Do SafeHome Filters cause too much air resistance?

Air resistance problems can occur with any filter. Click on the question to learn about this common problem, how to prevent it, and for air flow specifications of SafeHome Filters.

Background on Air Resistance

Adequate air flow is critical for air conditioning systems to function properly. Several factors affect the flow of air through your system (filter size and type, the system fan, overall system design, etc.), but the greatest factor in air flow reduction is filter size. The larger the filter, the better the air flow because larger filters allow the same amount of air to pass through more slowly. Your air filter size was determined by the HVAC contractor who designed your air system.

Too much air resistance can drive up your energy costs and cause a major strain on your air system, which can lead to a temporary or permanent shut down. However, when properly sized, almost any high quality filter can be used without causing too much air resistance.

Safehome Specifications and Analysis

(Air Resistance is measured in units called “water gauge” or WG)

Air resistance measurements at 300 feet per minute:

SafeHome System – 0.13 WG

SafeHome Duo – 0.14 WG

This is significantly lower than many filters now on the market with resistance as high as 0.25 WG at 300 fpm, but it is higher than the average filter available on store shelves at up to 0.10 WG. In a properly designed HVAC system, even 0.20 WG should not present a significant problem.

Unfortunately, problems with air resistance are usually caused because the system was designed with too small of a filter. When this is the case, only filters with extremely low air resistance can be used – the cheap, blue fiberglass filters – which do nothing for indoor air quality.

How to prevent an air resistance problem:

1)    Make sure you change your filter regularly. Many households can get away with changing their filters every 3 months, but those with pets or a high amount of dust should change their filter every 1-2 months. Even the cheapest blue filter can cause a strain on your system if it is clogged with dust and pet hair. This is one of those home maintenance tasks that is hard to remember! All of our filters come with stick-on labels that will help you remember when to change your filter.

2)    If you purchased a SafeHome System, only use the allergen filters supplied. If you need to change the allergen pre-filter more often, you can purchase extras here .

3)    Pay attention to your air system. If it is not heating or cooling your house properly, or if the fan is running continuously even on “auto” mode, you may need to have your system checked by a licensed HVAC service provider.

4)    When building a new home or replacing your air system, be sure that your HVAC contractor considers filter size when designing your system. Express to them that indoor air quality is a priority and that you plan to use a high quality air filter that has the above air resistance measurements.