Taco Hot-LinkPlus reduces the time it takes for hot water comfort to reach showers and faucets. The Hot-LinkPlus features a smart circulator that learns household hot water usage patterns and makes hot water available at the same times the following week. If water usage changes the Hot-LinkPlus circulator adapts for you. It never needs programming When no hot water usage is detected there's even an automatic vacation mode. The average family can save up to 12,000 gallons of water per year and it's easy to retrofit to an existing plumbing system. Designed for plumbing systems that do not have a dedicated return line.