How indoor air quality affects your health

Indoor air quality is a big part of staying healthy. According to the heating and air conditioning engineers at ASHRAE*, most people spend 90% of their time inside their home.  
Heating, ventilation and cooling (HVAC) systems provide comfortable temperature and humidity levels. Humid indoor air contributes to an increase in mold spores and dust mites. On the opposite end of the scale, extremely dry air can contribute to upper respiratory infections and skin conditions like eczema.

How to improve indoor air quality 

Furnace filters capture particles that contribute to allergies, asthma and illnesses
  • Dust
  • Pollen
  • Mold
  • Bacteria
  • Pet dander
  • Cooking oil smoke
  • Viruses
  • Tobacco smoke
  • Smog

How long does a furnace filter last?

Furnace filters last 1-3 months.
Some furnace filters are more effective than others. A Minimum Efficiency Reporting Value (MERV*) designates a filter’s effectiveness.
The three most common residential furnace filter ratings are:
MERV 8: Good
MERV 11: Better
MERV 13: Best
A MERV 8 filter removes fine particles from the air. MERV 11 and 13 filters capture even finer particles. As the table below shows, your specific circumstances help determine what quality furnace filter to buy. And the quality you choose determines how often it should be replaced
If you live in an older home or a city with dirtier air, the highest quality furnace filter will help protect you from adverse health effects. If you live in a brand new home in a small town with cleaner air, a MERV 8 or 11 might be just fine. Similarly, it might be more important for people with allergies or asthma to use higher quality filters
The bottom line: You should replace low quality filters, sometimes labeled 30-day filters, every month. Higher quality filters should last 2-3 months. Follow the manufacturer’s recommendations or ask your HVAC contractor.

How much do furnace filters cost? 

Furnace filter cost varies by quality rating and quantity of filters purchased. Of course, you always get what you pay for. High quality filters extend your HVAC system’s life and capture smaller particles, like viruses and tobacco smoke.
Changing the filter regularly is an important part of maintaining your heating and air conditioning system. But, even if you remember the size and MERV rating for your furnace, shopping for a filter is not at the top of most people’s To Do list

Buy furnace filters online

Never worry about remembering to buy or change your furnace filter again. Buy American made filters, factory direct from Filter Fetch.  Filter Fetch delivers professional grade filters right to your door with free shipping.
Your heating and cooling contractor can recommend the best filter for your equipment, region and household. Or use the handy Filter Fetch ordering tool. Choose the quality that best meets your family’s needs. Then set up a recurring shipment of a year’s worth of filters at a discount. What could be easier?
*ASHRAE, a society for heating, refrigerating and air-conditioning engineers, established MERV ratings in 1979.

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What Furnace Filter Should I Buy?


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