A MERV rating is used to rate the ability of home furnace filters to remove airborne particles from the air as it passes through the filter. It is a standard used to measure the overall efficiency of a furnace filter and measures a filter's ability to remove particles from .30 to 10 microns in size. To give you an idea of the size of a micron, 100 microns is about the thickness of a piece of paper or a human hair.
The higher MERV rating the better performing a furnace filter us at the cleaning dirt, dust and grime particles from your air. The MERV rating needed for your furnace system comes down to your sensitivity to dust and other pollutants and air quality issues you face in your home.
A quality 8 MERV furnace filter will handle many of the larger air-borne particles that are common in most homes. However, if you or a loved one has respiratory issues it may be better to go with a 13 MERV filter. It is all based on personal preference and the conditions you face.
Here ere are examples of MERV ratings and the particles they filter:
- A MERV rating of 13 means the filter is 89-90% minimum efficient at capturing measured particles such as bacteria, tobacco smoke and particles that make you sneeze.
- A MERV rating of 11 means the filter is 80-85% minimum efficient at capturing measured particles such as humidifier dust, lead dust, milled flour, auto emissions and other fumes.
- A MERV rating of 8 means the filter is 60% minimum efficient at capturing measured particles such as mold spores, hair spray, fabric protector, dusting aids, cement dust and pet dander.
- Typical fiberglass throw-away filters are rated at a 4 MERV and below with a 6% minimum efficient at capturing the measured particles like pollen, sanding dust and large dust particles.
At PowerBrush Air Duct Cleaning we suggest a filter with a MERV rating of 8 or higher because your family's health is of critical importance. Avoid the cheap $2 fiberglass furnace filters found in the big box stores. They only capture large particles and allow respiratory irritants to continue circulating through your home.
Electrostatic Furnace Filters
Electrostatic furnace filters are becoming very popular with home owners who want to achieve better air quality in their homes. These air filters are designed to replace any type of panel filter or frame type air filter you currently use in your heating and air conditioning equipment. To keep your electronic or electrostatic air filters performing at maximum efficiency requires frequent and regular cleaning. Filter maintenance (changing or cleaning) also helps to keep your heating and cooling equipment operating at maximum efficiency which reduces operating costs.
Electronic Media Air Filters
When it comes to efficiency and cost these are probably among the most available to home owners. The big advantage of these filters over electrostatic air filters is they do not have to be rinsed clean every few months, just change the filter pad and reinstall the frame with a new pad.
Pleated Air Filters
Pleated Air Filters are among the most commonly used filters in residential and commercial applications. These filters are satisfactory for the average home that only requires moderate air filtration. HVAC pleated air filters are not the best choice for individuals who suffer from allergies and require very clean air. Although one inch is the most common thickness, two, four and even six inch thick filters are available. HVAC pleated air filters that are thicker than one inch can remain in use for longer periods of time before it is necessary to replace them. A pleated air filter, four or six inches thick can potentially remain in use for six months or more (depending on air quality conditions).
The material used to form the pleats is made of different materials. Some manufacturers use material that requires a wire mesh backing which helps to keep the filter material rigid and some manufacturers use material that is rigid enough to keep its shape without extra support.
A disposable or reusable filter that is left in an air conditioning or heating system for extended periods of time without proper maintenance can reduce airflow to the point of causing costly equipment breakdowns.
HEPA Air Filters
HEPA air filters are commonly used in environments where very clean air is a must, such as clean rooms, hospital wards, surgical rooms and other places where maximum dust removal is very important. HEPA filters are also used in many other applications such as very efficient HEPA vacuum cleaners and HEPA air cleaners.
Activated Carbon Air Filters
Installing a carbon air filter in your furnace or air conditioning system is very effective at removing pet, smoke, garbage and mold odors. This reduces the need for unnatural solutions to odor problems and there is no need for chemicals or sprays which can cause allergic reactions.
Some of these filters such as throw away fiberglass filters are not very efficient and will only trap the largest of dust particles, while others such as the electrostatic filter and HEPA air filter will remove over 97 percent of household allergens from the air that passes through them.