17 Sep. 20

How Does a Hot Water Heater Work?

Most homeowners do not spend too much time thinking about their water heater. This is actually a good thing. As long as the unit is creating hot water, there is not too much to worry about. While this is true, it is smart to have a basic understanding of how this system works and what options are available when replacement is needed.

There are four basic types of water heaters to choose from. Each of these options has specific pros and cons. The most popular hot water system is the tank-type heaters, but tankless units are growing in popularity. Another option, hybrid models, is somewhat newer; however, they are worth thinking about for those who want to achieve a maximum level of energy efficiency. The point-of-use units are ideal for delivering hot water quickly to appliances and faucets that are located away from the primary unit.

Keep reading to learn more about how each of the tank options works.

Tank-Style Water Heaters

Many homes still use more traditional tank-type water heaters. Either electricity or gas powers these. Usually, gas water heaters are not as expensive as the electric options, but they will cost less to operate since gas is much more affordable than electricity. However, most experts agree that electric water heaters are much more efficient than gas models, and they have higher energy factor ratings.

Just as the name implies, the tank style heater has a bigger insulated storage tank that will hold the hot water until it is needed. This is how it works: the cold water comes in the bottom of the tank. A gas flame below the tank then heats it, or it is heated by the electric elements that are suspended on the interior of the tank. There is an adjustable thermostat that will be regulated and maintain the temperature of the water. There is also a pressure-relief valve that will prevent too much pressure from building up inside the tank.

When someone in the home turns on a hot water faucet or an appliance that requires hot water, the heated water will be pumped out through the top of the tank and through the hot water supply pipes in the home. As the water levels in the tank decrease, it will refill with  cold water automatically, and the process starts over.

It is possible to find tank-style water heaters in several sizes that range between 20 to 80 gallons; however, for most homes, a 40 to 50-gallon tank is adequate.

The Hybrid Water Heater

Hybrid water heaters also have a tank. They are equipped with an electric heat pump. This pump is always found mounted in the unit’s storage tank. This is also where the compact compressor and evaporator coil is, which has the job of capturing heat from the air in the room and move it to the cold water coming into the tank. This results in hybrid units using up to 60% less energy than a more traditional unit.

One of the main drawbacks of this type of unit is that it costs more. However, many people are willing to invest because it offers a higher level of efficiency. Hybrid units cost approximately twice as much as standard units do; however, for most people, those additional costs are more than recouped within three to four years thanks to reduced electricity bills. Also, thanks to local and state rebates for high-efficiency appliances, the recoup time is much faster.

The Tankless Water Heater

A tankless water heater is a compact unit that is mounted in the wall. They are designed to provide hot water for an entire house, not just one faucet. Sometimes, they are referred to as on-demand or instantaneous water heaters. Something many homeowners have discovered is that this unit does not have a bulky storage tank, which makes it ideal for homes with limited space.

This is how a tankless water heater works. The heater will sit, not doing anything until there is a hot water tap turned on in the house. At this point, cold water will be pulled into the unit, and the flow sensor will activate the gas-fired burner or the electric heating element, which is going to be warming the internal heat exchanger. When the cold water moves over the heat exchanger, it is warmed up to the desired temperature. This is when hot water exits the heater and moves directly to the appliance or faucet that demanded it – rather than the storage tank. The combustion gases that are created by a gas-fired unit are then exhausted through the dedicated vent pipe.

Point-of-Use Water Heaters 

Unlike the whole-house units, a point-of-use water heater is a tank-less, compact model that will deliver hot water virtually instantaneously to a specific location, such as a shower or sink. This style of electric heater is usually installed at a fixture that is located far away from the primary unit. The main selling point is that this unit will eliminate the annoyance of having to turn the tap on and then wait for the hot water to come. This type of inconvenience will waste time, energy, and water.

Most of the point-of-use units available today are just 10 inches by 13 inches. This means they can fit inside vanity cabinets, closets, and other limited space. These units are very reliable and may last up to 25 years.

Choosing the Right Type of Water Heater

When it comes to hot water heaters and the various units, there are many options to choose from. Take some time to learn more about the options here to find the one that best suits a homeowner’s needs. Sometimes, speaking with the professionals can help ensure that the right unit is found and purchased.

Being informed and knowing the right option for a home will ensure that everyone in the house has access to hot water when they need it and that the unit will work for many years to come. Remember, for any appliance to last, maintenance is needed, so keep this in mind.