Why Is My Dehumidifier Leaking Water? And How To Fix It

A lot is going on inside your humidifier. When all is working well, these parts work together to create a safer, more comfortable environment inside your home. But when they stop working and start leaking, you end up with a puzzle that can be very difficult to solve.

There are a dozen reasons why a dehumidifier might start leaking. Figuring out the cause can be a frustrating process but allowing the issue to continue is downright dangerous. All that extra moisture can ruin flooring and provide the perfect environment for bacteria, odors, and mold to breed.

Is your dehumidifier leaking? Then you’ll want to keep reading. Below, we have outlined the top twelve reasons why dehumidifiers leak and provided simple solutions to fix the problem for good.

woman fixing a leaking dehumidifier

Disclosure:It is important you understand that we may receive commissions when you click our links and make purchases. However, this does not impact our reviews and comparisons. All opinions are our own we pride ourselves on keeping our articles fair and balanced. For more info see our disclosure statement.

13 Reasons Why Your Dehumidifier Is Leaking Water & How to Fix it

Before we begin troubleshooting your leaking dehumidifier, it is important that you understand how to use your appliance properly.

There are a lot of simple operational errors that can cause leaks. You can avoid many problems by assuring your dehumidifier has been set up properly, programmed to the optimal setting, and placed in the best location.

If your dehumidifier is new, take a minute to read our article on How to Use a Dehumidifier. This article will tell you everything you need to know to get started with your new appliance.

For those with older appliances or issues unrelated to improper setup, keep reading to find out the twelve most likely causes for dehumidifier leaks and how to solve them.

1. Misaligned Water Collection Bucket

a misaligned water collection bucket can cause your dehumidifier to leak

Portable dehumidifiers and those not built into the home all have a removable water collection bucket. This bucket is needed to catch water when a drainage hose is not in use.

If this bucket is inserted incorrectly or is knocked out of place, it can cause the unit to leak.

To fix a misaligned water collection bucket:

  1. Unplug the appliance.
  2. Open the reservoir compartment to reveal the water bucket.
  3. Remove the water bucket and empty any water inside it. You may also need to wipe down any water pooling on the inside of the unit.
  4. Carefully replace the water bucket according to the directions that came with your unit.
  5. Assure the bucket is level, locked in the correct position, and that the overflow switch (usually a floating device that sits in the bucket) is positioned correctly.

If this was the issue, you should not see any more water pooling below the unit once you have turned it back on.

Be sure to empty your water bucket frequently and keep the dehumidifier in a safe spot where it won’t be bumped to assure the problem doesn’t reoccur. 

2. Cracked Water Reservoir

a cracked water reservoir can cause dehumidifier leaks

As we mentioned above, a dehumidifier relies on a lot of different parts all working together. If you are unclear on how a dehumidifier works, it can be helpful to do some research. Our article, How Does a Dehumidifier Work, is a great place to start.

Sometimes the issue is as simple as one of these complex pieces breaking. The most likely candidate for this is the water collection bucket. In older units and those exposed to drastic temperature changes, the water reservoir bucket can crack, leading to leaks.

To check for leaks in your water reservoir:

  1. Unplug the appliance.
  2. Open the reservoir compartment to reveal the water bucket.
  3. Pull the bucket out and inspect it for cracks and blemishes. Some cracks may be too small to see, so it can be helpful to fill the bucket in the sink and watch for leaks.

If you find a leak in your reservoir bucket, your best option is to contact the manufacturer and order a replacement. It may be possible to patch the crack, but this may only be a short-term solution. Most likely, you’ll end up dealing with the same issue again in the future.

3. Blocked Hose

clogged dehumidifier drainage hose

If your dehumidifier is hooked up to a drainage hose, then the source of your leak may be a blocked hose. Debris can enter from the draining end, which is more likely to occur when you have it hooked up outside, where rodents and bugs have access to it. 

To check your drainage hose for blockages:

  1. Unplug the unit.
  2. Remove the drainage hose from where it connects to the unit.
  3. Take the hose outside and insert your garden hose into one end.
  4. Turn the garden hose on full blast and let the water run through until it comes cleanly out the other end.
  5. If the blockage doesn’t dislodge, try soaking the hose in a sink filled with hot soapy water then trying again.

