On Wednesday, September 30, 2015 at 4:49:16 PM UTC-4, Tony Hwang wrote:
Bill Gill wrote:
Everybody says to inspect your furnace filters, but they don't say what
to look for. On the TV news they always say it, then show a filter that
is completely clogged. Obviously they should be replaced before that.
So what should I look for to decide if I need to replace them. I have
been replacing them every 3 months, but when I do I can barely tell
the difference between the old ones and the new ones.

Bill

Do you check air filter in your car? Likewise see it against light or
sun.

Filter"s" (plural)

I wonder how many people don't even know that there is a cabin air filter in their car.

I have bought 4 used cars in the past three years (3 in the past 12 months) and everyone of them had a fairly clean engine compartment filter but a cabin filter that was black and filled with leaves, bees and other debris.