When we consider what issues might befall a boat, excess moisture might not be our first thought. After all, these vessels are engineered to thrive in an environment characterized by its abundance of water. But while every due care and attention is provided to ensure the hull of the boat is watertight, the effect of airborne moisture is often overlooked.
Boats are particularly vulnerable to airborne moisture, as the sea air is ordinarily humid. When this warm, moist air meets the cold surfaces of the boat, you’ll soon be left with pools of condensation (similarly to how high humidity can affect your car or RV). The issue with humidity is only made worse when factoring in onboard activities, such as cooking, washing, and even breathing or perspiring.
If left unchecked, excess moisture can wreak havoc on your boat. First and foremost, you will notice the effects on the interior. Mold and mildew will quickly spread and furnishings and belongings will be laid to waste. The issue is then exacerbated when we consider potential rust and damage to electrical components.
As any boat owner knows, keeping on top of the maintenance is no easy task. But thankfully, investing in a dehumidifier offers an easy solution to protect your boat from excess moisture. By drawing the warm, moist air into the dehumidifier, it is then rapidly cooled, resulting in any water vapor being separated and collected in the internal reservoir, leaving cool, dry air to be redistributed.
To help you in your search for the right dehumidifier, we’ve put together six excellent solutions, across a range of budgets, tank sizes, and even different power supplies. Each of our recommended dehumidifiers has been analyzed through Consumer Reports and Fakespot, to help us determine which machines will be best suited to life at sea. Each option comes with glowing reviews from the genuine people that use them, so you can rest assured your boat will be in safe hands. So without further ado this is our list of the best dehumidifiers for boats in 2022.
Last update on 2023-04-02 / Affiliate links / Images from Amazon Product Advertising API
1. InvisiPure Hydrowave Dehumidifier
A dehumidifier for a boat needs to be compact, have low power consumption, and be able to be left unattended. The InvisiPure Hydrowave gives you all of this in a budget-friendly package.
Measuring 9.8 x 6.1 x 13.9 inches, the unit is incredibly easy to find a place to set up. If your boat isn’t on the water constantly, you may not need ultra high-volume dehumidification, and this unit pulls 1.7 pints a day. That’s enough to effectively keep most small to mid-size boats within the optimal humidity range of under 60% relative.
This unit uses Peltier thermoelectric technology rather than the standard compressor, making it extremely lightweight. This allows you to easily set it up on a shelf or even leave it on a counter. It keeps the power draw to an incredibly low 75 Watts, so it won’t drain your boat’s battery rapidly. It also has a 2-prong plug, so it’s not a problem if your boat doesn’t have grounded sockets.
If you need to move the unit around your boat, there’s an integrated handle on the back to allow you to easily pick it up with a single hand. It also has a 5-foot power cable, giving you a little flexibility to reach power from where you need it.
The unit draws air in through the back through an included washable filter. Once the Peltier Technology removes the moisture, the dry air is then pushed out through the dual air out vents on the side. Being the unit doesn’t use a compressor for dehumidification, it doesn’t produce as much heat as its competitors.
There’s a single control on the back to turn the unit on and off. The moisture collects in a 0.5-gallon reservoir that inserts into the back of the unit. The size of the reservoir means you’ll only have to empty the unit every two days at the most frequent. It also features an automatic shutoff to prevent the reservoir from overflowing.
- Tank Size: 0.5 gallons
- Room Size Suitability: 300 sq. ft
- Weight: 5.7 lbs
- Special Features: Automatically shut-off, Continuous drain function
What we love
- The condensate reservoir is a transparent blue so that you can easily keep an eye on the water level
- You can purchase and attach a 3/8-inch drain line for continuous drainage
- The condensate reservoir has a cover to help prevent spills while emptying
- The fact that there’s no compressor means the unit is ready to start as soon as you set it up, you don’t have to wait for the refrigerant to settle
We don't like this as much
- The unit operates on a continuous basis, it does not have automatic humidity controls
- We’d like to see the reservoir located on the front of the unit for easier access
2. Ivation IVADM45 Dehumidifier
Ivation has produced a compact, low-power consuming dehumidifier that’s perfect for boats. The IVADM45 measures only 8.6 x 7 inches and stands just under 14 inches tall, making it perfect to set on a shelf, counter, or table.
