As more people seem to develop severe allergies and respiratory problems, attention has shifted to high-efficiency air filters as a solution. For the price are they worth it?
If you don’t sit by one at work or have one in your family, you probably are one: that unfortunate person who greets each spring and fall with a bright red nose, watery eyes and the ever-present box of tissues.
Filtering out the allergens
With so many people suffering from allergies and respiratory issues, it’s no wonder that attention has focused on HVAC (Heating, Ventilation and Air Conditioning) system air filters. Manufacturers are working to create more effective filters while trying to maintain HVAC system efficiency.
The clash is this: as you create a material that filters out smaller and smaller particles, those materials also block more of the air flow. After all, the ultimate material for filtering pollutants would be a non-permeable sheet of plastic, right? Wrong. No air would get through the plastic, causing the fan system to blow progressively harder until it burned out. Plastic is an efficient pollutant blocker, but inefficient for air circulation.
Better filtering or energy-efficiency?
So if you purchase higher-quality air filters, are you actually blocking air flow and making your HVAC system work even harder? Yes. You’re not only buying more expensive air filters, but you’re also using more energy – higher costs all around. The challenge becomes to find a material that filters out the small particles while allowing sufficient air flow.
Currently, HVAC air filters are made of paper, fibreglass or other synthetic materials. They come in filtering efficiencies of:
- 60-80% Minimum Efficiency Reporting Value (MERV)
- 80-95% MERV (usually good enough for homes, barring allergies)
- Greater than 95% MERV
- Greater than 98% MERV
Obviously the higher the MERV rating, the more dust, mould spores, bacteria, pollen and other detritus that gets trapped. Consequently, the lower the air flow and the harder your system must work. A quick and easy way to test your own filter's effectiveness is to pour table salt into it. If any falls through, the filter isn’t doing much.
Superior new options
Luckily, today we have premium air filters on the market that hold more pollutants, so they don’t have to be changed as often. While they do cost more, these premium filters result in enough energy savings to be worth the extra price. In fact, they are said to pay for themselves within three years due to extra energy efficiency. Also, they need to be changed/disposed less often, which means they’re also environmentally friendlier.
To learn more about whether your HVAC air filters are working efficiently and effectively for your space, talk to an HVAC technician today.
