A heating/cooling plate device for heating and/or cooling an object through a range of operating temperatures extending both above and below ambient. The device having a heating element to heat the plate, and a vapor compression refrigeration system through which refrigerant flows to cool the plate. Greater control of the heating and cooling of the plate is achieved by positioning the heater element substantially at the exit of an expansion valve of the evaporation compression system as this provides thermal energy to the refrigerant as it enters the evaporator.