effective if it’s further from areas of high humidity.
- Install a separate water pump and connect the drain hose to it. This will pump the water out and stop it from pooling.
- Look for modern dehumidifiers with a built-in water pump that can force water out. Buying a new dehumidifier can be expensive, though.
Your dehumidifier will usually rely on gravity draining.
Unfortunately, if your drain hose coils vertically, it could mean that gravity works against you, leading to water traveling back down the drain.
This is usually because your dehumidifier is on sub-ground levels and hasn’t been installed correctly.
It can also be an issue if you’ve moved the dehumidifier or drain hose and it now has a vertical lift.
If your dehumidifier is leaking because your drain pipe isn’t correctly installed, then you have 2 options:
- Raise the dehumidifier, so it’s draining downwards. The easiest way is to place it on cinder blocks or a shelf, but you can have it installed properly on a higher floor.
- Install a drainage pump to force water up against gravity and into your drains. Modern models include these inside your dehumidifier as standard, but older units won’t.
Kinks and bends in a drain pipe or garden hose are common.
These make it harder for the water to flow and can lead to pooling water building up in your pipe and leaks.
Your drain pipe usually becomes curled, kinked, or bent if it’s installed incorrectly or as you move the device. It can also be because your hose is too long.
- Turn off your dehumidifier.
- Follow the route of your drain pipe and look for any bends, kinks, or sharp turns.
- Disconnect the water pipe from the bottom of the appliance and straighten it out, so it’s leading to the floor drain or outside drainage using the shortest route possible.
- Use other objects to hold the pipe securely in place if needed.
- Reconnect the drain pipe and run it to check the dehumidifier correctly drains without leaking.
If the drain pipe you’re using is too small, then it won’t be able to handle the amount of water coming from the dehumidifier.
Larger units will usually remove water more quickly, but smaller diameter hoses might be unable to keep up with the amount of moisture being created.
This can lead to water leaking from the connection.
This is usually just because you’ve got the wrong size drain line installed. Every different dehumidifier works at a varying rate, and you must ensure it matches.
- Attach a larger hose. Large dehumidifiers use a ¾ inch connection as standard, but you usually have the option to connect a larger hose instead. A small or portable dehumidifier with smaller hose hookups (usually ½ inch) may not have this option.
- If your dehumidifier doesn’t have a wider hookup, you’ll need to replace your dehumidifier completely.
If your hose is positioned properly without a too long horizontal gain, no vertical coiling, and no loose connections, it could mean an internal blockage.
This is a common cause of dehumidifier leakage and prevents your device from working properly.
A blocked hose is almost always caused by loose debris entering the pipe.
This is more likely to come from the drainage end, especially if the drain leads outside, where insects and other debris can get in.
A blocked pipe could also be caused by dirt building up in the dehumidifier, pump, or drainage system.
- Unplug the dehumidifier and remove the drainage hose from the device.
- Keep the pipe connected to the drain, and use a second hose to pass clean water through it. Try to blast the water through with some pressure to remove any big blockages.
- If the hose is still blocked, you must clean it out. Soak it in soapy water for a few hours, or find a specialist cleaning solution that can dissolve dirt and grime.
- Once the cleaning is done, reconnect your hose to the dehumidifier and turn it on.
- Hopefully, it’s working properly, but if not, you’ll need to replace the drain hose.
Many dehumidifiers use a water pump to force water up and out of your home.
Without a working pump, it can lead to overflowing water in the tank which can leak into your home.
Pumps can easily become jammed with debris. This may have been in the pump to start with or could have come through the pipes while it was running.
- Unplug your dehumidifier and remove the pump (use the owner’s manual for guidance if needed).
- Check for any dirt or debris in the device and clean it with hot soapy water.
- Check the connections. Some pumps will automatically switch off if there’s a loose connection.
- Reconnect the pump and turn the dehumidifier back on. If it does start leaking, then you may need to completely replace the pump.
Most dehumidifiers use refrigerant in cold coils to condense the moisture from humid air.
These dehumidifier coils can freeze over, and when they do, it can cause the dehumidifier to stop working and leak.
If left untreated, the frozen coils can permanently damage the dehumidifier.
Usually, this is because the dehumidifier is being used in low temperatures.
If the temperature goes below 65 degrees Fahrenheit, then the coils are likely to freeze over.
Some modern devices have a built-in thermometer to monitor the temperature and stop the device from running when it’s too cold.
The other reason your coils freeze over is because there’s a malfunction.
This is often because your blower wheel isn’t working, and there’s not enough airflow to stop the coils from freezing.
It could also be an issue with the thermostat or humidistat causing trouble with the settings.
- Check the temperature. If your device is operating in conditions under 65 degrees, then you should move it to another part of your home or place a heater nearby. This should get it working again, but it may up your energy bills.
