LIVONIA, Mich. — Hamilton Engineering was recently awarded a U.S. Patent for their Cold Water Injection System (CWIS™) contained within their Companion™ Water Heater and optional on all of their hot water storage tanks. The CWIS™ insures the highest efficiency possible in the water heating system by ensuring all of the coldest water enters the heater first, while eliminating any flow restriction or pressure drop on the hot water being supplied to the laundry so common with other instantaneous or on demand water heaters.