Dehumidifiers: a guide to choosing the best one (Portugal)

Dehumidifiers: a guide to choosing the best one (Portugal)

A dehumidifier removes excess moisture from the air, helping to reduce condensation , mold/mildew , "damp house" smells, and dry clothes indoors. The goal is not to make the air "too dry," but to maintain the relative humidity within a comfortable and healthy range—ideally between 30% and 50% and below 60% .

1) Signs that you need a dehumidifier

  • Small droplets on the glass/windows (frequent condensation)

  • black/gray stains on the walls (mold)

  • persistent musty smell

  • Clothes taking too long to dry indoors.

  • “Cold and damp” room (storage, basement, laundry room)

Tip: If the cause is lack of ventilation, a dehumidifier can help, but proper ventilation is still important.

2) Rule #1: Choose based on extraction capacity (liters/day)

The capacity indicates how many liters of water the device can remove in 24 hours under specific conditions (usually "favorable" conditions, so it may vary in everyday use).

Practical reference (DECO):

  • < 16 L/day → recommended for rooms 20–25 m² (indicative values)

  • 16–21 L/day → recommended for 35–40 m² (indicative values)

✅ To decide quickly:

  • Small bedroom/office → typically <16 L/day

  • Large room / multiple sources of humidity → 16–21 L / day

3) Compressor vs. Desiccant: Which technology is better in Portugal?

There are two main types:

A) Compressor dehumidifier

  • It tends to be more efficient in warmer environments.

  • It may lose effectiveness in cold rooms (e.g., poorly heated houses in winter).

B) Desiccant dehumidifier (desiccant)

  • It works more consistently in colder environments.

  • It tends to warm the air slightly , which can help with drying clothes.

✅ Shortcut choice:

  • Cold laundry room / garage / unheated room → desiccant

  • Room/bedrooms with "normal" temperature → compressor (often better cost/efficiency)

4) Hygrostat and automatic modes: a "must-have" for saving energy.

Looking for a model with:

  • hygrostat (defines a target humidity level, e.g., 50–55%)

  • Automatic mode (turns on/off according to humidity)

This prevents over-dehumidification (very dry air) and helps maintain humidity within a recommended range.

5) Tank vs. continuous drain: everyday comfort

Points to compare:

  • Tank size (the larger the tank, the fewer trips needed to empty it)

  • Continuous drain (connection to sewer) — ideal for extended use.

✅ If you have a lot of humidity or want to dry clothes frequently, continuous drain is a real upgrade.

6) Dry clothes with a dehumidifier (no smell and no "towel bath")

For many people in Portugal, the dehumidifier is the "plan B" in winter and on humid days:

  • Close the room, hang the laundry leaving space between items.

  • Use the "Laundry"/drying mode (if available).

  • A desiccant tends to dry faster in cold rooms because it also heats the air.

7) Energy consumption and "energy label"

Here's an important detail: there is no specific EU energy label for dehumidifiers (they are not covered by energy labeling regulations like some other products).

✅ So how do you compare consumption?

  • checks power (W) and, above all, behavior in automatic mode (hygrostat)

  • Read tests/measurements and look for models that shut down when they reach the target humidity level.

8) Essential maintenance (to maintain effectiveness and prevent odors)

  • Clean the filter regularly (if there is one).

  • Empty and wash the tank (prevents odors)

  • Ensures space around the appliance for good air circulation.

  • confirms the minimum operating temperature (especially in cold rooms)

FAQ

What is the ideal humidity level inside a house?
In general, it is recommended to maintain humidity levels between 30–50% and below 60% for comfort and to control humidity problems.

How much dehumidifier capacity do I need for 20–25 m²?
DECO indicates that models with a daily extraction rate of less than 16 L/day are recommended (indicative values).

Does a dehumidifier help dry clothes?
Yes, especially in humid rooms. Desiccant models tend to be faster in cold environments because they also heat the air.

Is there an EU energy label for dehumidifiers?
The European Commission indicates that dehumidifiers are not covered by EU energy labeling regulations.