- Check the fan. You should be able to hear the fan running when you use the dehumidifier, and if it isn’t, then you should turn off the device and open it up to perform maintenance and testing. You may need to buy dehumidifier spare parts to replace it, but if you don’t have experience, you should consult a professional.
- Check the internal electrics. Unfortunately, you may need to replace parts of the electrical equipment within the dehumidifier, which takes some expertise. It’s best to consult a professional for advice.
Most new models have an automatic shut-off feature, so the device won’t remove moisture from the air when the water collection bucket is full.
In some cases, this switch is used to trigger built-in pumps to drain water.
Many dehumidifiers use a float switch that floats up on top of the water tank. When it reaches a certain point, it triggers the device to shut down.
Broken overflow switches can cause a dehumidifier leak because water is coming into the appliance with nothing triggering it to drain out.
The most common reason your overflow switch fails is that it isn’t installed correctly or in the correct position.
Broken switches are also common in older devices because they can burn out over time.
- Turn off the device, open the dehumidifier, and inspect the broken switch.
- Check the user manual to see if it’s positioned correctly. If not, move it to the proper location within the water bucket.
- If there’s any visible damage, or it still isn’t working, you’ll need to replace it.
- If the switch can’t be replaced, you’ll need to replace the dehumidifier.
Gravity draining dehumidifiers rely on negative pressure for water to flow out.
If your drain is blocked with pooling water, then the water won’t drain, and it will either stay in the pipe or go back into the dehumidifier, causing leakage.
A blocked drain is usually caused by a physical blockage in the system.
This is typically caused by a build-up of dirt, grease, and grime, but it could be a bigger plumbing issue.
- Raise your drain hose so it’s sitting above the standing water. This will balance the pressure and let water flow through.
- Check the drain system for blockages. You may need to consult a professional to establish what the issue is and how to fix it.
- If possible, you can try to connect your dehumidifier to a different drain that isn’t blocked, but this won’t be possible in every home.
Your dehumidifier or HVAC system will usually have a filter that air passes through.
This helps to improve the air quality by removing some pollutants in your home, but over time it gathers dirt and can become blocked.
If it becomes blocked, it can damage the dehumidifier leading to overheating and leaks. It can also cause dirt and bacteria to spread in your home 
Dehumidifier air filters naturally become dirty over time as they remove pollutants from the air.
If it’s blocked, it’s probably because you haven’t done proper maintenance and cleaning on the air filter.
- Turn off the device and remove the air filter. This is usually very straightforward.
- Use a vacuum on the filter to remove visible dirt and dust.
- Soak the filter in soapy water and gently clean it. Leave it to dry completely.
- Replace the dehumidifier in the unit and then turn it back on.
- In some cases, you will need to replace your dehumidifier filter. Check the manufacturer’s instructions and order replacement parts as needed.
Most leaks can be solved by tweaking and getting components in the correct position, tightening connections, or performing routine repair work.
If your machine is under warranty, you might even be covered for labor and replacement parts.
However, there are some cases where the issue can’t be fixed:
If your dehumidifier is leaking and the repairs aren’t working, you need to consider a replacement unit.
For larger or whole home models, you can consult a professional to look at it, but for cheaper dehumidifiers, you’ll just need to replace it.
Your dehumidifier is designed to collect water vapor from the air, so if it’s not collecting water, then it isn’t fulfilling its purpose.
You can look at the motor or fan and potentially do some repair work, but most of the time, it’s an issue with the internal sensors or mechanism.
In some cases, there could be a refrigerant leak, so the cooling pipes aren’t drawing moisture from the air.
Refrigerant gas can be hazardous, so you may need to contact a professional to help you dispose of it safely. 
If your device is freezing over constantly, it’s usually an issue with the humidistat and temperature sensors.
These can be repaired, but in most cases, it’s cheaper and simpler to replace the appliance.
If your dehumidifier won’t turn on at all, it’s usually a problem with the internal sensors or the electronics.
There are some repairs you can do, but generally, the device needs to be replaced.
You should stop using your dehumidifier if it is leaking. Once you have diagnosed and resolved the problem then you can use the dehumidifier again. If you are unable to fix the issue then you will need to replace the appliance.
If your dehumidifier has a water leak then you should not use it until the problem is resolved. Once the leak is fixed you should leave the device to dry for a few hours before using it again.
A well-maintained residential dehumidifier will last 5-10 years.
Leaking from the bottom of your dehumidifier is quite common, and most of the time, it’s just a small issue with the drain tube or water collection bucket.
You’ll need to troubleshoot a few different areas to find the exact issue, but once you do, you’ll likely be able to get it draining properly without replacing it.
Hopefully, this guide has shown you the most common causes of dehumidifier leaks and how to fix them quickly.