I've got this problem in my house, it is a 1 story with central air
and gas heating system by Lennox. The other weekend, I noticed that
there are small tiny brownish-reddish color particles all over my
computer monitor. My computer monitor sit directly beneath an air
vent. Because the monitor is directly beneath the vent and also
because the color of the monitor is white, therefore, I can easily see
those tiny particles.
I open the air intake filter door (20 inch X 30 inch), the one that
is in the wall, took out the air filter and look behind it. I noticed
there is a big dead cock roach in it. I then vacuum it out. Within
the next day, the amount of those strange particles which fallen on
top of my computer monitor has significantly decreased. It has been
one week since I got that roach out, now I only see two or three tiny
flake like particle each day on top of my monitor. Before I remove
the roach from the air return duct, there were a lot of those strange
particle. This happens during both air conditioner or heater
I just hope that those small particle is the roach's body parts like
the wings etc... I also hope that it is not rust blowing from my
vent. Could it be possible that rust can be blowing from the vent
It is hard to tell if I see those particles blowing out of other vents
in my house because the only reason I noticed those tiny particles in
that particular room is that my white computer monitor sit directly
beneath the vent and that vent is about 5 feet away.
When I look in that space area behind the air filter, I noticed there
are some gap/tiny cracks and I want to find ways to seal it so that no
other insects will crawl into it in the future.
My questions here are:
1) based on the problems and symptoms I described do you think those
particles is from that roach or other insects may be stuck somewhere
in my AC/heating system or is it rust in my system that is blowing out
of the vent?
2) How do you seal these area in the air return duct which is behind
that big air filter on my wall? What to use (joint compound, caulk,
foam sealant etc..)
a) small gap where the drywall meets the concrete floor
b) tiny vertical crack at the corner where two vertical dry wall
c) Where the 4x2 wood meet the foam insulation sheathing.
Thank you very much in advance.