We are selling a used York Model 3G124-20G HVAC UNIT. We pulled it from a commercial building that we sold. We will garranty the unit to be good when you install it. The York model 3GI24-20G appears to be a commercial packaged HVAC unit, likely a gas/electric model (indicated by "G"), possibly 3-ton (24 for BTUs, 20 for tonnage in some codes), using R-410A refrigerant (older code), offering efficient heating and cooling with features like low sound and energy efficiency, designed for businesses but sharing technology with modern York residential systems that use low-GWP refrigerants.