January 2010
Ready for a Change

Having a clean air filter is critical to efficiency

Can you remember the last time you changed or cleaned your heating system's air filter?

Not only does a clean filter trap more dirt and dust before it goes into your furnace; it also helps retain the efficiency of the entire system.

Look at it this way - a dirty filter is like trying to breath with your hand covering your mouth and nose. Your furnace has to work much harder than it should. That also means it uses more energy than necessary.

Change or Clean?

Whether you change or clean your air filter depends on its type. Styles range from cheap, disposable filters all the way to electronic air cleaners costing hundreds of dollars.

Just because your system was installed with one type of filter doesn't mean you're stuck with it. It's easy to upgrade if you want cleaner air. Call a licensed heating and air contractor to do the job.

These are the main type of filters available for home heating systems:

Disposable - use once and throw away when they become dirty. Their lifespan usually depends on the season. You'll have to change disposable filters more in the dead of winter than in the milder fall and spring seasons.

There are different grades of disposable filters available, ranging from the very cheap to fairly efficient models that last a few months. Disposables trap only the largest dirt particles.

Pleated or cartridge - thick and have a large surface area, so they're much more efficient than other types of disposables. Many only have to be changed once a year, making them cost-effective.

Washable - pull the filter from the unit, wash with water, dry and re-install. These require more effort but are friendlier to the environment.

There are two types of washables - electrostatic and non-electrostatic. Electrostatic filters contain tiny fibers that act like magnets, attracting small particles that other filters allow to pass. Some electrostatic filters come with a lifetime warranty.

If your filter is in a hard to access location, buy two washables. You can switch them out rather than having to wash the filter and make a return trip to re-install it.

Electronic - the most efficient at removing particles from the air. The plates of an electronic filter are negatively charged and attract the positively charged dust particles. Electronic filters are the most expensive and are not do-it-yourself projects, but may be very helpful if people in the home suffer from allergies.

When shopping, look for the filter's Minimum Efficiency Reporting Value (MERV). MERV ranges from one to 16 with the higher numbers meaning better filtration.

Read other articles from The Walton EMC Gasette:
Five Carbon Monoxide Myths
Do you know what's true and what's not?