Where Can I Find The Model And Serial Numbers For My Heating System?
FAQ , Air Handlers , Mini Split Systems , Other Modified: March 19, 2026
You can find the model and serial numbers (M/N and S/N) for your furnace by removing the top-front service panel and looking to the left side of the interior cabinet or the top of the blower deck, depending on whether your system is an 80% or 90% AFUE unit. Also, the orientation (horizontal or vertical) and flow direction (down or up) of your furnace may impact the location of the information. 
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