Dirty Air Filter Costs Money

Dirty Air Filter Costs Money

Be sure to click through to the rest of the article there is some fasciating figures about the added cost a dirty air filter adds to the cost of running your furnace.

Dirty Air Filters May Cost More Than You Thought

ST. PETERSBURG, FL -- (MARKET WIRE) -- 10/17/2005 -- In the few minutes that it takes to change your furnace or air conditioning filter, you might cut your electric bill by as much as $10 this month. Or $20. Or $80 or even more, depending on the type of filter you are using and how much you run your system.

Power company websites mention changing air filters as one way to save energy. If not maintained, that little filter could be one of the biggest energy wasters in your home. That's according to calculations derived from the ASHRAE (American Society of Heating Refrigerating and Air Conditioning Engineers) Handbook.

The calculations take into account your fan motor's efficiency, the cost of electricity in your area, airflow resistance of the air filter and the amount of time the fan motor is in use. For those of you with a technical mind, the formulae are presented at the end of this article.

The one value in these formulae that changes most frequently is the airflow resistance of the filter. Every filter has a certain amount of airflow resistance and dust building up on the filter eventually begins to block airflow. The longer the filter is used, the more dust it catches, the more it blocks airflow and thus...the more electricity it wastes. That's why electric companies remind us to change our air filter on a regular basis.

--More on Air Filters--