Dehumidifier Buying Guide: 30L vs 50L vs 70L Capacity

Understanding Dehumidifier Capacity Ratings

Dehumidifier capacity (measured in litres per day) indicates how much moisture the unit can extract in 24 hours under standard test conditions (30C, 80% RH). Choosing the right capacity ensures efficient operation without excessive cycling.

Quick Size Guide

30L/Day Dehumidifiers

30L/day dehumidifiers are the sweet spot for residential use. They're compact enough for apartments and bedrooms while still powerful enough to handle damp-prone areas like bathrooms and kitchens.

Key Features to Look For

• Hygrostat (humidity thermostat) - sets target humidity and auto-shuts off
• Continuous drainage option - no tank to empty
• Washable air filter - protects the compressor
• Auto-defrost - works in cooler rooms (5C+)
• LED display - shows current humidity

50L/Day Dehumidifiers

50L/day dehumidifiers bridge the gap between residential and commercial use. They're ideal for basements, large living areas, and small commercial spaces.

Best Applications

• Basements prone to damp and mould
• Large open-plan living areas
• Small warehouses and storage rooms
• Laundry drying rooms
• Basement and server room protection

70L/Day Dehumidifiers

70L/day dehumidifiers are heavy-duty units designed for industrial and commercial environments. They feature powerful compressors and larger fans for high-volume air processing.

Best Applications

• Warehouses and storage facilities
• Server rooms and data centres
• Workshops and factories
• Flood recovery and water damage restoration
• Indoor swimming pool areas

Key Features Comparison

How to Calculate Your Dehumidifier Needs

Beyond room size, consider these factors:

1. Current humidity level: Use a hygrometer to measure. Above 60% RH needs a dehumidifier.
2. Moisture sources: Bathrooms, kitchens, and drying laundry add significant moisture.
3. Ambient temperature: Compressor dehumidifiers work best above 15C. Below that, consider desiccant types.
4. Insulation and ventilation: Poorly insulated rooms need more capacity.

Energy Efficiency Tips

• Set the hygrostat to 50-55% RH - lower settings waste energy
• Use continuous drainage instead of the tank to ensure uninterrupted operation
• Close doors and windows while dehumidifying
• Clean the air filter monthly
• Position the dehumidifier centrally with clear airflow around it

Frequently Asked Questions

Can a dehumidifier be too powerful for a room?

While overcapacity isn't harmful, it's unnecessary spending. However, for damp basements, choosing one size up ensures faster moisture removal and fewer running hours.

How much does it cost to run a dehumidifier?

A 30L dehumidifier at 350W costs approximately €0.04/hour to run. At 8 hours/day, that's about €10/month. A 70L model at 900W costs about €0.10/hour.

Can I use a dehumidifier and heater together?

Yes! Dry air feels warmer at the same temperature, so dehumidifying can make a room feel 1-2 degrees warmer. This means you can lower your thermostat and save on heating costs. Browse our electric heaters to pair with your dehumidifier.

Shop All Dehumidifiers

• All Dehumidifiers
• 30L/Day Dehumidifiers
• 50L/Day Dehumidifiers
• 70L/Day Dehumidifiers
• Basement & Server Room Dehumidifiers

All DAHTEC dehumidifiers include a 3-year warranty and free shipping across 22 European countries. Questions? Contact us for expert advice.