12v Dehumidifier: A Must Have Item For Boaters

Damp and humidity are the nemesis of boat owners and must be kept in check and under control, but it doesn’t have to be that way as there is something that you can do to help you in the fight to keep it at bay.

Whether your boat is in use or being moored for long periods a dehumidifier or moisture trap will help you keep on top of any damp problems that may be caused by excessive moisture in the air.

Dehumidifiers for use on a narrowboat

Below we have put together 6 dehumidifier reviews to show just how many choices you have, from low wattage electric dehumidifiers to natural non energy using options.

1. Unibond Aero 360 2 in 1 Natural Moisture Absorber

This wonderful little option is brought to you by a name that we probably all recognise, Unibond and is a great solution for damp and moisture problems that occur on boats.

The Unibond Aero has 360 degrees of air circulation that will trap moisture efficiently and silently, but, it doesn’t just absorb moisture, it neutralises odours at the same time with the patented anti-odour agents contained within it. Requiring no energy source means this is the ultimate eco-friendly option.

Once the moisture is absorbed it converts into a salty brine which is collected in the tank below which features a no-spill mechanism, so should you knock it there is no need to panic. This unit is suitable for areas of 20sq meters and will last up to 3 months. Replacement tabs, like the unit, are readily available and very affordable.

2. VonHaus 12 Litre Per Day Electric Dehumidifier

Now for something a little more robust with this model from VonHaus, this is not only a very stylish option it is one that is capable of extracting up to 12 litres of water per day and features the option of ‘continuous drainage’ should you require it, as it comes supplied with an overflow pipe for a permanent drain.

Featuring an easy to use digital control panel that not only allows you to set the 24hr timer, but you can also actually decide on just how much moisture you want to take out of the air by setting the humidity level you are happy with, from anywhere between 40 and 80% humidity.

The unit will show on the display when the 2-litre collection tank is full and automatically shut off so you have no fear of flooding should you miss it and once emptied will auto restart. The VonHaus dehumidifier is on wheels and very portable, measuring W25.5 x D22 and 44.5cms in height.

3. Pro Breeze Portable Mini Dehumidifier

Brought to you by Pro Breeze, who you may not think of first when looking for electrical goods but a choice that has become ever more popular. This option is a wonderful small, compact and lightweight unit that will sort any humidity problems out that you may have and is specifically designed for use in small areas making them ideal as boat dehumidifiers.

The thermoelectric technology used in this model makes it eco-friendly with low power consumption and an option that is also extremely quiet when running. Capable of pulling up to 250ml of water a day from the atmosphere and with a .5 litre water collection tank that is quick and easy to empty and features auto shut off when full.

Measuring in at a mere 18 x 28 x 16cms this Pro Breeze portable mini moisture absorber is a perfect fit for use as a narrowboat dehumidifier and at a very affordable price.

4. PureMate Portable and Lightweight Mini Dehumidifier

Another very compact and lightweight portable moisture absorber that is very similar to the item above, unlike the compressor models this uses the thermoelectric cooling technology that does not require the compressor making it not only very quiet but eco-friendly with low power consumption and therefore energy-saving.

This will extract up to 250ml of water per day and has a reservoir capacity of 500ml and features the auto shut off when full with an indicator to inform you. This model is suitable for a room size of 15 square metres and measures just 18 x 28 x 16cms again one of the options that are suitable for use as a narrowboat dehumidifier at an affordable price.

5A. Kampa Damp Buster Moister Drain for Boats

Ok so this may not win any prizes for style but it is produced by Kampa who are renowned for their camping, boating and caravanning accessories.

Although very simple in design the calcium chloride crystals will do a great job in absorbing any extra moisture in the air and can actually collect approximately 3 times its own weight in water. The moisture is simply absorbed by the crystals, that will only require replacing about every 4 months, that then converts to a salty brine that is collected in the base ready to be disposed of.

5. MELOPHY Electric Compact Dehumidifier

How stylish is this lovely little compact and lightweight model from Melophy? But don’t let the size fool you as this unit can remove up to 450ml of moisture each day and has a detachable water tank with a capacity of 1 litre which is quick and easy to empty. Featuring the usual auto shut OFF and indicator light for when full ensuring there is leakage onto any surfaces.

With a one-touch switch design that makes it easy to operate along with ultra-quiet technology, and low power consumption of just 22.5w this option has everything going for it and more. Measuring in at 17 x 10 x 26.5 it is the ideal size for any area on your boat.

6. KONTROL Moisture Trap/Dehumidifier

Now for something a little different as it is more of a trap than a dehumidifier in the true sense of the word, but it will still do the same job for you. This is totally budget and eco-friendly and will help with the solution to excessive damp causing moisture.

There is not much that can be said really except that once the crystals have been placed this little trap can collect up to a litre of water with no worrying about it switching off or overfilling. The ideal solution to damp especially if you have to leave your boat moored for long periods or have a wardrobe or an area on the boat that is particularly prone to being damp or mouldy.


Now we have shown you some of the choices we shall go into a little more detail as to what a dehumidifier does and how it can work for you.

What is a dehumidifier?

Although they can be used for both personal comfort and health reasons a dehumidifier will come into its own if you have any problems with excessive moisture that is causing damp, mould or mildew. By running a dehumidifier you can reduce the humidity level, extract the moisture and eliminate the risk of damp etc. which can not only damage the boat but can also cause health problems from the mildew spores.

Ok, so you already knew that bit but there are some that do misunderstand the exact job boat dehumidifiers do, with some believing that they will act as an air purifier.

Types of dehumidifier

There are two main types of dehumidifiers one being electric the other being non-energy using via the use of crystals.

Obviously, with the electric option, you will be using up your valuable energy supply but it will ensure that you have complete control over when and how often you need to use it, if you are unsure of your moisture levels then there are tools on the market that will tell you, such as damp meters that allow you to check your humidity levels quickly and easily, thus enabling you to prevent any problems rather than having to cure them.

When it comes to electric dehumidifiers there are two sorts that you can choose from.

Compressor Dehumidifiers

The compressor models work in a similar way to a fridge, as they draw the air in it is passed through a refrigerated coil which in turn causes the water in the air to condense and drip into the water reservoir below, the air is then warmed slightly and blown back into the room.

Although compressor dehumidifiers tend to be the most popular, especially in warmer temperaments, they do tend to be bulkier and a little noisier than the desiccant models. It is also worth noting that if the ambient temperature drops below 15 degrees they will freeze up and spend a lot of energy and time defrosting the coils rather than extracting moisture, thus rendering them extremely inefficient.

Desiccant Dehumidifiers

A desiccant dehumidifier is so-called because they use a desiccant material, a material that absorbs water, of which the most commonly used is Zeolite.

The built-in fan in the unit directs the airflow through a number of revolving wheels holding the desiccant material collecting the moisture and converting it to water in the chamber, as this type is using absorption they are particularly good for use in low temperatures.

Which is the best dehumidifier for your needs Compressor or Desiccant

So, if you are not going to be on your boat over winter but plan on, and have the setup, to have a dehumidifier running then the desiccant will be the type for you, due to the compressor models not being able to function properly at low temperatures they will ultimately turn themselves off.

If you are unable to use a dehumidifier during the winter months and the crystal moisture traps are the only option for you, they are good and can help to keep on top of any damp and mildew especially if you make visits and can change them when required.

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