Im a girl---where do you replace the filter... took off the pannel and seen an old filter from the prev tennants... yuck.. needs new one.. looked online for the proper size and it said to use a 14x25.. went and got one at our locale Ace.. now I cannot get it in there. Any suggestions? Is it even supposed to go where I found the old one? It was between the return and the furnace area.

W hy don't you have the landlord do it? What did you do to remove the old one? It either slides in or slips in and yes, where it is located is the normal place. Some filter assemblies require you to push the filter in to compress a spring and then it slips in and the spring holds it in place.

Try a big box store like Lowe's, Home Depot or Menards but you also need one more measurement. The thickness can vary from 1-4", yours islikely a 1" but you must know for sure. I agree with ma0641, this is not something a tenant must do.