Keystone 30 Pint Dehumidifier

One thing you may never have considered when purchasing your RV was a dehumidifier… let alone what would be the best RV dehumidifier on the market.

An RV is essentially a temporary living quarters on wheels. As such, it makes sense that the air quality inside one will not always be perfect.

Since many people use RVs for long traveling vacations, you could be living inside it as much as you would inside your own home. If you have a humidifier in your home then you can understand why it would be even more important to want an RV dehumidifier.

Humidity and RVs go together. This is because they are in the elements when not locked up in storage. On top of this, when exposed to the environment, it is usually for long periods of time.

Other major factors that can contribute to the buildup of humidity inside an RV include:

  • cooking,
  • washing, and
  • changes in the outdoor temperature compared to the interior temperature.

Dampness in the air can increase in these situations. This can promote the creation of rust on the outside, and structural damage and health issues from mold or mildew on the inside.

Below are our picks of the best dehumidifiers for RV use in 2020, which we will also look into in more detail later in this article…

ImageTitleRatingMore Info
Keystone 30 Pint DehumidifierKeystone KSTAD30B 30-Pint Dehumidifier

4.4 out of 5 stars
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Eva-dry Edv-1100 Electric Petite Dehumidifier.jpgEva-dry Edv-1100 Electric Petite Dehumidifier

3.8 out of 5 stars
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Eva-dry E-333 Mini Dehumidifier.jpgEva-dry E-333 Mini Dehumidifier

4.1 out of 5 stars
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H2Out Space DryersH2Out Space Dryers

4.2 out of 5 stars
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Using An RV Dehumidifier And Hygrometer

You can use a dehumidifier to regulate the humidity, or moisture content, in the air. Usually, damage can occur through the formation of corrosion or mold if the humidity is too high. You use a dehumidifier to bring that level down.

Anywhere between 40 and 60-percent humidity is safe and comfortable to prevent corrosion and mold. A dehumidifier controls this by pulling the moisture out of the air and converting it to liquid water.

The water is then collected in a bucket or container built into the dehumidifier, or removed via a connected hose. Once the collection bucket is full, you can remove it, empty and replace it

This is how you can manage the humidity level at an acceptable level in living spaces. The best small dehumidifier models are used for this purpose not only in RVs, but also in basements, closets, bathrooms, sheds, and garages.

A hygrometer is an instrument you may want to have mounted in your RV at all times. This will track the moisture content in the air and is an easy way to tell when you will need to use your RV dehumidifier.

You can use the hygrometer to determine the dryness (low humidity) or dampness (high humidity) inside your RV. It will give you an understanding of what activities inside your recreational vehicle have an impact on the moisture content. It will alert you when the level gets too high or too low.

Most dehumidifiers and humidifiers have these instruments built-in. However, a separate stand-alone hygrometer may be useful depending on how often you use your RV.

For more information on some of the best hygrometers on the market, make sure that you check out this article.

Signs You Need An RV Dehumidifier

You need to be observant of changes taking place inside your RV. For example, if the windows often have excessive condensation, you will need to install a cheap dehumidifier. Also, if the floors or walls of the RV feel damp in any way, you need a dehumidifier.

Besides being attractive to mold and mildew, high humidity will attract termites and various other insects.

The use of an RV dehumidifier will regulate the moisture content to safe levels for you and your vehicle.

The Different Types Of Dehumidifiers For RVs

There are many different types of dehumidifiers for RV use. They are categorized as electric (110V or 12V) and non-electric.

The electric type requires access to a power source.

Non-electric dehumidifiers are popular with RV owners. They fall into two different categories. They are identified as:

  • ‘bucket’, or
  • ‘reusable’

and are easy to distinguish from each other.

The bucket dehumidifiers use water-absorbent crystals in a bucket to regulate humidity. Once the crystals have been completely saturated with water, they need replacement.

The reusable dehumidifiers use silica gel crystals to draw water from the air. Once saturated, you can remove the water from the gel often by placing it in an oven to dry out.

By comparison, electric RV dehumidifiers need far less attention than non-electric. However, they do need an electricity supply to operate and also need more space.

110 or 12 Volt Dehumidifier For Your RV?

The electrical system on an RV is likely comprised of actually three different electrical systems. They fall under two main categories:

  • the 12 volt DC systems, and
  • the 110/120 volt AC coach system.

Your RV battery is responsible for keeping the 12 volt systems operational. The 110/120 volt system is used when you plug your RV into a power source or use a gas-powered generator.

The 12-volt systems actually break into two different systems. These are:

  • the automotive system, and
  • the coach system.

The automotive system is the same basic one that is in your car and operates all the essentials you need to use your vehicle from headlights to power windows and so on. The coach system, however, runs all the low-voltage 12V items in the RV living area, such as fans, overhead lights, stereo, etc.

