Your water heater works quietly in the background providing hot water for showers, dishes, and laundry, and until there’s an issue, it’s easy to take it for granted. If you recently saw a rise in your electric bill or your water heater has started making strange noises, you may wonder, “How long do water heaters last?”
Types of Water Heaters and Their Life Expectancies
There are several types of water heaters, and their life expectancies vary depending on various factors. From tankless water heaters to traditional ones, learn what influences the average life of a water heater.
Tankless Water Heaters
Often selected for their efficiency, tankless water heaters provide hot water at the point of use. They can be single-point or whole-house systems, and as their name implies, there’s no tank so you don’t have to worry about problems like tank corrosion.
Lifespan and Maintenance
Tankless water heaters have a lifespan of about 15 to 25 years, requiring little maintenance beyond visual inspections, cleaning inlet filters, and replacing blown fuses. Annual service by qualified professionals will ensure their longevity.
Conventional Tank Water Heaters
Traditional water heaters usually run on electricity, natural gas, or propane. They are centrally located in a home to supply hot water needs for the whole house. They are less efficient than tankless options because they keep a tank of water hot all the time.
Lifespan and Maintenance
Conventional tank water heaters last about 8 to 12 years, depending on several factors. Water quality and maintenance are the two most significant factors determining how long a conventional water heater lasts. You should flush them once or twice a year, and if the unit malfunctions, you may need to replace the heating element.
Heat Pump Water Heaters
Heat pump technology is gaining popularity. It’s used to heat water and homes, relying on refrigeration technology to transfer heat from the air or ground. Heat pumps are more energy-efficient than traditional electric water heaters.
Lifespan and Maintenance
Since heat pump water heaters don’t supply hot water on demand, they need a tank. Like traditional tank water heaters, you should drain and flush them once or twice a year. They typically last about 10 to 15 years.
Solar Water Heaters
Solar domestic hot water systems use the heat from the sun to provide your home with hot water. They cost more to install but offer significant savings over other water heaters.
Lifespan and Maintenance
Solar water heaters last about 20 years, usually 10 to 25 years, so the replacement costs are lower than traditional models. Water heater life expectancy depends on the quality of installation and how well they are maintained.
Routine maintenance of solar water heaters includes periodic cleaning and inspection of the thermal collectors. You must also check storage systems for leaks and flush them regularly.
Signs That You Need to Replace a Water Heater
Old water heaters cost more to operate, but since replacement costs are high, you want to get as much life as possible out of them. Understanding the average lifespan of a water heater is the first step, but you also need to recognize the signs to tell when it’s time to replace your water heater.
Rust and Corrosion
One of the most common problems with water heaters is rust and corrosion. It’s often noticeable because the water is discolored, and it’s usually caused by one of the following issues:
- Sediment buildup
- Damaged anode rods inside the tank
- Corrosion in the pipes
- Bacteria growth inside the tank
- Deteriorated walls in the tank liner
Rust and corrosion may also be visibly noticeable on the outside of the tank.
Inconsistent Temperature
Fluctuating temperatures are another common problem with failing electric water heaters. A bad heating element is the usual cause of inconsistent water temperature.
Traditional electric units have two elements. Typically, there is one on the top and one on the bottom. Either one can go out, causing inconsistent water temperatures.
Strange Noises
Normally, water heaters operate quietly, and you hardly notice their presence. If your water heater starts hissing, squawking, or rumbling, it’s a sure sign that something is wrong.
| Strange water heater noise | Probable causes | Solution |
| Banging and rumbling | Sediment buildup; Water hammer | Drain and flush the tank |
| Persistent crackling and hissing | Heating element obstruction; Sediment buildup | Drain and flush the tank, replace the heating element |
| Ticking | Change in water pressure | Adjust pressure-reducing valve |
| Screeching and whistling | Loose valves, including inlet, outlet, and pressure-relief valves | Check all valves |
| Popping | Sediment buildup; Alkali deposits react with the element | Drain and flush the tank |
You may need to contact a repair technician if any of the solutions aren’t successful or if you can’t do them on your own.
Leaks and Moisture
Water heaters are designed as closed systems. If you notice any leaking around seams, seals, valves, and connections, it’s a sign that you need to replace it.
Sometimes, condensation is responsible for water on the outside of the tank. While it can be normal, water condensation is problematic if it causes corrosion or leads to pilot light outages.
You can determine the difference between a water heater leak and condensation by wiping up all moisture and checking for persistent moisture and pooling.
Reduced Hot Water Supply
Another sign that your water heater needs to be replaced is if it suddenly stops producing enough hot water. This problem is most common with electric tank water heaters, usually due to sediment buildup caused by inadequate maintenance.
Discolored or Foul-Smelling Water
Discolored or metallic smells and tastes are a sign that your water heater is failing. Foul-smelling water is usually caused by tank sediment buildup or bacterial infections. If it’s bacteria, the water is likely unsafe for use, and your tank should be replaced.
Fluctuating Water Pressure
If you notice a significant difference in the amount of water pressure between your cold water faucet and the hot one, it’s a sign there’s something wrong with your water heater. Sediment buildup is the most common reason, and flushing or draining your tank may be a solution.
Lack of Efficiency
The easiest way to tell a water heater is failing is if your energy bills increase unexpectedly. When water heaters are at the end of their lifespan, they don’t operate as efficiently, so it takes more energy to heat the water.
