A heater module is described that includes a heat distribution plate including a bottom portion having first and second sides and a plurality of projections extending away from one of the sides. A heat source is provided for heating the heat distribution plate, and, optionally, a heating tray can be used to receive the heat source and heat distribution plate. The heater module is adapted to engage a sample purification tray having a plurality of purification and/or discharge columns which can extend through openings in the heater module and direct a sample into a sample receiving tray. Methods of heating samples using the heater module are also described.