| Circulating pumps are often  used to circulate domestic hot water so that a faucet will provide hot water  constantly upon demand. Since water is piped from the water heater through the  pipes to the tap, once the tap is shut off, the water remaining in the pipes  cools producing the familiar wait for hot water the next time the tap is  opened. A circulator pump insures the hot water in the pipes is always hot,  minimizing the wait. 
                                  Turn off the house water supply.Open the hot and cold faucets at the fixture       chosen for installation. This will relieve the water pressure from the hot       and cold water pipes. Remove the shut-off valves that supply hot and       cold water to the sink from the ½" copper pipe. For ease of       installation, leave the compression ring and nut from the angle stop on       the hot and cold water supplies. Connect it to the pump-activator wire. |  |  |