Return Air Filters?

[nuthut]

I noticed neither of my furnaces or A/C units have a return filter. They are all Duo Therm brand units. I also cannot find a place to put the filters inside the units. Should there be filters on the air return? I would think so.

[11B]

Marv, if your worried about return air I would suggest that you take off the grills and affix some cheese cloth to the back of them then replace. This will not hamper your air flow and allow you to rest easy about the filter problem.

[nuthut]

I don't know if I should be worried or not. Does anyone run them? If they are not designed to have filters, I guess I am not worried.

[RayChez1]

I have return filters on both of my ac/heat pump. It should have a grill that can be removed.