Today, many families are beginning to pay attention to indoor air quality, and both fresh air systems and air purifiers are devices designed to improve indoor air quality. However, for those who already have a fresh air system installed, is an air purifier still necessary?

The answer is: Yes, but not necessarily.

First, let us understand the functions and principles of these two devices.

A fresh air system is designed to maintain indoor airflow by introducing fresh air and exhausting stale indoor air. It brings outdoor air inside through ducts or specialized equipment, thereby increasing oxygen levels and discharging pollutants and carbon dioxide. This helps keep the indoor air fresh and reduces the accumulation of odors and contaminants.

An air purifier, on the other hand, purifies air by filtering out particles and pollutants already present in the room. They utilize different types of filtration technologies, such as HEPA filters, activated carbon filters, or ionizers, to remove airborne pollutants like dust, pollen, bacteria, viruses, and volatile organic compounds (VOCs).

Reasons why you might still need an air purifier even with a fresh air system

1. Sources of indoor air pollutants

There are several main sources of indoor air pollution:

● Outdoor air: Pollutants from the outdoors (such as dust, PM2.5, ozone, etc.) can enter the home through open windows or ventilation.

● Interior decoration: Pollutants generated during the renovation process (such as formaldehyde, VOCs, etc.) can remain in the indoor air, posing a threat to human health.

● Household items: Formaldehyde and VOCs from household products can also be released into the indoor air.

● Human activity: Daily activities produce carbon dioxide, formaldehyde, and other pollutants.

A fresh air system is primarily used to improve ventilation and air freshness; it can effectively reduce PM2.5 concentrations but has limited effectiveness in removing pollutants like formaldehyde and VOCs. Therefore, if these specific pollutants are present, an air purifier is needed for further purification.

2. The supplementary role of the air purifier

While a fresh air system introduces fresh outdoor air, it may not completely remove all outdoor pollutants. Thus, if the outdoor air quality is poor, an air purifier can be used to purify the incoming air to ensure optimal indoor air quality.

Reasons why you might NOT need an air purifier with a fresh air system

1. Low concentration of indoor air pollutants

If the concentration of indoor air pollutants is already very low, you may consider not using an air purifier.

2. Indoor pollutants originate mainly from the outdoors

If indoor air pollutants are primarily entering from outside, you can reduce the concentration by limiting window ventilation, thereby decreasing the need for an air purifier.

In conclusion, whether an air purifier is still needed when a fresh air system is present depends on the specific circumstances. If formaldehyde, VOCs, and other chemical pollutants are present, an air purifier should be used for further purification. If overall air pollutant levels are consistently low, it may be omitted.