Innovative hot water recirculation systems deliver hot water to fixtures quickly without waiting for the water to get hot. Rather than relying on low water pressure common in most water lines, recirculating systems use a pump to rapidly move water from a water heater to the fixtures.

In this system, a recirculating pump rapidly pulls hot water from a water heater while simultaneously sending cooled-off water from the hot water lines back to the water heater to be reheated. In addition to having the convenience of hot water on-demand, the system conserves water and can save energy.

Hot water recirculation systems can be activated by the push of a button, or by a thermostat, timer or motion sensor. Systems that use a thermostat or timer automatically turn on the pump whenever water temperature drops below a set-point, or when the timer reaches a setting. These systems ensure that hot water is always available at the faucet without any waiting.

Systems that use a thermostat or timer may use more energy than on/off button or switch operated systems, due to more frequent recirculation cycles and hot water constantly being left in the pipes to cool off.

Hot water recirculation systems generally consist of a pump, an integrated electronic controller, and a zone valve. When the activation button is pushed, or when another type of control turns the system on, the pump starts recirculating cooled water that's been sitting in the hot water line and sends it back to the water heater through the cold water line. When the water reaches a desired temperature a control closes the zone valve and turns off the pump. It is much like turning on the hot water faucet and letting the water run until it gets hot, but instead of the water going down the drain, it is simply returned back to the water heater. When the hot water faucet is turned on, hot water is readily available.

The system is designed to provide hot water at the most distant fixture and every fixture in series or close to the main line. All cold water fixtures still receive cold water, and the system is designed to not allow hot water to enter cold water lines. Only one pump is necessary to supply hot water to any fixture. Optional wireless remote control units let the user turn on the system from any faucet or fixture in the house.