Have you checked the condition of your air filter? Often, people forget to check their air filters and just leave it there for a very long time, years even. This is bad because commercial air filters are only designed to be used for three months and would require replacing afterwards. After three months, filters are not so effective anymore because the dust particles clog the small holes where the air passes through the air filter which results to your heater or air conditioner not only blowing weak air but blowing dirty air as well. The dirty air that gets through a dirty filter is pretty nasty because it carries things like dust mites which causes allergies, molds which can cause lung infections and even airborne viruses that can cause very deadly illnesses like SARS.
The best way to avoid allergies and sicknesses from airborne disease carriers at home is to always clean and always ensure that your air filters are clean. When it comes to your A/C or furnace air filer, you should ensure safety by frequent replacement and by choosing only the best equipment available like 3M’s Filtrete or maybe a Honeywell furnace filter. By getting these trusted high quality brands, you ensure that as long as they are within their recommended life span, they will give you maximum protection from floating particle pollutants and viruses. Some of these high quality filters are even electrostatically charged in order to draw in harmful viruses and particles.