This is one of those chores most people know they're suppose to do, but few remember.
WHAT
Replace the air filter on your furnace.
WHEN
Now, and again in three months (this is minimal for the average home).
WHY
Because a dirty filter restricts airflow through your heating system. Reduced airflow can mean uneven heating or cooling, increased fuel bills, and added stress on your furnace
HOW
Locate the filter. It's usually where the cold air enters the furnace, near the fan section (see the diagram). At this location, the air is flowing into the furnace. The airflow arrow on the filter should point toward the furnace.
Slide the filter out and not its size. It's written on it somewhere. Buy half-dozen filters from the hardware store.
Replace the filter now and check it monthly. Replace it as needed, but at least every three months. The rate at which they get dirty depends on the number of people, pets and amount of dust in your home.
.
TIPS
Mark airflow direction on the ductwork with a market so that it will be easier to remember the orientation of the filter the next time.
you may want to have the ductwork cleaned to remove the previous owner's debris. Once is enough though -- don't get talking into doing it annually.
Consider an electronic air filter if you have a family member who suffers from allergies or one who smokes. They do a great job of taking very small particles out of the air. But remember, because they do a better job of cleaning, they get dirty faster. They should be cleaned once a month.
We hope this has been helpful to you.
-The James Silver Team