Air Conditioning Help
I just bought a house, and I have a simple yet perplexing air conditioning problem. I can't find the filter. Hmm. Alright. Once you stop laughing, maybe you could help me out. I have two Lennox CBS18 Series air handlers mounted in the attic, with flexible ductwork running to each room. The installation instructions give me the helpful hint that "Filters are duct mounted and field installed." What am I looking for?
Answer:
I have seen filters located in the air handler unit itself, whereupon you must remove a panel or door to access the filter. I have also seen installations where the return air duct plenum had a grill near floor level, and you had to remove the grill to get to the air filter. Fortunately, this grill had thumbscreews so that no tools were necessary. It may be necessary for you to remove your grill with a screwdriver, so don't eliminate that possibility. Look for a replaceable filter just behind the return air register. The register should be wall mounted or on the ceiling and have thumb levers for swinging the grill open. There will probably be a course mesh filter internal to the furnace near where the return air duct enters the furnace. You may access this filter from a panel at the lower panel on vertical furnaces.