Water heaters are essential appliances that provide hot water for various household needs, from showers to dishwashing. They come in traditional and tankless designs, sizes, and fuel options, each with its own set of advantages. The key to selecting the right water heater is understanding your household’s hot water demands and balancing that with energy efficiency and budget considerations.
When choosing a water heater, it’s important to look beyond the up-front cost. Factors such as energy efficiency, fuel type, and maintenance requirements can significantly impact the long-term expenses and performance of your unit. Additionally, considering the installation space and local building codes is crucial for a successful setup.
Here are our picks for the top water heaters on the market.
Top 5 Water Heaters
- Stiebel Eltron Electric Tankless Water Heater: Best Overall
- Rinnai Gas Tankless Hot Water Heater: Best Gas Tankless Heater
- Bosch Electric Mini-Tank Water Heater: Best Point-of-Use Heater
- EcoSmart Electric Tankless Water Heater: Best Electric Tankless Heater
- GASLAND Portable Gas Water Heater: Best Portable Heater
Compare Top Water Heaters
| Product | Power Source | Tank Design | Capacity/Flow Rate | Warranty |
|---|---|---|---|---|
Stiebel Eltron Electric Tankless Water HeaterCheck Price | Electric | Tankless | 5 GPM | Heat exchanger: 7 years, Parts: 3 years |
Rinnai Gas Tankless Hot Water HeaterCheck Price | Gas | Tankless | 6.5 GPM | Heat exchanger: 10 years, Labor: 5 years, Parts: 1 year |
Bosch Electric Mini-Tank Water HeaterCheck Price | Electric | Tank | 4 gallons | Tank: 6 years, Parts: 2 years |
Stiebel Eltron Electric Tankless Water HeaterCheck Price | Electric | Electric | 6.5 GPM | Heat exchanger and parts: limited lifetime |
Stiebel Eltron Electric Tankless Water HeaterCheck Price | Gas | Tankless | 1.6 GPM | Not listed |
Best Overall
Stiebel Eltron Electric Tankless Water Heater
Pros and Cons of Stiebel Eltron Electric Tankless Water Heater
- Is outfitted with memory settings
- Provides silent operation
- Has an advanced flow control function that keeps water temperature consistent while it’s in use
- Has a hefty restocking fee
- Has a larger footprint than other electric models
What People Are Saying About The Stiebel Eltron Electric Tankless Water Heater
We found that customers liked the longevity and reliability of this hot water heater. They said it worked in their home for over 10 years and dramatically reduced their energy bills. Unsatisfied customers that we saw said that the unit arrived defective and others said it didn’t work properly on well water.
“This is an absolutely amazing water heater. I replaced my propane-tanked water heater with this. My dad and I installed it ourselves in about three hours, including running new electric to the water heater closet … On to performance. I was skeptical at first, having been told by a few plumbers that on-demand technology wasn’t up to par … I decided to give this one a shot. I have to say that not only am I impressed, but was also shocked and highly satisfied with this machine’s performance. It produces hot water on demand, limited only by your water supply.” — Andrew Switzer via Amazon
“These water heaters can’t seem to handle well water or water that has high dissolved solids. Even my softened water with phosphate treatment will cause these to start having issues pretty quickly. I also descale mine regularly per the manufacturer-recommended method, and even that doesn’t help. After a year or two, the unit will start tripping the No.1 Safety thermal cut out.” — Mike L via Amazon
Best Gas Tankless Heater
Rinnai Gas Tankless Hot Water Heater
Pros and Cons of Rinnai Gas Tankless Hot Water Heater
- Has a tankless design powered by natural gas
- Operates with a maximum flow rate of 7.5 GPM
- Comes with a 10-year heat exchanger warranty, five-year labor warranty, and one-year parts warranty
- The unit works harder than necessary if your local groundwater temperatures are colder than average
- The module for WiFi control isn’t included
What People Are Saying About The Rinnai Gas Tankless Hot Water Heater
Users were happy with this water heater’s efficient temperature control, high water pressure, and non-invasive design. The small selection of customers who left negative reviews struggled with installation, as it required an unusual venting system.
