Ruud Heating/AC Unit Can't Find Filter? I know I must sound resembling a moron, but I cant find...

I know I must sound resembling a moron, but I cant find my filter in my heat unit. Actually I know where on earth one filter is but it sort of looks like a peak window, that you rinse past its sell-by date. But I think I am supposed to own another filter that you are supposed to actually replace next to new ones every 3 months or so- but I cant find it. At lowest possible I had one of those next to my old part. Am I totally off foot? Is the screen item all I enjoy or is there another filter lurking somewhere assembly dust and getting ready to blow up?
How do you gain corgi registered for gas...
Answers:    try taking the bottom door stale the furnace and checking the side where the duct is tied into to see if it is mounted inside the furnace.
No hot wet pressure contained by the entire...
That eyeshade thing is it. They don't stop closely of dirt though. You should replace it with a correct quality filter. For more info, check out the heavens filters page at www.hvac-for-beginners.com