Arrived at our clients home for two system heat maintenance inspection. Our client provided me with new filters to be replaced today. Once the filters were replaced at proceeded to test and inspect the fire safety shut off for both units. I clean both flame sensors, pressure switch ports, and furnace cabinets for both units. Our client is in the process of selling her home and I mentioned that the downstairs older unit may need a sediment trap added to the gas line for the furnace. To have this installed today to help bring the furnace up to code. As a courtesy also I did cut back some roof Material that was close to the flue pipe of the furnace. Everything is working and heating properly on departure.