Best Point-of-Use Heater
Bosch Electric Mini-Tank Water Heater
Pros and Cons of Bosch Electric Mini-Tank Water Heater
- Has an electric design
- Holds up to 4 gallons of water
- Comes with a 6-year tank warranty and 2-year parts warranty
- Doesn’t have a digital temperature display
- Has a limited range compared to full-size water heaters
What People Are Saying About The Bosch Electric Mini-Tank Water Heater
Those who were pleased with this water heater mentioned its easy setup and affordable price. They also said that it heated water instantly and effectively. However, unhappy users wrote that the heater was prone to leaking.
Best Electric Tankless Heater
EcoSmart Electric Tankless Water Heater
Small but mighty, this electric tankless water heater takes up 12 cubic feet of space on your wall and warms up to 6.5 gallons of water per minute. Because it’s not constantly warming water in a tank, it can reduce your electricity costs by up to 50%.
Pros and Cons of EcoSmart Electric Tankless Water Heater
- Has an electric, tankless design
- Operates with a maximum flow rate of 6.5 GPM
- Comes with a lifetime warranty
- Some customers reported issues with warranty validation
- The warranty doesn’t extend to any applicable labor costs
What People Are Saying About The EcoSmart Electric Tankless Water Heater
Positive reviews said that this water heater lasted several years, heating a lot of water efficiently. When customers did have issues with longevity, they struggled to get the manufacturer to cover the repairs with the warranty.
Best Portable Heater
GASLAND Portable Gas Water Heater
Pros and Cons of GASLAND Portable Gas Water Heater
- Has a gas, tankless design
- Has water heater safety features, including dry combustion and low water flow detection
- Includes a detailed instruction manual and necessary hardware
- Although it can be used indoors, it’s primarily designed for outdoor use only
- Some customers said that the water didn’t get hot enough
What People Are Saying About The GASLAND Portable Gas Water Heater
Users who gave this portable water heater four- and five-star ratings said that the unit was lightweight, easy to install, and the controls were simple to operate. Conversely, some reviewers said that the unit was susceptible to freezing, despite its built-in anti-freezing protection.
Hot Water Heater Sizes
Even if you were happy with the old tank, don’t automatically assume it had a suitable heating capacity. To determine that capacity, you first need to add up how much hot water your household uses during the busiest hour of an average day.
“Size a water heater for your demand 363 days a year, not the one or two days that you’ve got 25 relatives visiting,” says Richard Trethewey, This Old House plumbing and heating expert. “Otherwise, you’ll end up with an energy-gobbling beast in the basement.”
This sum—your household’s “peak-hour demand” for hot water — should be close to your water heater’s “first-hour rating” (FHR) printed on each heater’s yellow Energy Guide label. The FHR tells you how many gallons of hot water a heater can produce during an hour of high usage. (It is not the same as the number of gallons a tank can hold.)
Assessing Water Heater Efficiency
The following number to look at is the energy factor (EF), representing the percentage of energy that is turned into hot water by that specific model. The higher the number, the more efficient the unit and the less it will cost to operate. (An EF of 1 would indicate that 100 percent of the energy a heater uses is converted into hot water—which is physically impossible.)
While a high EF is good, you have to factor in the cost of the energy the heater uses to get an accurate picture of how much it costs to operate. In most areas, for example, an electric heater with an EF of 0.8 will cost more to run than a similar-size gas model with an EF of 0.6 due to the higher price of electricity compared with gas.
In most cases, water heaters with high EFs cost more to buy, but don’t overlook the potential long-term savings in fuel costs. Here’s an easy formula to calculate the payback period when comparing heaters with the same FHR rating but different prices: Divide the difference between the prices of the two models by the difference between their estimated annual operating costs (printed on the Energy Guide labels). The result is the number of years it will take the energy savings to offset the higher purchase price. Look for a payback within 10 years, which is the expected lifespan of an average heater. Of course, if energy prices go up during that time, the payback period will be shorter.
