Is there a filter for my AC unit up in the attic?

[Schfifty Five]

I'm about to change my air filters too and was wondering if I had to change a filter out in the attic or just from the vents in the living room.

I counted 3 air return/intake vents (1 downstairs, 2 upstairs). If I just replaced the filters in there, is there any need to add/replace the filters in the two furnaces/coils in the attic? I don't even know if the coils in the attic have a slot for a filter to be honest.

 

[CPA]

I'm about to change my air filters too and was wondering if I had to change a filter out in the attic or just from the vents in the living room.

I counted 3 air return/intake vents (1 downstairs, 2 upstairs). If I just replaced the filters in there, is there any need to add/replace the filters in the two furnaces/coils in the attic? I don't even know if the coils in the attic have a slot for a filter to be honest.

A filtration system that is part of the furnace is an add-on. It is not standard equipment, so if you have filters in the return vents, then most likely you do NOT have a filtration system add-on to the furnace.