Motorhome Windscreen Condensation 6 Comments


How to get rid of that annoying condensation.

When it’s cold and wet outside, the windscreen in the morning gets absolutely wet through on the inside. Warm air in the van condenses on the cold glass and creates lots of condensation. You heating creates it and so does your exhaled breath. There are a few options to help reduce this problem all with varying results and costs:-


  1. Opening a window.

    • Pros
      • Costs nothing.
      • No storage requirements.
      • Quite effective at reducing the condensation.
    • Cons
      • Lets the warm air out and cold air in.
      • Remember to close the window before driving off.
      • Does not eliminate the problem.
  2. Just use a cloth.

    • Pros
      • Cheap and easy.
      • Storage not an issue
    • Cons
      • Not very effective and leaves lots of residual water.
  3. Buy a windscreen cover for the outside of your vehicle.

    • Pros
      • They have the advantage of keeping the inside of the vehicle warmer by keeping cold air off the glass.
      • Very effective against condensation with little or no residual water.
    • Cons
      • They are can be expensive to buy (they can be over £350).
      • High storage space requirements.
      • Can be a hassle to install.
      • Might not eliminate the problem.
  4. Window Vacuum.

    • Pros
      • No too expensive. (under £70)
      • Small storage requirements.
      • Removes all the water from the glass.
      • Can also be used at home.
    • Cons
      • Not the cheapest option on the market.
      • Needs recharging every so often.
      • Better than using a cloth.

We considered the pros and cons of each and opted for the window vacuum, there are a few on the market but we opted for a reputable brand and bought a Karcher WV2 window vac. It works brilliantly for getting the water and condensation off, whether its the windscreen or a conservatory back home. The battery life provides many days of use and charges up in 1-2 hours depending on how flat the battery gets. Sadly the unit requires 240v electricity but we have an inverter so it’s not a problem. However……

I had a look at the electrical output of the charger and guess what? 5v at 600mA. If it had a different connector on it could be charged up via a USB socket, so now I need a spare charger for it so I can cut the charger off and fit a USB plug instead, i can then plug it into a cig lighter adapter or computer to charge it up then instead of having to use the 240v inverter. If you have any thoughts please feel free to share.

Well it looks like Alistair (in the comments section) tried the DIY USB wire idea and it works perfectly and kindly offered to make us one too.


Verdict: Well the Karcher WV2 window vac is a good compromise that works perfectly for us and would definitely recommend it.


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6 thoughts on “Motorhome Windscreen Condensation

  • Paul Hillman

    I have just come across your blog and I am really enjoying the read I would like to ask if you found a usb charger for your Karcher we are hoping to do similar to what you are doing next year and I am getting loads of ideas from you experience.

    • Bumble Crew Post author

      Hi Paul, i never got around to it, it should just be a case of putting a USB plug on the end of the lead instead of the charger, it was all a bit rush, rush as we left, it soon charges on the inverter though, we just charge it whilst driving usually. If you get round to trying it let us know.

  • Gary Davies

    I saw a tip that suggested putting cat litter (which is designed to absorb moisture) inside an old sock. Not tried it myself.

    • Bumble Crew Post author

      Hi Gary, I think the problem with it though is how much can it actually absorb, it’s the same as the shop bought small dehumidifiers they sell I suppose but I don’t think it would be that effective to be honest, leaving a window or skylight open a little helps a lot as it lets the moist air out, but sadly the warm air goes with it. If you have some kitty litter then give it a go and let us know how well it actually works, we’d love to know if such a simple system could be effective and I’m sure other people would too.

  • Alistair

    The wire is very easy to make, £4.99 replacement plug eBay/amazon & £0.78 for a diy USB plug two drops of solder, job done & it works !

    I bought 10 USB plugs, seamed a shame to just post one, so if you want one let me have your address .. the least I can do for all the wonderful information !