It's a dirty world out there. And sometimes the dirt, pollutants, and pet hair come inside where people live and breathe. That's when you should consider an air purifier. Unfortunately, an air purifier, like just about everything else, eventually stops running or isn't as efficient as it used to be. That's when it's time for a special meeting of the Fix-It Club!

 

How Does It Work?

Electronic air purifiers are simple in design and typically require only periodic maintenance following instructions in the owner's manual.

An air purifier is a small appliance designed to filter airborne pollutants from indoor spaces. Although dust is most noticeable where it settles and collects, the average home has about three million dust particles suspended in every cubic foot of air. Scary, isn't it?!

There are two types of air purifiers: the mechanical type and the electronic type. Both come in small-room and whole-house models. In a typical mechanical air purifier, a blade fan or a squirrel-cage fan draws air through a series of filters, including a prefilter (to remove the largest particles), one or more activated carbon or charcoal filters (to remove smaller odor-causing particles), and maybe a type of HEPA ( high- efficiency particulate- arresting) filter. Some mechanical units include an ion generator to charge remaining dirt particles, causing them to adhere to room surfaces.

The most effective kind of air purifier uses an electrostatic precipitator to remove very fine particles, such as cigarette smoke and pollen, from the air in a room. The precipitator gives air particles a positive charge and then traps them with a negatively charged grid. The purifier also may contain filters to remove dust and odors, as well as an ionizer to add negative ions to the clean air. The ionizer supplies a strong negative charge to one or more parts called needles. An intense electric field is developed at the point of a needle, and it creates ions in the atoms in the air. Positive ions are attracted to the needle, while negative ions flow outward. Don't worry, there won't be a quiz.

 

What Can Go Wrong?

Lots of things can go wrong with air purifiers. Fortunately, most of them are common problems that you can easily fix. The electrical cord may fail, the motor may fail, the switch may be faulty, the fan may be loose, or the motor shaft may be frozen. In addition, the precipitating cell may become dirty, motor bearings may be dry, filters and air intakes may be clogged or dirty, collector plates may be bent, and ionizer wires may be broken. You probably can fix any of these problems yourself.

Caution!

Do not operate an electronic air purifier or a mechanical purifier with ionizer needles in a room with oxygen equipment or where combustible gases are present. Also, handle a precipitating cell carefully; it contains sharp metal edges and delicate parts.