Waiting for Hot Water
With a tank type water heater hot water is sent out from the heater to your faucet or appliance. As the hot water sets in the pipe waiting to be used, it cools off.
When you turn on the hot water faucet, all the cooled off water has to be displaced with fresh hot water from the water heater. This can be a lot of water volume in the pipes to replace, especially if the faucet is far from the water heater. The fresh hot water also has to warm up the hot water pipes before you get the full temperature of hot water you want at the faucet or appliance. This can take several minutes, wasting water, energy and time.

