Buying Guide
Best Portable Dehumidifiers for Caravans & Boats UK 2026
Updated June 2026
Caravans, motorhomes and narrowboats have a unique damp problem. They are small, unheated for weeks at a time, and temperatures drop near freezing in winter. Standard compressor dehumidifiers stop working below 15°C — which means they are useless in an unheated caravan from October to March. You need either a desiccant dehumidifier (works at any temperature) or a moisture absorber (no electricity needed). Here are the best options.
Quick answer
For caravans stored over winter: UniBond AERO 360 moisture absorber (no electricity, silent, £10). For caravans you visit regularly: EcoAir DD1 Classic desiccant dehumidifier (works down to 1°C, lightweight at 6kg, £130–£170).
Why caravans and boats get so damp
Caravans, motorhomes and narrowboats are sealed, single-skin boxes with almost no insulation. When outdoor temperatures swing from 2°C overnight to 12°C by midday, moisture in the air condenses on every cold surface — windows, walls, lockers, and inside cushions. Unlike a house, there's no central heating drying things back out.
Soft furnishings make it worse. Mattresses, cushions and curtains soak up moisture and become a perfect mould substrate. Narrowboats face an extra problem: they sit on cold water, which keeps the hull and floor below dew point for most of winter.
The result is predictable. Most UK caravan owners return in spring to find black mould on cushions, curtains, mattresses and around the window seals — even though the caravan looked clean and dry when they locked it up in October.
Desiccant vs compressor vs moisture absorber
Compressor
Useless below 15°C. Not recommended for unheated caravans. Only an option if you have hookup and keep the heating on.
Desiccant
Works at any temperature, lightweight, ideal for caravans and narrowboats — but needs electric hookup or shore power to run.
Moisture absorber
No electricity, silent, perfect for stored caravans. Slower than a dehumidifier but the only realistic option when there's no power.
For a deeper comparison see our desiccant vs compressor dehumidifier guide.
The top 5 products for caravans and boats
UniBond AERO 360° Moisture Absorber
£8–£12
No electricity, no noise, no maintenance. Leave it in your caravan all winter and it silently absorbs moisture from the air. Replace the tab every 1–3 months depending on damp levels.
- No electricity needed
- Completely silent
- Lasts 1–3 months per tab
- Perfect for stored caravans
EcoAir DD1 Classic MK6
£130–£170
Works down to 1°C — perfect for unheated caravans and narrowboats in winter. At just 6kg, it's the lightest full-size dehumidifier on the market, easy to carry in and out on visits.
- Works at any temperature
- Only 6kg — easy to carry
- 7L/day extraction
- Quiet enough for sleeping
Devola 12L Low Energy
£85–£110
If your caravan has electric hookup and stays above 10°C, this compressor model costs less than 5p per hour and handles the moisture easily.
- Under 5p/hour to run
- 12L/day extraction
- Continuous drain option
- 2-year warranty
Thlevel Mini Hygrometer 4-Pack
£7–£10 for 4
Leave one in each room of your caravan. Check readings when you arrive — if above 70%, you have a problem and need to act before mould appears.
- 4 units for under £10
- Battery powered
- Tiny — fits anywhere
- No setup needed
Dryzone Mould Remover & Prevention Kit
£15–£20
Spring clean your caravan with this dual-action kit — removes existing mould and applies a long-lasting protective coating to prevent regrowth.
- Removes and prevents
- Safe on soft furnishings
- Long-lasting protection
- No bleach smell
Caravan winter storage checklist
- 1
Clean all surfaces with mould prevention spray before locking up
- 2
Place moisture absorbers in each room or compartment
- 3
Leave a hygrometer in each area so you can check readings on visits
- 4
Crack a roof vent or window slightly for airflow (security-locked)
- 5
Remove all soft furnishings if you can — cushions, mattresses, bedding
- 6
Check and empty moisture absorbers monthly through winter