Water heaters are an essential part of all homes and most commercial properties. No matter the type of water heater you have in your home, you need to schedule routine maintenance with a professional plumber. Proper maintenance just might be the single biggest factor that determines how long any type of water heater lasts, and this article will explain why water heater maintenance is so important and what it entails.
Average Water Heater Lifespan
The average lifespan of a water heater varies depending on the type of unit and the fuel source. Gas storage-tank water heaters have the shortest life expectancy at around eight to 12 years. The life expectancy of electric tank water heaters is a bit longer at around 12 to 15 years. If you want a water heater that lasts much longer, a tankless unit is definitely the way to go. A gas or electric tankless water heater will usually last a minimum of 20 years. Many units will even last for over 30 years since most of their components can easily be replaced if they fail, which isn’t true with tank water heaters.
One important thing to understand is that these numbers are simply averages and are based on the assumption that the water heater is properly maintained at least once a year. If not maintained regularly, all water heaters, and especially tank units, are prone to various issues that can greatly shorten their lifespan.
The reason that tank water heaters don’t last as long is that the water they store causes the tank to rust and corrode over time. This can eventually lead to the tank leaking. Tank leaks cannot be repaired, and the unit will need to be replaced if it’s leaking. Rust and corrosion in the tank are examples of why annual maintenance and inspections are so important.
Maintaining a Tank Water Heater
The most essential part of maintaining a tank water heater is to drain and flush it. Flushing is done to get rid of all of the sediment that naturally forms when the water inside the tank is heated. Water always contains some amount of dissolved minerals like magnesium and calcium. When the water is heated, some of these minerals precipitate or solidify into small, hard chunks of sediment that settle at the bottom of the tank. How much sediment forms and how quickly the sediment layer builds up inside the tank depends on how hard the water is. Hard water contains a much higher concentration of minerals, which leads to greater sediment formation.
Flushing the water tank should be done at least once per year. However, it is usually better to do it semiannually or every six months if your home has hard water. The water in the Denver Metro area ranges from relatively soft to moderately hard depending on where you live. The water in Denver itself is fairly soft whereas some suburbs like Aurora, Arvada, and Thornton have harder water.
One reason that flushing out the sediment is so important is that the sediment layer can greatly reduce a water heater’s energy efficiency and make it heat less effectively. This is especially true for gas water heaters. Gas water heaters heat from the bottom, and the heat from the burner flows through the tank and out into the water. When there is a thick layer of sediment present, that sediment ends up absorbing the heat, which will lead to the water heating more slowly. As the sediment absorbs heat, it also creates hotspots that can weaken the tank and potentially lead to leaking.
The lower heating element in an electric water heater isn’t directly at the bottom of the tank. However, the sediment can eventually build up to the level of this heating element if the tank isn’t flushed often enough. When this happens, the unit will heat much less effectively and the heating element could wear out more quickly.
The other most important part of maintaining a tank water heater is inspecting the anode rod. Any water heater with a steel tank has an anode rod inside the tank that prevents or at least limits corrosion. Units with a stainless steel tank don’t need an anode rod since stainless steel is resistant to corrosion.
An anode rod consists of a steel wire that’s around four feet long and is coated in aluminum, magnesium or zinc. All three of these metals are much more reactive than steel. The minerals in the water would normally react with the steel tank and quickly begin corroding and eating away at it. Since the coating on the rod is more reactive, the minerals corrode the metal coating instead of reacting with the steel tank.
The problem is that this process slowly dissolves or eats away the coating on the anode rod. When most of the coating is gone, the metals will start corroding the tank. This is why the anode rod in a water heater typically needs to be replaced approximately every five years or potentially even sooner if the home has hard water. If you don’t have the anode rod inspected every year and replace it as needed, the tank will corrode more quickly and shorten the life of your water heater.
When maintaining a tank water heater, a plumber will also perform a full inspection and make sure that all of the components are working properly. If you have an electric unit, you will usually need to have one or both heating elements replaced at some point. With a gas unit, it is important that the burner is cleaned regularly since it will produce much less heat if it’s dirty. Another essential task when maintaining a gas unit is to check the exhaust flue and ensure the unit is venting correctly so that carbon monoxide can’t leak out.
Maintaining a Tankless Water Heater
Tankless water heaters require much less maintenance than tank units. A plumber will always check the condition of the heat exchanger as well as either the burner or electric heating elements. However, the main thing that needs to be done is to flush and descale the unit. Descaling is important for removing any mineral deposits that have built up around the heat exchanger. When a tankless water heater has lots of limescale and mineral deposits, it will no longer heat as effectively. This leads to increased energy usage and can eventually prevent the unit from heating the water as hot as you want. The lifespan of a tankless water heater can also end up being quite a bit shorter than it normally would be if it isn’t flushed and descaled often enough.
High 5 Plumbing, Heating & Cooling has been providing expert plumbing and water heater services to the Denver Metro area since 2012. In just over a decade, we’ve earned a reputation as the most reliable, most trustworthy plumbing contractor in the area. Our dedication to excellence even earned us the 2022 Small Business of the Year award from the Denver Metro Chamber of Commerce. Our team of experienced, licensed plumbers specializes in water heater maintenance, repairs and installation as well as all other plumbing, gas line, sewer and drain services. If you need to schedule a water heater maintenance appointment or any other service, contact us today.