So all we are going to look at here are the 12-volt coach system and the 110/120 volt system.

The 12 Volt Coach System

Your RV batteries are what keep the 12-volt coach system operational and that allows you to use many of the appliances that are on board your motorhome. As mentioned above, this includes items such as the furnace fan, lights, stereo, water pump, etc. If you have a 12V dehumidifier, you can also run this on the 12-volt coach electrical system.

In order to keep the 12 volt DC system operating smoothly, you must keep the batteries fully charged. You can do this in one of four different ways. You can charge them with solar power, with a generator, with your engine running or with the assistance of a campground hookup (see below).

The 110/120 Volt System

The 120-volt electrical source you access with your RV is usually supplied when you park at an RV campground that offers “all services” and that typically refers to such extras as power hookups, a sani dump, and whatever other creature comforts are available at that specific campground.

The cord you use to plug into the power source will be a heavy-duty one supplied by the RV manufacturer and your vehicle will typically have either a 30 or 50 amp system. By plugging into the outside source, you are able to provide AC power to the RV. This means that you can use the higher-power appliances such as microwave, air-conditioner, fridge (when in electric mode), and pretty much anything else that plugs into a “normal” electric wall socket.

The 110/120 system will convert the power to charge the 12V batteries, and allows the items requiring 12-volts to operate.

If you are specifically looking for a 12v dehumidifier for RV use, they do exist, but there are not many. You would be better off using one that uses the 110/120 volt power system.

Features To Look For In An RV Dehumidifier

There are quite a few different styles and features that you may want to consider before buying an RV dehumidifier. They include:

Desiccant or Refrigerant?

There are two different types of dehumidifiers. They fall under two distinct categories.

A desiccant is rechargeable and is best suited for small, confined areas. For a localized moisture problem, a desiccant is the most effective dehumidifier to combat this.

A refrigerant dehumidifier is a larger style unit and can provide mold and moisture control for bigger areas ranging from the entire interior of your RV, up to the size of your house. The refrigerant style requires power to operate and pulls moisture from the air with coils that collect and convert the moisture to water that is collected or drained from the unit.


A 12v dehumidifier for RV use is actually not very efficient, and are harder to come by. As such, it is usually a better choice to get a higher power 120V unit. The main problem with a 120V dehumidifier is that, when you are off the beaten track, you may not be in a campground with access to mains power.

When traveling, a larger dehumidifier would provide more efficiency than a desiccant. However, desiccant dehumidifiers work very well when the RV is not in use – stored away for the season for example.


The amount of noise produced by a dehumidifier is typically in direct relation to the size of the unit. For example, medium and large dehumidifiers will generate noise levels of between 55 and 67 decibels when at full power. Smaller dehumidifiers will produce less noise but they will produce some noise.

Desiccant dehumidifiers, or those that use Peltier Technology such as the Eva-Dry EDV-1100, are silent but don’t draw as much moisture from the air.


The moisture collected from the air is converted to water and it is collected in a tank in many non-desiccant dehumidifier models. The tank is designed to be removed so that it can be emptied but there are also different size tanks that relate to the rating of each.

Dehumidifiers are rated on how many cubic feet per minute they can collect moisture from the air. As a very rough guide, the larger the tank capacity, the higher the cubic feet per minute (CFM) rating. Tanks can be between 10 and 75 pints (the larger ones for residential use).

Power Consumption

Desiccant and Peltier Technology dehumidifiers use less power than refrigerant styles. To get a better sense of the amount of energy this can translate to, a refrigerant dehumidifier would use about the same amount of energy as a refrigerator.


The moisture collected by dehumidifiers is typically collected in a removable tank. The tank is then manually emptied and replaced. The size of the tank, how long you run the dehumidifier and the humidity level will all factor into how quickly a tank will fill and require emptying.

Larger units have drain hoses that can be fed into RV drainage locations such as a sink or shower if so desired.


Most dehumidifiers have either an alert system or an automatic shut off that turns off the unit once the tank is filled to capacity. Other units have built-in timers so you can control when the dehumidifier is in operation shutting it off when it is no longer required.


A humidistat is a control that you use to set when you want the dehumidifier to go on or off. It typically operates on a range of humidity levels that it recorded inside the unit with an onboard humidistat. Higher-end models allow for more precise humidity level settings and give you control over the amount of humidity you are prepared to have before reducing it with the dehumidifier.

Our Picks of the Best RV Dehumidifiers on the Market

With these points in mind, we have selected some of the best RV dehumidifiers on the market. Factors that we considered include:

  • how well they work,
  • price,
  • features, and
  • user-friendliness.

Keystone KSTAD30B 30-Pint Dehumidifier

Keystone 30 Pint Dehumidifier

This is one of the best cheap dehumidifiers you will find and it is still one of the most efficient. It is EnergyStar rated to eliminate up to 30 pints of moisture daily and capable of working that magic in spaces up to 1,500 square feet. These factors make this one great option as an RV dehumidifier.

