The best car dehumidifiers for idle cars and cars in storage

Curtail condensation and mould growth in your idle car with a car dehumidifier. We decide which are best.

Moisture on a car windscreen

by Chris Williams |

Mould is welcome in certain cheeses and breaks down organic matter in the garden. Beyond that, it has no place in our lives, and certainly not in our cars. But that's always going to be a battle. A battle you can win but it requires some attention. A car interior is a confined space in which we exhale moisture and transport wet dogs. Old cars also have the added issue of not being well sealed, meaning external moisture can penetrate the interior too.

When a modern car is in use, we have the air conditioning on to quell the build-up of moisture. But when we have the car sitting idle, or we are sitting idle in the car waiting for the takeaways to be ready, what then?

Dehumidifiers can step in. They're great because they absorb moisture from the air. When the air is dry, mould or mildew growth is inhibited and so too are the musty smells that come along with them. We've recommended a small selection of the best car dehumidifiers to use when a car is idle or in storage.

Related: The best car vacuum cleaners

The best car dehumidifiers

Hillington Reusable Car Dehumidifier Bags

Editor's pick
Hillington Reusable Car Dehumidifier Bags
Amazon

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Our top-rated car dehumidifiers are some silica-filled bags. It's the best option because these 1kg bags can absorb up to 400ml of water each. Therefore you can have them in a vehicle for a long time before 'recharging' and they can be used in large vehicles too, including campervans.

There are many silica-filled bags on the market but we rate these ones not only because the volume can soak up but also because they bear two handy features. One is the blue dot. When the bag has absorbed all it can, the dot goes blue. You then 'recharge' it (about once a month) and the dot goes pink. The second useful feature is the inclusion of non-slip pads that you can use to stop the bags from sliding off a dashboard, for example.

Bamboo Charcoal Bag (2 X 500g)

Best for air purifying too
Bamboo Charcoal Bag (2 X 500g)
Amazon

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Activated bamboo charcoal is fantastic for air purification and drying. The charcoal is porous, allowing moisture and odours to be absorbed. A pair of 500g bags is good for the car, but you can use them around the house too, if you wish. They are reusable, all you need to do is expose the bags to sunlight for a couple of hours each side at least once a month.

Gadlane Reusable Car Dehumidifier Bags

Best value
Gadlane Reusable Car Dehumidifier Bags
Amazon

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Gadlane's dehumidifier bags are the same size, filled with the same silica gel, and capable of absorbing the same volume of water as the Hillington bags. However, they don't come with the moisture indicator or non-slip pads. Nevertheless, they still do a brilliant job of absorbing moisture. To 'recharge', simply put them on a radiator, in the microwave, or just air them out.

Pingi ID-A300 Car Dehumidifier

Pingi ID-A300 Car Dehumidifier
Amazon

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The dehumidifier bags are your best option. But if you want a device, there are a couple of options, the best of which is this. This compact cordless dehumidifier can inhale 120 grams (i.e. 120ml) of water. You know when it's full because the oval goes from orange to green.

Being cordless, you'd imagine the ID-A300 is battery powered, but in fact, it's not the case. Just as the bags need to release collected moisture, so too does this and that is what plugging it in achieves. However, it needs to be plugged in for a long time - 15 to 20 hours - in order to release all the moisture.

Odour eliminators

Dehumidifiers dry the air and help avoid moisture-related problems in the first place. But of the dehumidifiers above, only the bamboo charcoal will purify the air and eliminate odours too. Meanwhile, air fresheners mask a smell but don't eliminate the cause. The cause could simply be an AWOL egg and mayo sandwich or rancid old socks that need to be removed from the car. But smells penetrate fabrics and need to be dealt to.

The best solution to permanently avoid smells permeating throughout a car interior is to keep the interior clean. To know exactly how to best clean your car's interior, read our guide. Air it out too on a nice day.

You can also use an odour eliminator spray such as the Parkers-recommended Autoglym Odour Eliminator below. It can be used on fabric and carpet, ridding them of smells left by food or cigarettes, for example. If there is mould, you can use white vinegar and water to get rid of it.

Related: The best car cleaning products

But the issue can lie in the air conditioning system because car air-con can also be subject to mould and bacteria growth. An air conditioning evaporator takes moisture from the air and it normally drains what it collects through a hose. But that tube can suffer from a blockage. This can result in moisture pooling in the evaporator, causing mould or mildew problems inside the air-con system.

To combat this, unblock the drain hose (it's a simple task and there are many YouTube videos showing you how) and use an air-con cleaner to kill the bacteria. We recommend STP Air-Con Cleaner. It's easy to use, just run the air con (doors shut and no one in the car) with the STP spray for 10 minutes before ventilating the car thoroughly.

Related: The best diesel engine cleaner

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