Diagram of how hot water recirc system works in a home with a tank style water heater.

The diagram shows how the water flows from the water heater to all of the fixtures in a home using a hot water recirc system to both speed it up and to not waste hot water down the drain.

The red line indicates the path that the hot water takes as it travels through a house. And the light blue line indicates the path of the cool water in the hot line as it is pushed back to the water heater.

When 65-degree water gets to the furthest fixture the Bridge Valve closes so that no hot water can get into the cold line. This process results in having hot water everywhere you want it, when you want it.