Black particles coming out of the room air conditioner

You might try submitting this question here...
https://www.mitsubishielectric-usa.com/contact_us/

Area where "fresh" air is being pulled in is dirty, filter needs replacement, heat exchanger is old, a seal is old/torn, or mold is shooting out!
http://www.ehow.com/info_12016541_particles-blow-out-fan-air-conditioner.html

Usually direction is changed by pulling one of the chains, or there will be a small black switch where/near chains enter in to housing area.

Hi,
Chances are that the air filter is made up of a black sponge material and it is coming apart and blowing out all over...
Take the front grille off and check the air filter...

heatman101

The fan that blows the air blows through the heater coils before it blows through the A/C.As long as the heater doesn't come on, there is not much that can be done. ZCooking the attic room will be a problem because it is the heat rises thing, and on top(literally) of it all, the roof is radiating heat.

it is not normal either the filter is blocked or your low on charge

maybe the filter needs to be cleaned?

Hi there,

The black residue is what is in your air. The reason for it to cling to the walls is the Ionization process that the machine creates. The ionization is to create a clean breathing space, free from contaminants. All particles floating in the air will be negatively charged and cling to each other or to objects in the room (like walls) that are positively charged.

If you cook, there is some smoke created, or when you burn candles. These greasy particles will stick to the wall or to surfaces. Cleaning them up regularly might help. You can also try another product from EcoQuest called EcoH which is based on enzymes and cut through that grime easily. That might take the black stuff off the walls.

Dutch

that is foam insulation around the seal of the evaparator box pull the unit from the wall remove the cover to get to it and clean or replace it

remove the filter aand run it and see what happens, the filter still could be causing the issue