There are multiple settings (Normal, Turbo plus Auto-Defrost) and the dust filter is removable and easy to clean. Also, the unit has a built-in alert to tell you when the dust filter requires cleaning.

What makes this one of the best small dehumidifiers is that you can hook it up for continuous drainage by adding a hose.

Feedback and reviews give this product great ratings although some find it a little noisy, especially for a confined space. A few have reported having leaking issues and that the removable water bucket was not as easy to remove as it should be.

Aside from these points, as with all Keystone dehumidifiers, this RV dehumidifier is powerful and does an excellent job.

Click here for more information on the Keystone KSTAD30B 30-Pint Dehumidifier.


Quiet operation
Compact size fits in tight places
Works effectively to control moisture content


Some users noted the unit was smaller than they expected
Depending on your set up, this product may use more power than expected
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Eva-Dry EDV-1100 Petite Dehumidifier

Eva-Dry EDV-1100 Petite Dehumidifier

Any RV dehumidifier that uses Peltier Technology in the design is well worth a look as that means it will be very quiet. The Peltier system has no compressor… the result is what the manufacturer likes to refer to as being “Whisper Quiet”.

The size of this unit is compact so you can tuck it away just about anywhere. In an RV where space is a premium, this means it will not be in the way.

The water reservoir will hold up to 16-ounces and is easy to remove and empty. There’s even an indicator light that will inform you when the reservoir is full and in need of an emptying. It will also shut off once the tank has reached its capacity.

The design of this dehumidifier without a compressor means low energy consumption. The compact size, energy efficiency and simple operation all earn our praise.

The speed in which this dehumidifier can regulate relative humidity in your RV is one key feature why this product is so popular.

Click here for more information on the Eva-dry Edv-1100 Electric Petite Dehumidifier. Also, make sure to check out the short video below…


Operates very quietly
Designed to be compact for use in small areas
Powerful in reducing moisture


Effective operation but may take considerable time to make a difference
Stopper on the tank is difficult to remove/replace.
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Eva-Dry E-333 Mini Dehumidifier

Eva-Dry E-333 Mini Dehumidifier

This lightweight and compact RV humidifier weighs in at only 1.2-pounds. It can take control of the humidity in a space up to 333 cubic feet with no problem and no power. This product is 100-percent renewable and the manufacturer says it will last up to ten years if properly taken care of.

As it is eco-friendly and works without batteries or electricity, there are no cords to mess around with. It is the ideal choice for various applications ranging from:

  • RVs,
  • gun safes,
  • bathrooms,
  • boats,
  • laundry rooms

and anywhere else you need to take control of moisture to fight mold and mildew build-up.

Reviews of this best small dehumidifier give it top marks. The portable size and long life of the silica gel (provided you recharge it when required) are the most frequent features noted. It will work in a lot of small spaces which makes this one of the better cheap dehumidifiers on the market.

Click here for more information on the Eva-dry E-333 Mini Dehumidifier. Also, have a look at the short video below…


Nice, compact size
Viewing screen helps determine when beads are dry or wet inside
Easy to recharge by just plugging into a wall outlet


Works effectively only in very small spaces
Some beads may escape from the back of the unit when being recharged
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H2Out Space Dryers

H2Out Space Dryers

This RV dehumidifier is a non-toxic, non-corrosive desiccant style unit. This means that it does not use electricity to operate.

Because it uses what the manufacturer calls a “blue media”, once that turns pale pink, it is due for a recharge. This can take up to two months before you have to recharge.

All you do to recharge is heat the product in an oven for about an hour at 300-degrees F. Heating in the oven completely dries out the content that collects moisture and makes it reusable.

This particular dehumidifier is for small spaces. This makes it suitable for use in closets, bathrooms, kitchens, RVs, gun safes, and similar size quarters.

It receives good marks with varying levels of success reported by users depending on where this dehumidifier is used.

Click here for more information on the H2Out Space Dryers – SD100 Series, and see it in action in the video below…


Works well in small spaces
Easy to use


Recharging instructions are not clear
Can only work in very small spaces
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Last Words On RV Dehumidifiers…

We all know how dangerous too much or too little moisture in the air can be. It can be harmful to not only our vehicles but it can be harmful to our health as well. That is why RV dehumidifiers are an important part of life on the road.

If you are going to spend a long time on the road, then you don’t want your RV to make you sick. You also don’t want your RV to get damaged through corrosion or mold infestation.

Controlling the dampness in your recreational vehicle is simple with the use of any of the products reviewed here. Each one of these best small dehumidifier options has features that can provide you with effortless moisture control. They are easy to use so they will not disrupt your holiday plans.

There are some great cheap dehumidifiers around nowadays. So before you plan your next road trip, be sure to include the best RV dehumidifier on your shopping list.

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