HeatherB

Thank you very much for your detailed response. I had the furnace cleaned and they couldn't tell me there where two filters. What we are looking to do is to move the furnace from the closet in the house to mount it horizontally in the crawl space. It is a small house and we need the room. I will get someone to take a look for the pitting/rust that you mentioned to see if it would be worth moving this furnace or buying a new one. I estimate this one to be around 26 years old. Much appreciated.

I have an AIRCO WBS2-100/90 Serial # BJ-13080 and I can't seem to find what size filters it requires. Also, any information about the furnace and whether I should be replacing it would be greatly appreciated. Thanks, Heather