If water runs through the hose without issue and nothing comes out, then your leak is likely not due to a hose blockage.

4. Bent Drain Pipe

A blockage isn’t the only reason a drain hose might leak. If the hose is kinked or bent, it can cause water to back up into the reservoir and leak onto the floor.

Your drainage hose pipe should lead to the floor drain or outside through the shortest route possible, and it shouldn’t have tight twists or turns. 

To check your drainpipe for kinks, follow its route from the back of the unit to the area where it drains. Look for any sharp turns or areas where the hose twists around itself. If you notice any of these issues, remove your drain hose, reposition it to flat, and reconnect it.

You may need to use stabilizers or objects to hold the hose in place and widen any turns to prevent the kink from reoccurring.

5. Small Water Pipe

Sometimes the problem has less to do with the hose being kinked and more to do with the fact that the drainage hose diameter is too small to handle the output of your humidifier.

In very humid environments, it’s possible for the appliance to produce water faster than the drain hose can accommodate, causing the water to back up into the unit. You can assume this is the problem if you see a continuous, powerful stream of water coming out of the drain hose and the appliance is still leaking.

Depending on your dehumidifier, this may or may not be an easy fix.

Most large dehumidifiers have a ¾” drainage hose hookup. These can accommodate hoses as wide as your standard garden hose. But often, these units come with very slim hoses that utilize a wide hookup. If you are using one of these small-diameter hoses, try switching it out for a wider option and see if that relieves the issue.

Some portable and personal dehumidifiers have smaller hose hookups, usually ½” diameter or less. If this is the case for your unit and you believe a small hose is the issue, your best option will be to purchase a new dehumidifier rated for use in more humid environments.

This EnergyStar informational article provides a useful capacity chart to help you find the right product for your needs.

6. Loose Hose Fitting Cap

Even if your hose is adequate for draining your dehumidifier, it can still leak if all the connection points are not secure.

If you notice a leak at the fitting cap where your hose connects to the dehumidifier, this is most likely your problem.

To fix a loose hose fitting cap:

  1. Unplug the appliance.
  2. Remove the drainage hose.
  3. Clean the fittings on the unit and the hose.
  4. Many units include a rubber o-ring that fits into the female end of the connection. If this is missing, purchase a replacement.
  5. Reattach the hose and tighten it until it stops turning, being sure to keep the fitting from cross-threading.
  6. If the fitting is still leaking, you may need to apply some plumber’s tape and re-tighten it.

If the fitting continues to leak, most likely, the issue is a bad fitting. You will need to order a replacement hose from the manufacturer if this is the case.

7. Drain Hose Coiled Vertically 

proper way of connecting hose to a dehumidifier

Most personal and portable dehumidifiers rely on gravity to move water from the tank out the drain hose. If there is any vertical lift of coiling in the hose, the water will back up into the unit, causing a leak.

If there is vertical coiling in your hose, you will need to secure the hose to the floor or at the endpoints to keep it flat and straight.

If there is a vertical gain in the hose between the unit and the drainage point, you will need to correct it. The easiest way to do this is to raise your dehumidifier off the ground using a few stacked boards, cinderblocks, or a table. Alternatively, you could place the unit on a shelf or counter.

If it is impossible to place the dehumidifier higher than the drainage point, you will need to install a drainage pump. Some units are built for this option, in which case the manufacturer should sell the right pump for your setup. For other units, you will need to add a general-use condensate pump to the drainage system.

8. Disconnected Drain Hose

disconnected drain hose can cause the dehumidifier to leak

It may seem like an obvious issue, but more often than not, a leaking dehumidifier is caused by a disconnected drainage hose. For new units, this often occurs because the drainage hose was never hooked up in the first place.

But it is also possible for a functioning hose to become disconnected or loosened over time. This is especially likely if the hose is exposed to fluctuating temperatures.

Before attempting more involved fixes, always check the drainage hose connection at the back of the unit and assure the end of the hose is secured over a floor drain or outside.

9. Hose Is Too Long 

Horizontal gain can also be a problem for pumpless humidifiers. If the drainage hose is too long, water can collect and back pool into the unit, causing leaks.

Long hoses are often a problem for dehumidifiers used in basements because the drainage point is often far away from the unit.

