Lennox International makes and sells residential and commercial HVAC equipment and services exclusively in North America, having exited its European operations in late 2023. On the residential side, Lennox sells central heating and cooling systems — furnaces, air conditioners, and heat pumps — under the Lennox, Armstrong Air, and Allied brands. Roughly 80% of residential demand is replacement of existing equipment, making it relatively resilient. On the commercial side, Lennox sells rooftop units and split systems for light commercial buildings, provides installation and maintenance services for national account customers through its National Account Services business, and manufactures refrigeration equipment for supermarkets and industrial customers under the Heatcraft brand. Lennox operates two segments: Home Comfort Solutions (~64% of revenue) and Building Climate Solutions (~36%). A key differentiator in Lennox's business model is its direct-to-dealer distribution network: ~70% of residential sales bypass third-party distributors and go directly to installing contractors through company-owned wholesale branches, allowing Lennox to capture both manufacturer and distributor economics. The remaining ~30% of residential volume flows through independent distributors. Profitability is driven by volume (high fixed-cost manufacturing), annual price increases, mix shift toward higher-efficiency products, and attachment of high-margin parts and accessories. Lennox is actively expanding into ductless mini-splits via a JV with Samsung, heat pump water heaters via a JV with Ariston, and commercial emergency replacement, while growing its parts and accessories business through bolt-on acquisitions including Supco and Duro Dyne.