Came to residence for prepaid MSC tune-up on a '98 Bryant furnace located in the basement. Equipment functional upon arrival. Upon inspection, I found that both 16x25x1 filters in the furnace we're dirty. I replaced one with a plastic-framed homeowner provided filter. All other electrical, mechanical, and gas components are operating properly and within manufacturer specifications at this time. See health report card for any specific information. Homeowners expressed interest in a duct cleaning. I have little knowledge regarding this so I told them I'll have the office call and figure out an estimate for them. Equipment functional upon departure. Thanks for your business and have a great day!