The unit uses Peltier thermoelectric technology, so there are no moving parts and it is incredibly quiet. It also makes it very efficient on power consumption, rated at only 72 Watts. You’ll have plenty of flexibility where you set the unit up on your boat with the nearly 11-foot power cable.
There are only three controls on this unit, the power switch on the back, and the buttons to control the humidistat on the front. The automatic humidistat enables this unit to automatically turn on and off to maintain your desired humidity level. The humidistat’s range is between 40% and 80%, adjustable in 5% increments.
As it runs, it’ll remove up to 1.5 pints of water from the air every day, emptying into a 4-pint reservoir located on the back. The reservoir is large enough you’ll only have to empty it about every 2.5 days. If you happen to forget to empty it, the unit has an automatic shutoff to prevent overflowing. There’s also a yellow indicator light on the front to alert you to it being at capacity. When you need to empty the reservoir, there’s a molded handle on the bottom to make it easier to pull out.
The unit brings air in through the intake on the back of the unit, with dual air outputs on the sides of the unit. If you need to move the unit around your boat, there’s an integrated handle on the back.
- Tank Size: 4 pints
- Room Size Suitability: 100 sq. ft
- Weight: 6.7 lbs
- Special Features: Humidistat to automatically control the unit for your desired humidity level
What we love
- The power cable is removable, making it easier to store the unit in the off-season
- The brushless motor for the fan makes the unit run nearly silently
- You can easily empty the reservoir without making a mess thanks to the reservoir cover
- The two-prong plugs can more easily be used with older boats that aren’t wired for ground
We don't like this as much
- The unit does not come with a continuous drain feature, so you have to stay on top of emptying the reservoir
- We wish the reservoir cover was removable to allow for easier cleaning
3. ALORAIR HD55
Anyone who’s had a water problem on their boat knows how important it is to get rid of the extra moisture quickly. The best way is with a high-capacity industrial dehumidifier like the ALORAIR HD55. This unit removes a massive 55 pints of moisture per day according to the AHAM rating. However, when it’s operating at maximum saturation, it’ll take out a massive 120 pints per day. It’ll circulate up to 130 cubic feet of air per minute, so as long as your boat is less than 1,300 square feet, it’ll take care of your moisture issue quickly.
The unit measures 19.2 x 12.2 x 13.3 inches, and weighs in at a hefty 57 lbs. It relies on a gravity-driven draining system, so the unit will need to be elevated on a counter, sturdy shelf, or table near a drain or window. Just be sure the unit is positioned higher than the drain to ensure you have proper draining. It comes with robust handles mounted to the top of the unit to help you with moving and placing it where it’s needed.
It has a tremendous operational temperature range, from 36 degrees up to 104 degrees Fahrenheit. Whether you’re dealing with a hull leak in the summer or a roof leak in the early spring or late fall, this unit is ready to take care of it. To keep the coils from freezing, it has an automatic defrost function, allowing it to continue working in low-temperature settings. You’ll be able to use the automatic humidistat to set your ideal humidity and have the unit shut off. You can set it for anywhere between 36% and 90% relative, in 1% increments.
It’ll also help remove unwanted contaminants from the air with the MERV-8 filter. When you have a water problem, this is especially important for removing mold spores from the air before they can settle and multiply.
- Tank Size: N/A
- Room Size Suitability: 1,300 sq. ft
- Weight: 57.3 lbs
- Special Features: The unit has internal corrosion protection with the rare earth alloys used for the evaporator tube
What we love
- The unit is quiet for being an industrial dehumidifier, rating in at under 52 dB
- You can get an optional remote control to be able to adjust the unit from on deck
- There are adjustable feet on the bottom to ensure the unit is level regardless of the tilt of your boat
- The power cable is a massive 10 feet, so it’ll easily reach the deck to connect to an extension cord
We don't like this as much
- We wish the unit came with a longer drainage hose
- There’s no condensate pump, so you have to keep the unit above a drain
4. Ivation 13-Pint Dehumidifier
If you’re looking for a different technology than a compressor or the thermoelectric options, you’ll want to check out the Ivation desiccant dehumidifier. This uses a desiccant wheel to absorb the moisture from the processed air moving through the system. It then uses heated air to dry out the desiccant wheel so that it can continue working.
