Formerly a single packaged unit, the Unico System M1218 air handler is now a separate module, making the already small unit more adaptable for installation in tight spaces. The M1218 air-handler unit consists of various modules that are easily latched together. The modules can be arranged in vertical-up-flow, vertical-counter-flow and horizontal-flow configurations. They can be combined as heating-only, cooling-only, or heating and cooling. Unico System made this change after receiving feedback from its Unico Preferred Contractors. Single packaged units are still an option with the Unico Vertical Air Handler Unit (V-AHU) series for installers needing combined units for closet installations and small mechanical area projects.