Heating, Air Conditioning, Fridge, HVAC/Info on age of furnace


I recently bought an old home and would like any info and approximate age of a Lennox gravity flow gas furnace (no ducts, just heats through a large heat register in the floor above it.) The model # is GN3-105S2. Any knowledge of this product would be helpful.

Thanks for asking Wendy but every manufacturer has their own method of dating a piece of equipment and I do not have these manuals. You will also need the serial number as this is what has the date code and contact Lennox and they can tell you the manufacturing date of this unit. Thanks J

Heating, Air Conditioning, Fridge, HVAC

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J Cook


With 25+ years experience, I am familiar with residential, commercial, and industrial HVAC equipment including but not limited to boilers, chillers, reciprocating and screw compressors. I am trained in all manners of control wiring.


I currently have three HVAC licenses and Refrigeration license by the State of North Carolina. I have been in this field for over twenty years. I have been a service technician for a contractor and also worked at a state college in the repair and maintenance of steam lines and equipment. I am currently the Building Maintenance Superintendent for a municipality.

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