This process means that the system is much quieter than other standard compressor-style dehumidifiers. It also means they are much less bulky, so they are easier to manage while dehumidifying your boat. For instance, the Ivation 13-pint desiccant dehumidifier has a footprint of only 10.6 x 6.9 inches, and stands only 17.5 inches tall. It also weighs only 14 lbs, substantially less than most compressor models.
This unit will remove up to 13 pints of moisture from the air per day to help keep your boat’s cabin fresh. It’ll drain into the included 0.5 gallon condensate reservoir, or you can connect the included drain line to use the continuous drain feature. The condensate reservoir also has a level indicator window so that you can see when it’s time to empty the tank.
This unit comes with safety features built-in that are perfect for use in an environment that moves. It has an automatic shutoff for when the reservoir fills so that you don’t have to worry about it overflowing. It also has an anti-tilt sensor, which will shut it off if it senses the unit tipping over. This protects the motors inside from overheating if it lands on the air intake side.
Unlike most units, the air intake is on the side of the unit, rather than the back. On the opposite side is the output vent, which offers a swinging vent. This feature allows the unit to adjust where the dry air is directed to get better coverage throughout the room.
- Tank Size: 0.5 gallons
- Room Size Suitability: 270 sq. ft
- Weight: 14 lbs
- Special Features: Simple and user-friendly LCD display and controls
What we love
- There’s an adjustable 12-hour timer if you know you want the unit to only run for a specified amount of time
- It comes with a washable filter that fits at the air intake vent to catch large airborne particles like hair and dander to protect the internal components
- It’s equipped with an automatic restart feature if there happens to be a power interruption
- The display shows you both the ambient humidity and the ambient room temperature
We don't like this as much
- The unit uses a large amount of energy for not having a compressor, up to 470 W on high
- Does produce some noticeable heat
5. ECOR PRO Dehumidifier
One of the greatest challenges with dehumidifying a boat is not having to worry about emptying the condensate reservoir to keep it running. The ECOR Pro solves that problem by evacuating the moisture it collects through hot water vapor rather than through condensed water.
This particular unit is another desiccant model. As the unit runs, the desiccant wheel collects the moisture. To dry it out, the unit utilizes a heater to then vaporize the water off the desiccant wheel and exhaust it out the back. To keep the moisture from reentering your room, you connect a maximum 2-foot hose to the 1.5-inch exhaust port on the back. You simply route the hose out a window or other exhaust port, similar to the exhaust of a portable air conditioner unit. It is the heater that accounts for the majority of the 400 Watts of power the unit consumes. Due to the amount of power it requires, you’ll want to run an extension cable from an off-board power source or bring on a generator.
This makes the unit extremely compact, measuring only 7.9 x 7.9 x 7.9 inches, and weighing less than 20 lbs. It is also quiet, giving off a mere 49 dB of noise, which is similar to moderate rainfall. The fully stainless steel housing makes the unit fairly robust for use on a boat. You won’t have to worry about removing it before you cast off if you don’t want to, it should be able to handle the movement on the water. It also has a mounted carry handle mounted to the top of the housing to make moving it easier.
You can expect this unit to remove up to 30 pints of moisture per day while cycling 53 cubic feet per minute of air. It also has an automatic restart to remove moisture from your boat when the power restarts.
- Tank Size: N/A
- Room Size Suitability: 500 sq. ft
- Weight: 13.62 lbs
- Special Features: The unit is fully self-regulated so that it only runs to maintain your desired humidity level without wasting energy
What we love
- Unlike most dehumidifiers, this unit can be mounted in any orientation, including on its side and upside down
- It will continue to operate down to an incredibly low -4 degrees Fahrenheit
- The controls are simple with a switch for using a remote and a dial to set the humidistat
- It has an incredibly long 15-foot power cable giving you a lot of placement flexibility
We don't like this as much
- You need to connect a vent hose to prevent the moist “regen” air from reentering your space
- Changing fan modes requires removing the cover and accessing the internal components
6. Better Boat 2 Pack Boat Dehumidifier
Occasionally, you need just enough humidity control to help reduce musty smells over the off-season. This is when a chemical moisture absorber comes in handy, like the Better Boat boat dehumidifier. The beauty of these products is that you don’t have to worry about it draining your boat’s battery or running power to it.
This particular version is compact, with a footprint of 5 x 3 inches, standing only 5 inches tall. You can easily set this up on a port sill, table, counter, shelf, or even just the deck of your boat’s cabin. Simply remove the foil seal, and set it out, and it’ll start doing its job.
