Scratched flame sensor in Lennox furnace needs to be replaced.
Recommending a newer unit after a service call.The cost of repairing a 18 year old American Standard furnace with a bad heat exchanger maybe more beneficial to finance a nicer two Stage to match the needs of their home. Setting up a better time to come talk Lennox systems. The AC is also an older Goodman System that has seen better days.
Duct cleaning. Returned main supply lines and return line for both units. Returning in a few weeks to check the coolant levels on her AC unit