Keep in mind that the estimated annual operating cost is just an approximation. To more accurately predict performance and payback time, plug each model’s EF and your actual energy cost into the online worksheets provided by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI).
Comparing Types of Hot Water Heaters
When comparing the different types of heaters, you’ll see that gas and oil-fired units generally have higher FHRs relative to their tank size than electric models. (Flames heat water more quickly than heating elements do.) If you come up with a high FHR on your worksheet, say 100 gallons or so, you may need to install a second water heater.
Storage Tank Water Heaters
Storage tank water heaters are the most common type found in homes. They consist of an insulated tank that holds and heats water until you need it. These units are available in various sizes and can be powered by electricity, natural gas, or oil.
Pros
- Lower up-front cost
- Simple installation
- Variety of sizes available
Cons
- Higher energy consumption due to standby heat loss
- Limited hot water supply based on tank size
Tankless Water Heaters
Tankless water heaters, also known as on-demand water heaters, heat water directly as it flows through the device. They don’t store hot water, which eliminates standby energy losses associated with storage tanks.
Pros
- Energy-efficient
- Endless supply of hot water
- Compact size
Cons
- Higher upfront cost
- May require upgrades to the home’s electrical system or gas line
Heat Pump Water Heaters
Heat pump water heaters use electricity to move heat from the air or ground to heat water, rather than generating heat directly. They can be two to three times more energy-efficient than conventional electric resistance water heaters.
Pros
- Highly energy-efficient
- Lower operating costs
Cons
- Higher up-front cost
- Require specific installation conditions (adequate space and air temperature)
Solar Water Heaters
Solar water heaters use the sun’s energy to heat water. They typically include a storage tank and solar collectors. These systems can be a great option in sunny climates and for those looking to reduce their carbon footprint.
Pros
- Very low operating costs
- Environmentally friendly
Cons
- High initial investment
- Dependent on climate and sun exposure
- May require a backup system for cloudy days
Comparing Water Heater Fuel Types
Electric Water Heaters
Electric water heaters are known for their high efficiency and quiet operation. They’re available in both tank and tankless models.
Pros
- High-efficiency ratings
- No venting required
- Can be installed almost anywhere
Cons
- Higher operating costs in most areas due to electricity prices
- Slower recovery rate compared to gas models
Gas Water Heaters
Gas water heaters, fueled by natural gas or propane, typically have lower operating costs than electric models in most regions.
Pros
- Lower operating costs in most areas
- Faster recovery rate
- Can operate during power outages
Cons
- Require proper venting
- Slightly lower efficiency than electric models
- Potential safety concerns with gas leaks
Oil-Fired Water Heaters
Oil-fired water heaters are less common but can be an option in areas where oil is a primary heating fuel.
Pros
- Heat water faster than electric or gas units
- Good option where natural gas isn’t available
Cons
- Higher operating costs due to oil prices
- Require more maintenance
- Less environmentally friendly
Water Heater Performance Features
After determining a heater’s size and efficiency rating, consider these other important factors that increase longevity and reduce operating costs.
Tank Material
The typical tank is “glass” lined steel (actually porcelain enamel). It contains magnesium or aluminum rods suspended in the tank to fight internal corrosion, which is the number-one reason water heaters fail early.
Stainless steel tanks don’t rust (and therefore don’t need anodes), but they’re more expensive than glass-lined tanks. Their higher cost may be worth it in areas where the water is highly corrosive (acidic) or reactive (full of minerals that encrust the tank walls, slowing heat transfer).
Insulation
Whether foam or fiberglass, the insulation surrounding a gas- or oil-fired tank should be R-16 or higher and R-22 or more for electric models. Insulation reduces standby losses — heat that escapes while the unit is idle. Wrapping your tank in a fiberglass blanket won’t make up for insufficient insulation built into the tank.