Usage length varies based on the amount of ambient moisture. In high humidity areas, it may need replacing every couple of days. However, over the colder, drier months, it may last two months or more.
It uses a proprietary chemical absorption mixture, which usually consists of materials like silica, sodium chloride, potassium chloride, calcium chloride, dry sorbitol, or xylitol. This particular product also uses activated charcoal to help remove musty odors as it works to remove moisture. Depending on the size of your boat cabin, you may want to use more than one for better coverage. If your boat has a head, you’ll want to be sure to put one in there.
You don’t have to worry about spills with this particular unit. The bucket is semi-transparent, allowing you to see when the crystals are dissolved. It has a spill-resistant safety mesh filter to help prevent spills when it needs replacing.
- Tank Size: N/A
- Room Size Suitability: 250 sq. ft
- Weight: 1 lb
- Special Features: It requires no power to help control the moisture in your boat
What we love
- This is the easiest product to use to help control musty smells
- You don’t have to worry about emptying a unit to keep the product working day after day
- It creates absolutely no noise and is small enough to go unnoticed when entertaining
- It helps reduce the development of mold and mildew in your cabin
We don't like this as much
- There is no way to control the amount of moisture this product pulls from the air
- You have to check on it frequently to see if the crystals have dissolved, indicating it requires replacing
FAQs about Dehumidifiers For Boats
Why is it important to have a boat dehumidifier?
Marine environments are naturally more humid being on the water. Regardless, that extra humidity can still wreak havoc on the interior cabin of your boat. This may start as a musty smell that’s just unpleasant when you enter the cabin. The musty smell indicates you have a problem with mold growing somewhere.
Mold and mildew grow best in warm and moist environments. Running a dehumidifier keeps the humidity within the range that discourages this development, preventing water damage like swollen particleboard, and keeping all cloth materials fresh.
What should I look for in a boat dehumidifier?
There are several things that good boat dehumidifiers have in common. The best dehumidifiers for boats have an automatic humidistat to control the moisture in the room. This prevents the unit from continuing to run once you’ve achieved the right humidity level, saving you money on energy, and wear on your unit. Next, consider units that have a continuous drain feature so that it doesn’t stop running or risk overflowing. Finally, look for dehumidifiers which can be left running for long periods without risk to the dehumidifier’s function. Check your owner’s manual or unit details to ensure the unit can run for more than 24 hours without a required shutoff period.
What factors should I consider when choosing a dehumidifier for my boat?
First, consider the size of the cabin you’re attempting to treat. If you have a large cabin, you don’t want a unit that’s for small spaces.
You’ll want to consider what the dehumidifier is made of, especially if it’s a compressor-style unit. Coils are notorious for corrosion, especially with some of the conditions you find on a boat on the water.
Finally, consider how much moisture you will need to remove per day. Just because a unit is rated for a certain size room, it may not work for high humidity areas if it’s made for low humidity environments.
Which dehumidifier is best for you?
Getting the right dehumidifier for your boat is important to keeping your investment in good condition over the long term. It’ll reduce musty smells, but keep both the contents and the structure safe from mold.
The best humidifier for your boat depends on several factors. You’ll want to match the serviceable area and the amount of moisture you need to remove from the air. You’ll also want to keep an eye on the material the unit is made of to ensure it’s resistant to marine environments.
Beyond that, you’ll want to consider what will happen with the moisture you remove from the air. Will the unit need emptying, or will it use a continuous drain, and where is the drain compared to where you plan to set the unit up?
Of high importance is also the amount of power the unit will draw, and when do you plan to run it? If it’s a high draw unit, say over 500 Watts, and you plan to use it while on the water, will your boat’s system be able to handle that much? Moreover, consider the length of the unit’s power cable so that you can ensure you can plug it in without leaving extension cords all over.
Finally, there is budget. For boats, the most expensive dehumidifiers aren’t always the best for marine environments. However, the lower the budget, the less you should expect from your unit. The following are our recommendations based on room size and what’s included.
- Budget/Smaller Boats –Better Boat 2 Pack Boat Dehumidifier
- Medium Sized Boats – Ivation 13-Pint Small-Area Desiccant Dehumidifier
- Larger Boats – ALORAIR Basement/Crawl Space Dehumidifiers