How to replace electric heating elements on the water heater. See what the most common causes of the water heater element failure are, testing tips, and solution.
Most of the electric water heaters have two heating elements, upper and lower, where the screw-in type is the most common type. Water heater element with the flange is another type but is used less. Both types are immersion type elements, U-shaped that heat water when energized with the electricity.
will use various types, which are different in voltages and watt
densities, where 240 volts and 4500 watts are the most common. These
two values can be checked on the rating plate on the water heater.
The thermostat setting is what allows the heating element to provide more or less power or lower and higher temperature of the outgoing water.
When selecting the best electric water heater for your home, you will have an option to buy a unit with low or high watt density elements. Low-watt density heating element is what you should look for, as it has an even distribution of heat, which makes it last longer.
Note: keep in mind that the electric heating elements with the higher wattage require more Amps and heavier gauge wire.
If you live in the area with the hard water condition, you probably had problems with the mineral deposits and limescale. The
sediment build up on the water
heating elements will prevent the heat transfer to water at the proper
rate, thus overheating and causing the burnout.
The solution to this problem is to clean the electric water heater
element regularly, by brushing away the scale build up. Another option
when selecting a new water heater is to buy a unit with the Incoloy
type which lasts longer and have better resistance to the sediment
Dryfire problem happens when the water heater elements while working, are exposed to the air pockets. The part which is in contact with the air will get an excessive amount of heat. It takes several seconds for the copper heating element to burn out. They are designed to operate only when submerged in water. The dry-firing can be recognized as the element shaft is annealed so soft that you can bend it with your fingers and the plastic element is melted.
The recommendation is always to fill the tank and bleed all the air from the system before turning the power ON on the electric water heater. The problem is not covered by the manufacturer's warranty.
If more than the design voltage is supplied to the heating element, the element will burn out. One of the examples is the high voltage during the lighting or sometimes caused by the electric utility company. If there is less voltage provided, the heating element will work but will be less efficient.
Other problems that might affect the proper work are related to the vibration break, open circuit or split sheath.
For the screw-in type heating element as the most used type, a long socket wrench is needed for the removal and installation.
Turn the water heater OFF on the electric service panel.
Locate the broken electric heating element and make the access by removing the insulation and cover.
Make sure that the power is OFF by measuring the voltage on the thermostat terminals, which powers the element.
Shut OFF water supply and drain water below the broken element.
Disconnect the wires and remove the broken part by using the correct tools.
Install a new gasket and the heating element.
Reconnect the wires and make sure they are snug and clean of debris and rust.
Fill the tank up.
Resume the power.
An open element means that the electric current cannot flow so there is no heating.
Turn the power OFF on the electric panel and check the voltage by using the multimeter.
Remove the wires from the terminals.
Use the multimeter (set to OHM settings) and place the probes on screw terminals. If there is no resistance, the circuit is open and heating element needs to be replaced.
Turn the power OFF to the water heater. Double-check the voltage on terminals by using the multimeter (just in case).
Disconnect the wires from the heating element.
Set the multimeter to OHM settings.
Put one test probe on the terminal and the other probe on the steel tank. If the OHM multimeter shows any readings, the element is grounded and needs to be replaced.