This is an article that discusses the way that a hot water heater operates. It covers how the water is kept hot, and how a water heater is designed.
Most people have wondered at least a time or two about how a water heater is able to keep hot water pouring from the shower head for the duration of our morning shower. As devices go, the method that a water heater employs to get this done is very simple. For about 75 years, the basics of the water heater have not changed.
All tank-type water heaters have the same common elements. The first and most obvious thing about a water heater is the tank. These can range from 10 gallons up to over 100 gallons. The tank is where water is stored while being heated and held until it is sent out to some open hot water faucet. Water heaters require two water pipes. One to let cold water into the tank and a second to carry hot water to where it is needed. Every water heater has a pop off valve that releases if the pressure in the tank gets too high and a drain to let the water out of the tank for repairs or replacement.
The final common component in a hot water heater is a way to heat the water. This is done most often by gas or electricity. With gas, the water heater has a burner at the bottom of the tank. With electricity, the water heater has two or more heating elements that are located inside the tank. Solar, wood, and other methods are used at times to replace gas and electric as the fuel source.
When cold water enters the water heater holding tank. From the water inlet pipe that extends above the top of the tank, a tube runs down to near the bottom of the water heater inside the tank. This way, cold water is delivered to the lowest part of the tank. Since cold goes down and hot goes up, this limits the amount of cooling that happens when cold water enters the tank. It also tends to help the heating process for the lower electric element and the gas burner by putting the cold water right where most of the heat is being generated.
As cold water enters the tank, it forces the hot water out. Just below the where the hot water connects to the top of the tank is a short pipe that allows the hottest and therefore highest water to exit from the hot water heater. This works to make certain that the hottest water possible is delivered to where it is being requested by an open faucet.
Hot water heaters also come with one additional feature. They all have a thermostat. This is a device that can be set to regulate the water temperature. The water inside a hot water heater can be maintained between 120 degrees F and 160 degrees F. Some heaters will give a wider range than this. However, most homes operate well when the temperature is set between 130 and 140 degrees F. Above 160 degrees F, the danger of explosion begins to increase.