How do I know If my HVAC Air filter is dirty or not?

Answer 1

you been through how many years of education?

Answer 2

A visual inspection is usually sufficient

Answer 3

Look at it. You'll get 1 to 3 months out of a filter. The cleaner the filter the more efficient your unit will run and the less stress you unit will be under which will help extend its life.  

Answer 4

hold it up and look at it. if you can't see through it, it's dirty

Answer 5

Visual inspection.  

Answer 6

you take it out of its slot, hold it up toward the light and look at it.  since you'll have [one assumes] a new, clean filter of correct size handy, you can compare the two ...  -- grampa

Answer 7

Look at it.   You'll get 1 to 3 months out of a filter. The cleaner the filter the more efficient your unit will run and the less stress you unit will be under which will help extend its life.  Its lot cheaper to replace your filters "to soon" than replace your system earlier than needed.

Answer 8

Turn it on. If you look like an extra from Porgy and Bess after a few minutes, it is time to clean it.

Answer 9

if you can use a spoon and scoop up dust on to the spoon

Answer 10

Shine a light on one side of the filter in a dark room.  If you cannot see the light on the other side, the filter is dirty and needs to be replaced.