Article Originally Posted on WaterHeaterStore.co
The electric water heater is not as common as a gas water heater, but you’re sure to run into one if you are in the construction or maintenance industry. They can be installed in homes or large commercial settings. If you’re familiar with a gas water heater, the electric water heater is not all that different. But there are some very fundamental differences worth being aware of.
Electric Water Heater Systems
An electric water heater has a fairly straightforward design for getting water hot. The basic components usually include:
- Water tank
- Heating elements
- Water intake/outtake
- Safety systems
We’ll go through each and look at how these systems work together. This will help you with your own problem-solving efforts if you’ve run into trouble.
Electric Water Heater Process
The electric water heater is a relatively simple device. Cold water is pumped into the lower part of the tank (if it has a tank), where a heating element gets the water hot. Many have a second heating element towards the top of the tank to improve efficiency.
Once the water is heated, the hot water naturally flows towards the top of the tank in a process called convection. There, the hot water is pumped throughout the building as needed.
Safety systems are built in to prevent the water from getting too hot or the tank from rupturing if too much pressure builds up.
Electric Water Heater Tank
Not all electric water heaters have a tank. Tankless water heaters are becoming more common in areas where there is not a lot of space or hot water is needed on demand in large volumes. But in most cases you’re more likely to find a tank-based electric water heater.
The primary function of the tank is to hold the hot water and to keep it hot as long as possible. The more efficient the tank, the less reheating of the water is necessary.
Electric Water Heater Heating Element
Electric water heaters often have two separate heating elements. The larger of the two will be in the bottom of the tank. It will have a thermostat in close proximity inside the tank that regulates how hot the water can get.
A second heating element may be in the upper part of the electric water heater. Also connected to the same thermostat (and sometimes with its own), this second heating element is designed to improve efficiency of the system. Because electric water heaters may not be able to efficiently produce as much heat as a gas water heater, a second heating element helps keep the water in the whole tank hot. This can also speed up the heating process when a lot of hot water is needed.
Electric Water Heater Intake/Outtake
In the typical electric water heater system, cold water comes into the bottom of the tank where it is heated. The hot water naturally flows to the top where the outtake part of the system distributes the hot water throughout the structure.
Electric Water Heater Safety Systems
Since electric water heaters need electricity to heat the water, losing power is not nearly as worrisome as that of gas water heaters, which may continue to heat water after power outages.
The electric system can therefore rely on automatic safety systems for the most part. The thermostat is the heart of the safety system and will turn the heating element off if the water gets too hot.
In rare situations the thermostat fails and the water is able to get too hot, possibly even to the point of boiling. Electric water heaters have a passive safety system that allows for excessive pressure to be released into a drain system. A pressure valve at the top of the tank allows this any excess water to drain in these situations.
Other Electric Water Heater Components
Some of the other parts you may find on an electric water heater can include solar panels and advanced monitoring systems. Solar panels can be used to heat the water either by directly heating water or by using electricity to run the heating element.
Advanced monitoring systems are typically designed to monitor the temperature and efficiency of the electric water heater. In some cases, the systems may be able to alert you of problems such as water temperature remaining too low or getting too hot.