Guide

Dehumidifiers --
the comprehensive guide

Which dehumidifier is the right one? Everything you need to know about device types, areas of application, selection criteria, and professional operation -- compactly summarized by the DÖLCO experts.

To Room Drying →Expert Consultation: +49 7664 50559-0

Basics

How does a dehumidifier work?

Dehumidifiers remove excess moisture from the ambient air, thereby helping to drop below the dew point. This prevents condensation on cold surfaces and inhibits mold growth.

The most common type -- the condensation dryer -- cools the moist room air below the dew point; the resulting condensate is collected or drained via a hose. The adsorption dryer, on the other hand, uses chemical binding forces and works reliably even at very low temperatures.

For professional damage restoration, only high-performance devices according to the DÖLCO standard are used, which are significantly more powerful than standard household appliances.

Technical terms explained

Relative humidity
Ratio of the existing to the maximum possible amount of water vapor at a specific temperature (in %).
Dew point
Temperature at which the existing air humidity turns into condensation -- critical on cold exterior walls.
Dehumidification capacity
Amount of water removed per day (l/d) -- the most important performance feature of a dehumidifier.
Water-energy quotient
Ratio of dehumidification capacity to energy consumption (l/kWh) -- a measure of efficiency.

Device types

Dehumidifier types
at a glance

Not every device is suitable for every application. Here you will find the most important device types and their specific strengths.

01
Condensation dehumidifier
The most common principle: Warm, moist air is cooled via a refrigerant heat exchanger, and the condensate is collected. Efficient at temperatures above 15 °C.
02
Adsorption dehumidifier
Moisture is bound from the air by a hygroscopic sorption agent (e.g., silica gel). Excellent performance even at low temperatures down to -20 °C.
03
Insulation layer dryer
Developed specifically for drying under screeds. Dried air is fed directly into the cavity via drill holes and hoses.
04
Large-scale dehumidifier
High-performance devices for construction sites, halls, and commercial properties. Dehumidification capacities from 100 to over 400 liters per day.
05
Construction dryer
Robust devices for use on construction sites. Protected against dust and damage, stackable, and with a large condensate tank.
06
Residential dehumidifier
Compact, quiet devices for continuous use in living rooms, basements, and archives. Continuous operation with automatic shut-off.

Areas of application

Where are dehumidifiers
used professionally?

🏗️
New construction & building drying
Construction moisture from concrete, screed, and masonry must be completely removed before occupancy. Dehumidifiers significantly shorten the drying time.
💧
Water damage restoration
Core task: After pipe bursts and flooding, the component moisture is reduced to the target level using high-performance devices.
🏠
Basements & crawl spaces
Permanently increased air humidity in basements promotes mold and material damage. Continuous-operation dehumidifiers provide a remedy.
📦
Warehouses & archives
Paper, wood, and electronics are sensitive to moisture. Precise humidity regulation protects valuable goods.
🏊
Indoor pools & spas
High evaporation rates require powerful dehumidification solutions to protect the building structure.
❄️
Winter construction heating
In winter, combined heating and dehumidification devices ensure concrete-compatible temperatures and controlled air humidity.

Buying advice

How to choose the right
dehumidifier

Six criteria that are decisive when selecting a device.

01
Room size (m²)
Larger rooms require higher dehumidification capacity. A rule of thumb is: 1 liter per day per 10 m² for normal conditions.
02
Temperature
Below 15 °C, condensation dehumidifiers lose significant performance. For winter use, adsorption dryers are the right choice.
03
Initial humidity
With very high component moisture (> 95% rel.), high-performance devices are necessary. The CM measuring device indicates the exact moisture content.
04
Operating time
Continuous operation requires an automatic condensate drain. For short-term use, a generous collection tank is sufficient.
05
Noise level
For use in occupied buildings, devices with a low sound pressure level (< 45 dB(A)) should be selected.
06
Energy efficiency
Modern DÖLCO devices have a water-energy quotient of up to 3.0 l/kWh -- significantly better than older models.

Professional consultation

Questions about the right device?

Our expert consultants will help you with device selection and optimal sizing for your specific application -- free of charge and without obligation.

+49 7664 50559-0 →Submit online inquiry
📞 +49 7664 / 50559-0☎ 0800 50559 00 (free of charge)✉ info@doelco.de