Tips for Replacing Water Heaters
Follow these tips and tricks when replacing your water heater.
Proper Sizing for Your Needs
Sizing a new water heater is an important step in ensuring successful water heater replacement. Consider factors like how many people are in your household, the number of fixtures, and peak water consumption times to determine usage patterns.
| Water heater type | Factor to consider | Size |
| Conventional tank | 1-2 occupants | 30-gallon tank |
| 2-4 occupants | 40-gallon tank | |
| 5 or more occupants | 50-gallon tank | |
| Tankless | 1-2 fixtures running simultaneously | 3.5 gallons per minute (gpm) |
| 2-3 fixtures running simultaneously | 5 gpm | |
| 3-4 fixtures running simultaneously | 7 gpm | |
| Solar water heater | 1-2 people | 20 square feet of collection space |
| Each additional person | Add 12 to 14 square feet of collector area |
Energy Efficiency Ratings
Water heaters are rated based on their energy efficiency so that consumers can make informed purchasing decisions. The primary rating system is the UEF, or Uniform Energy Factor, determined by the Department of Energy’s testing method. The higher the UEF rating, the more efficient it is.
Solar models are rated by how much energy the system delivers divided by the backup energy required. For certification, the Solar Uniform Energy Factor (SUEF) must be greater than or equal to 3.00 for electric backup and 1.8 for gas backup.
Choosing the Right Fuel Source
The availability of fuel sources in your area will help you choose the right fuel source. Here are the most common types of fuel sources for heating water.
| Water heater fuel options | Availability | Suitable water heater types |
| Natural gas | Widely available in areas with natural gas infrastructure | Tank, tankless, and backup heat source |
| Propane | Available, requires a tank | Tank, tankless, and backup heat source |
| Electricity | Universally available | Tank, tankless, and backup heat source |
| Solar | Universally available, more abundant in the Southwest | Solar water heaters |
| Heat pump | Universally available | Heat pump water heaters |
Installation Location
If you’re simply swapping out your old water heater tank with a new one, installation is pretty straightforward. Other factors, including ventilation, plumbing, accessibility, and space requirements, must be considered if you’re installing a new type.
In some areas, the labor costs are higher, which can also impact the cost of replacing a water heater.
Routine Maintenance for Water Heaters
All water heaters require routine maintenance. The type and frequency of maintenance varies depending on the fuel source, water quality, and whether you have a tank or tankless water heating system.
Additional Considerations When Gauging How Long Water Heaters Last
Some water heaters are good for longer than others. Even if yours isn’t the longest-lasting water heater, it can still last up to 20 years if it’s properly cared for.
Manufacturer’s Warranty
The average manufacturer’s warranty on a water heater is 6 to 12 years. Even though some manufacturers offer extended warranties, they may not cover all your costs associated with repairs and replacements.
Water heater warranties can be confusing, and user error, improper maintenance, and DIY installation can void the warranty. Always adhere to maintenance and installation guidelines to maximize the benefits of your water heater’s warranty.
Local Water Quality
Your local water quality greatly impacts your water heater’s useful life. Hard, alkaline water is more likely to cause sediment buildup and mineral deposits that shorten the age of a water heater. If you have hard water, consider water softening and filtration solutions to mitigate these problems.
Climate and Environmental Factors
Climate and energy-conscious homeowners should consider the following facts:
- Water heaters account for 20% of household energy usage.
- Electric models are more efficient than gas.
- Tankless-style water heaters are the most environmentally friendly.
- Eco-friendly options like solar and geothermal water heaters are available.
If it’s time to replace your water heater, try to see it as an opportunity to make your home more energy-efficient.
DIY Water Heater Replacement vs. Professional Installation
There are significant disadvantages to DIY water heater installation, and it’s not typically recommended. If you’re considering a DIY installation, carefully calculate the risks based on your skill level, local regulations, permit requirements, and safety concerns.
Professional installation of water heaters ensures compliance and warranty coverage. While you can save money with DIY water heater replacement, it may not be worth it.
5 FAQs About Hot Water Heater Lifespans
Are the lifespans of gas water heaters and electric water heaters different?
Electric water heaters usually last longer than gas water heaters, but their life expectancies depend on a variety of factors, including water quality and how well they’re maintained. Gas water heaters typically last about 8 to 12 years, while electric water heaters last 10 to 15.
Can you extend the life of water heaters with maintenance?
The best way to extend the lifespan of your water heater is to maintain it properly. Different water heaters require various types of maintenance to be performed.
Can a water heater last 20 years?
Many types of water heaters last longer than 15 years. Solar water heaters generally last 20 years or more.
While conventional tank water heaters usually only last 10 to 15 years, the larger they are, the longer they’ll last, so 50-gallon tanks usually last longer than 40-gallon ones. Regular maintenance also increases life expectancy.
Is it more cost-effective to repair or replace an old water heater?
In the long run, replacing a water heater is often more cost-effective than repairing it, especially if it’s near the end of its lifespan. Water heaters become less efficient as they age, and the increased operational costs can offset any savings you’ll see by repairing rather than replacing them.
Are there any eco-friendly options for water heater replacement?
Eco-friendly options for water heaters include using ENERGY STAR appliances or opting for an alternative energy source, such as solar or geothermal heat.