Heat Traps
These built-in devices — either valves or flexible connectors bent into an inverted U—put a stop to “thermosyphoning,” the tendency for hot water to rise up the supply pipe. If your water heater doesn’t have one built-in, a heat trap can be added during installation (or retrofitted to existing heaters).
Making Your Selection
Factor in warranties and the manufacturer’s reputation before making your purchase. There’s no single source to turn to for this information; talking to a few reputable plumbers and plumbing supply stores should help you narrow the choices. Also, when considering the price of installing a water heater, you may be able to take advantage of rebates or incentives offered by local utilities and municipalities to encourage the purchase of energy-efficient models. (Check the Database of State Incentives for state-by-state listings.) Finally, ensure the heater you’ve chosen will fit in the available space and leave enough room for servicing.
Once you’re ready to buy, your plumber should be able to order the model you want. Alternatively, you may be able to buy directly from a local home center. In either case, professional installation will take about one to three hours; be sure it includes the cost to remove and dispose of the old heater.
Water Heater Installation Considerations
There are two options for water heater installations: DIY and professional.
DIY Vs. Professional Installation
While some homeowners may be tempted to install a water heater themselves, professional installation is often the safer and more efficient choice. Professional installers can ensure proper venting, fuel line connections, and compliance with local building codes.
Space Requirements and Accessibility
Consider the physical space where your water heater will be installed. Ensure there’s enough room for the unit and any required clearances for maintenance. Proper ventilation is crucial for safety for gas and oil heaters.
Water Heater Maintenance Tips
Performing the following tasks annually or hiring a plumber or HVAC professional can help your water heater last as long as possible.
- Drain the tank until the water runs clear. If there’s a lot of sediment, drain the tank twice a year.
- Inspect the pressure relief valve for corrosion. If it is rusty, have a plumber replace it right away.
- Check the combustion chamber and flue vent for rust, corrosion, and obstructions on gas or oil-fired unit. On an electric heater, remove and check the heating elements, but shut off the power and drain the tank.
- Remove and inspect the anode rod (or rods). Replace if 6 inches of the rod’s core wire are exposed.
- Keep water temperature between 120 and 130 degrees. (Check with a thermometer under the tap.) Higher temperatures speed corrosion.
Water Heater FAQs
How much does a water heater cost?
Water heater pricing can start as low as $150 and reach as high as several thousand dollars, with units averaging between $400 and 600. This broad price range is due to water heaters’ varying capacities, features, and designs. Ultimately, your local water supply and heating needs should determine how much to spend on a quality unit.
How long do water heaters last?
On average, storage tank heaters last about 8 to 12 years, while tankless water heaters provide 20 years of hot water. However, despite water heater myths about lifespan, how well you maintain your water heater and how often you use it can play a role in its lifespan.
What are some signs of a failing water heater?
Here are some common signs that it’s time to repair or replace your water heater:
- Banging noise
- Pipe corrosion
- Discolored water
- Pooling water
- Water temperature drop
Our Methodology
To provide our readers with the best recommendations possible, we rely on several key sources of information to help guide our selection process.
Initial Research: Our research process began by generating a list of hot water heaters with a significant number of verified buyer reviews and an average customer review rating of 4–5 stars. We looked at both positive and negative reviews, focusing on information from both satisfied and critical buyers.
Expert Insights: Through our years of experience, we’ve learned that listening to what others have to say is key to building accurate, well-rounded articles. To complement our in-house expertise, our team looked at reviews and videos from trusted publications and independent testers, spoke with subject matter experts, and drew insights from reader contributions.
Final Product Selection: We then began fine-tuning our list by replacing older models with the latest versions and eliminating any discontinued models. From there, we pared the list down further by comparing each model’s feature set and selecting the best-in-class options for a variety of buyers, budgets, and scenarios.
Why Trust Us?
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Our team focuses on creating in-depth product and service review content. To date, we’ve published over 1,600 reviews on products in the home space, from doorbell cameras and backyard fencing to pool vacuums and snow blowers.
Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the right purchase.