Lennox gas fired furnace question

I recently inspected a home with a Lennox gas fired furnace installed. I can’t seem to find any details on this unit from the usual sources so wanted to know if anyone out there could perhaps provide the age of the unit. I attach a photo of the only data plate available. I note that it is a 3 ton unit but that’s about it… Any help appreciated.

that appears to be the data plate of the evaporator coil…that’s not going to be much help in verifying the age of the furnace…

The put most of the information inside the burner compartment

Unfortunately no other data plates on any parts of the furnace or enclosure. Just grasping at straws using the photo supplied. Seller advised that the furnace assembly was installed around 10 years ago but no real way of verifying. Thanks anyway.

Was it natural draft, assisted draft of condensing type? If you don’t know what this means take the internachi advanced HVAC course.
Lennox furnaces have the date in the serial number, many also have the actual date, rating plates with this information is found in the burner compartment.
If everything is gone or unreadable comment on the condition of the stuff you see.
Lennox also sold a type of furnace they called a pulse. It had lots of problems, there probably aren’t many left anymore. Pulse were supposed to be high efficient, their combustion process was similar to what the Nazi’s used for V1 rockets. Some were combination furnace and water heaters. An experiment that failed.