Electric Water Heaters have a heating element that is immersed in water. The heating element heats up as the electricity passes though the element, the heat is transferred to the water making it hot. This is a very efficient process but at normal voltages 240 volts very slow.
A Modern Electric Water Heater has two elements and two thermostats the reason for this is that if both elements were on at the same time the heater would draw about 40 amps which would blow most circuit breakers. To remedy this they installed two thermostats that work like this: when the top thermostat gets cold it turns on the electricity to the heating element which heats the water at the top of the tank. when the water at the top of the tank gets to temperature it shuts off and diverts the electricity to the lower thermostat if the water is cold in the lower part of the tank the thermostat supplies electricity to the lower element. when the water reaches temperature in the lower part of the tank the thermostat turns off. Now the tank is full of hot water.
When You Use Hot Water the water at the lower portion of the tank starts to get cold the thermostat turns on and energizes the lower heating element and starts heating the water. If the hot water depletes faster than the bottom element can heat the water and the top thermostat starts feeling a chill it will turn off the bottom element and energize the top element allowing for the fastest way to heat the water.
The Cold Water Inlet pipe is on the top right which allows cold water to enter the heater, notice attached below the cold water inlet is the dip tube this directs the cold water to the bottom of the tank pushing the hot water to the top of the tank and out the hot water outlet on the top left of the tank.
The Temperature Relief valve is located on the top of the heater or TPR for short it's job is to relieve the pressure in the tank to prevent explosions in case the pressure gets to great (150 lbs) it will also open up if the temperature exceeds 200 degrees and allow the heater to cool down. When the TPR opens up it expels lots of very hot water it is important that the TPR has a pipe directing the water to a safe place typically the pipe should be approximately 12 inches off the ground or garage floor.
The Anode Rod is a solid pipe made of aluminum or magnesium and prevents the tank from deteriorating. Most water heater tanks are made of steel when the tank is filled with water a electrolytic process begins, the anode protects the tank by being a better electrolytic conductor thus giving of itself to protect the tank. Eventually the anode will be consumed leaving the electrolytic process to deteriorate the tank. find out more about his in maintenance
The Drain Valve is just that the valve to drain the heater during maintenance and repairs |
