Buying Guide
How to Buy a Dehumidifier
This short guide helps you choose the right dehumidifier for rooms, basements and laundry. It covers the key buying factors, the main types, the specifications to check, where to buy and common pitfalls so you can decide quickly and confidently.
Key factors to consider
Match capacity to room size and use. Look at extraction rate in litres per day rather than marketing claims. A 12 litre a day unit suits medium rooms and laundry use; 20 litre plus is better for large open-plan spaces or garages.
- Room size and damp level: measure the problematic room and note visible mould or persistent condensation.
- Extraction rate: 6, 12, 20 L/day are common tiers to compare.
- Operating temperature: choose a unit rated to work at low temperatures if you will use it in a cold basement or garage.
- Energy use: check running cost estimates. Modern compressor units can run from around 5p to 7p per hour depending on price of electricity.
- Noise level: bedroom models should be quieter, typically 36 to 42 dB for low-noise designs.
- Water management: tank size, auto shut-off when full, and whether a continuous drain hose is supplied.
- Portability and weight: look for castors and handles if you plan to move the unit between rooms.
Types and important specifications
Know the main types and the specs that matter for performance and convenience.
- Compressor dehumidifiers: most efficient for home use and laundry drying at typical indoor temperatures.
- Desiccant dehumidifiers: better at very low temperatures but often more costly and less energy efficient for everyday use.
- Mini absorbers: small, passive options for tiny cupboards or wardrobes but not suitable for damp rooms.
- Key specs to check: extraction rate (L/day), tank capacity (2 to 3 litres common), continuous drain option, adjustable humidity range (eg 30 to 80 or 90%), auto defrost for cold environments, built-in humidity sensor and digital display, timer and dedicated laundry dry mode.
- Other useful features: washable dust filter, child lock, full-tank alert, easy-empty handle and warranty length.
Where to buy and mistakes to avoid
Decide between online and in-store based on how much hands-on checking you want. Online gives wider choice and deals; retail lets you hear noise levels and check build quality. Always confirm delivery, returns policy and warranty registration.
- Buy online when you want variety, price comparison and home delivery; check customer reviews and Q&A for real-world noise and reliability reports.
- Buy in store if you need to test noise or judge build quality before buying.
- Check whether free shipping or quick returns are offered and whether an extended warranty is available.
- Buying a unit that is too small for the room.
- Ignoring the drain option and then needing to empty a small tank constantly.
- Overlooking operating temperature limits and buying a unit that will struggle in a cold cellar.
- Choosing solely on price and ignoring running cost and noise.
- Failing to check dimensions, weight and how easy the unit is to move or store.
Expert tips and quick checklist
Practical tips to get the most from your purchase and to use the dehumidifier efficiently.
- Measure the room and step up one capacity tier if damp is severe.
- Prefer units with a continuous drain hose for long unattended runs, such as in basements or for laundry drying.
- Choose a model with an accurate humidity sensor and set target humidity to around 45 to 55 percent for comfort and mould prevention.
- For bedrooms pick a quieter model or use sleep mode at night.
- Compare running cost estimates not just purchase price; energy efficiency saves money over time.
- Place the unit away from walls and obstructions so airflow is not restricted.
- Register the product for warranty and keep the receipt; check for at least a year of cover and options to extend.
Final Thoughts
Choose capacity first, then confirm features that suit your situation: continuous drain and auto shut-off for unattended use, low-noise options for bedrooms, and a sensible energy rating for everyday operation. If unsure, a 12 litre compressor dehumidifier with a 2 litre tank, continuous drain option and humidity sensor is a versatile starting point for most homes.
