Abstract: A water tempering system comprising a mixing tank located downstream from the main hot water storage tank, the mixing tank receiving a supply of hot water at a first temperature and a supply of cold water, the hot water and cold water supplies mixing within the mixing tank to provide a source of tempered hot water at a reduced, second temperature that is discharged from the mixing tank for distribution and use within an overall system. The amount of cold water directed to the mixing tank is controlled by a variable frequency drive pump which can adjust depending on system demands to ensure that sufficient cold water is directed to the mixing tank to ensure adequate mixing occurs to bring the temperature of the hot water to the second reduced temperature even during periods of low demand.