Repair and Maintenance: Who is Responsible for Covering Wall Unit Ac's in the Winter

My question involves landlord-tenant law in the State of: NY

There are two wall unit AC holes in the apartment I rent. When I originally moved in, both had a back covering screwed in, the bedroom unit also had a plastic garbage bag covering the hole as well. The kitchen one just had a back covering. I moved in during spring/summer so it was never a big issue, now that winter is here there is cold air seeping through because it just isn't effective at completely covering the holes.

I put the screwed in cover in the kitchen AC in, but left the actual AC in as well for maximum blockage (landlord did not provide AC's when we moved in, they are my own AC's just FYI) , but obviously air is still coming in. I put another garbage bag over the bedroom one for now, but it is constantly making noise, and still cold in the room.

I've found some proper covers online but they run about 150 bucks each. I don't have the extra money right now to pay for that, and I'm not sure if I am even the person responsible for it? I haven't asked my landlord yet because I want to find out if he is even the one responsible. If he is, is there a minimum standard he has to abide by? I'm nervous he will say that the coverings are effective (when I know they're not).

Thanks for the help in advance.

Repair and Maintenance: Who is Responsible for Covering Wall Unit Ac's in the Winter