Does a Dehumidifier Bring in Fresh Air?

Ordinary Household Dehumidifier Working Principle

A portable home dehumidifier does not bring in fresh air from outside. Ordinary household dehumidifiers on the market do not introduce outdoor fresh air. They achieve indoor air circulation, inhaling humid indoor air, processing excess moisture through their evaporator and condenser, and releasing air that meets the rated humidity.

It pulls in air from the room, removes moisture from it using a cooling coil (like how a cold soda collects condensation), and then releases the drier air back into the same space. It does not ventilate the space or provide any air exchange with the outdoors. Suppose you're looking to bring in fresh air. In that case, you’d need something like a ventilation system (like an HRV or ERV), an open window or exhaust fan, or an air purifier with an intake function, though most purifiers also just circulate indoor air. However, the most effective way is to use a dehumidifier with fresh air intake.

 

Preair Whole House Dehumidifier for HVAC System

A whole-house dehumidifier with fresh air intake is a great option if you're looking to both control humidity and introduce fresh outdoor air into your home in a controlled and energy-efficient way.

How Does a Whole House Fresh Air Dehumidifier Work

Dehumidifies indoor air — like a regular dehumidifier.

Pulls in outdoor air — using a dedicated fresh air intake duct.

Mixes and conditions that outdoor air with indoor air (filters, sometimes temp-adjusts).

Distributes it throughout the house via your HVAC system or dedicated ductwork.

Key Features of a Whole House Dehumidifier

Fresh air intake damper or control – lets you adjust how much outdoor air comes in.

MERV-rated filters – to clean incoming air (especially important if you’re pulling air from a pollen-heavy or polluted area).

Compatibility with HVAC – some units integrate directly with your furnace or AC.

Energy recovery ventilation (ERV/HRV) – some higher-end models recover heat/cool from the incoming/outgoing air to maintain efficiency.

Common HVAC Dehumidifier Models

Preair WH70 - capacity of 70 PPD, MERV8 filter, support for HVAC system.

Preair WH95 - 95 PPD, MERV8 filter, outstanding quality.

Preair WH135 - 135 PPD, MERV8 filter, known for fresh air function.

PREAIR is a reliable dehumidifier manufacturer that develops various types of dehumidifiers for sale. Whole-house dehumidifiers have a profound market. More and more apartment and business buildings need a fresh air system.

 

Based on your house size, climate, or any allergies/air quality concerns, Preair company will provide you with professional suggestions. Please feel free to contact us.