Abstract: A warewash machine sump collects hot cleaning water that is recirculated in the chamber during cleaning. A drain line is for draining cleaning water from the sump. A fresh water input system includes at least a hot water input and a cold water input. The fresh water input system has a common input line in communication with the hot water input and the cold water input. A cold water input valve and hot water input valve are provided. The drain line and the common input line are arranged in a heat exchange relationship. A temperature sensor arrangement is associated with the drain line for determining temperature of the cleaning water traveling through the drain line. A controller controls the hot water input valve and cold water input valve based upon the temperature sensor arrangement output.

Abstract: A warewash machine includes a housing at least in part defining a chamber for cleaning wares. A sump collects hot cleaning water that is recirculated in the chamber during cleaning. A drain line is for draining cleaning water from the sump. A fresh water input system includes at least a hot water input that receives hot water from a hot water source and a cold water input that receives cold water from a cold water source. The fresh water input system has a common input line in communication with the hot water input and the cold water input. A cold water input valve is for controlling input of cold water into the common input line. A hot water input valve is for controlling input of hot water into the common input line. The drain line and the common input line are arranged in a heat exchange relationship to enable heat from cleaning water traveling through the drain line to enable transfer of heat to water traveling through the common input line.