Buying one of the good quality dehumidifier for your basement can save you from this headache. These units have special features that make them optimal for use in sub-ground levels of the home, including built-in pumps that can drive water against gravity for proper drainage.

If you already have a leaking dehumidifier because the hose is too long, you have three options to mitigate the issue. You can move the unit closer to the drainage area, purchase a pump as described in the vertical coiling section above, or buy a new dehumidifier that is powerful enough to use in a basement setting.

10. Jammed Pump

If your dehumidifier has a pump but is still leaking from an overflowing water reservoir or drainage hose, you might have a jammed pump.

These pumps most commonly fail because they get jammed with debris.

To fix this issue:

  1. Unplug your appliance and pump.
  2. Remove the pump.
  3. Clean the pump as described in the manufacturer’s directions.
  4. Replace the pump and plug everything back in.

Be sure that the pump is installed properly. Many pump-containing dehumidifiers feature sensors that automatically stop the pump from functioning if the hose is not connected correctly or the pump isn’t in place. 

Your leaking issue should be fixed as long as everything is where it should be and the pump is free from blockages.

11. Frozen Coils

Frozen dehumidifier coils can happen for many reasons. And all can cause leaks to occur.

The most common cause is that the unit is operating at low temperatures. Any ambient temperature below 65 degrees can cause dehumidifier coils to ice up. Many dehumidifiers have a built-in thermometer that shuts the unit down if the temperature drops too low. If your unit doesn’t have this feature, you’ll have no choice but to turn it off manually. 

Problems with parts inside the dehumidifier can also cause the coils to freeze. If the fan motor or blower wheel goes out, there won’t be enough airflow to keep the coils from getting too cold. You will know this is the problem if you can’t hear the fan turning while the unit is working.

Other possible causes include a malfunctioning humidistat, thermostat, or bi-metal thermostat. Reference your owner’s manual for information on these parts and how to test if they are functioning properly.

12. Malfunctioning Overflow Switch 

picture of a working overflow switch

Modern dehumidifiers feature an auto-off function that will shut the unit down when the water collection bucket reaches capacity. If this feature is broken, your unit can overfill and overflow while in use.

So, if the leak is sudden and continues to worsen when the machine is operational, you can blame a faulty overflow switch. 

The most common setup for dehumidifier overflow switches involves an attached floaty that rises with the water in the collection bucket. Once the water reaches the maximum level, the rising floaty activates the switch and turns the unit off.

This switch can malfunction in many ways.

Often, the issue is as simple as the overflow floaty not being properly installed or reset after the water bucket is reinstalled. Reference your owner’s manual to check the proper placement and positioning of the overflow switch.

It is also possible for this switch to burn out or break. If this happens, you will need to order replacement parts from the manufacturer or buy a new dehumidifier.

If your appliance will be used in a very damp environment or run continuously, you can reduce the strain on the overflow switch by buying a high-capacity humidifier like this 50-pint unit from HomeLabs.

13. Blocked Drainage 

clogged drainage pipe

Blocked drainage hoses aren’t the only drainage blockages that can cause leaks in your dehumidifier. If the drain that your hose runs to is blocked, then it can cause water to build up, which will, in turn, cause water to collect in your dehumidifier.

Gravity-draining dehumidifiers require negative pressure to move water out of the unit and into the drain. If the end of the hose is sitting in standing water, it will exert pressure on the system, preventing the water from moving out.

The solution to this is often as simple as raising the hose, so the end does not sit in standing water. But if a blocked drain causes standing water, then you will need to get a plumber out to clear the drain before you can fix the leak in your dehumidifier.

Dehumidifier Spare Parts

If you have found a broken or fault component in your dehumidifier then you may need to replace it.

Sears Parts Direct has a wide range of parts for various dehumidifiers – as well as other home appliances!

Fix Your Leaking Dehumidifier

There are a lot of reasons a dehumidifier can leak. Most often, the issue is as simple as an improperly installed collection bucket or loose hose fitting. But other causes can be harder to diagnose and fix, including malfunctioning fan parts, broken overflow switches, and vertical or horizontal gain issues.

Are you having trouble diagnosing the cause of your dehumidifier leak? Comment below and let our home experts help you out!

About The Author

Aaron is the founder of and Essential Home and Garden. He likes to spend his spare time with his family, and doing DIY projects in the home and garden.

Leave a Comment