A steam turbine includes a shaft operatively connecting a first turbine section and a second turbine section. A packing assembly is positioned about the shaft. A first conduit is fluidly connected to the packing assembly. The first conduit is configured to introduce a flow of low temperature, low pressure steam to the packing assembly. A second conduit is also fluidly connected to the packing assembly downstream from the first turbine section and upstream from the first conduit. The second conduit receives a portion of the high temperature, high pressure steam passing into the packing assembly from the first turbine section. A valve is fluidly connected to the second conduit. The valve is configured to be selectively operated so as to allow the high temperature, high pressure steam to mix with the low pressure, low temperature steam in the second conduit.