Best Electric Tankless Water Heaters

Imagine waking up on a chilly morning, ready to jump into a warm shower, only to discover that your hot water tank has run dry. This scenario is all too familiar for many homeowners, and it highlights a common problem: traditional water heaters often struggle to keep up with demand. Fortunately, electric tankless water heaters offer a solution, providing hot water on demand without the limitations of a bulky storage tank.

When choosing the best electric tankless water heater, several factors come into play. Ideal options balance performance, energy efficiency, and installation requirements. The best models not only provide continuous hot water but also save on space and energy costs, making them a smart choice for modern households. A well-chosen unit can significantly enhance your comfort, whether you’re running multiple fixtures or just need hot water for specific tasks.

In this roundup, we’ve evaluated the market’s leading electric tankless water heaters. Our top picks include models from Rheem and NOVIEEX, each with unique features that cater to different needs. From high-capacity units suitable for larger families to compact options designed for small spaces, read on to find your perfect match.

Here’s a quick overview of our top selections:

Features	Rheem RTEX-24	Rheem 18kW	Rheem 11kW	110V Tankless Heater	NOVIEEX 18kW
Power	24kW	18kW	11kW	3000W	18kW
Flow Rate	Up to 5.9 GPM	Up to 4.4 GPM	Up to 2.68 GPM	0.3-0.5 GPM	Up to 4.9 GPM
Temperature Control	80°F – 140°F	80°F – 140°F	80°F – 140°F	82°F – 131°F	77°F – 140°F
Ideal for	Large families	Medium homes	Small apartments	Small spaces	Medium homes
Energy Efficiency	High	High	High	98%	99.8%

Rheem RTEX-24 24kW E…

The Rheem RTEX-24 is designed for large families or households with multiple hot water demands. With a flow rate of up to 5.9 GPM, this unit can keep up with several simultaneous uses like showers, dishwashing, and laundry without skipping a beat. Its performance makes it an ideal choice for homes requiring a steady supply of hot water.

This model stands out due to its high capacity and adjustable temperature controls. You can set the water temperature in 1-degree increments, ranging from 80°F to 140°F. Additionally, the requirement for 240V single-phase power and a robust electrical setup ensures this unit runs efficiently under demanding conditions.

One limitation is its installation complexity. The RTEX-24 requires a professional installation to meet its electrical demands, which may deter some users looking for a straightforward setup. It’s essential to consider your home’s electrical configuration before purchasing.

• Power: 24kW
• Flow Rate: Up to 5.9 GPM
• Temperature Range: 80°F – 140°F
• Electrical Requirements: 240V
• Best for: Large families

Rheem 18kW Tankless…

The Rheem 18kW model is perfect for medium-sized homes or apartments that need reliable hot water for about two to three fixtures simultaneously. With a flow rate of up to 4.4 GPM, it provides enough hot water for average daily use, making it suitable for families who want efficiency without excessive capacity.

This unit features advanced self-modulation technology, which adjusts the power input based on the hot water demand. This not only ensures optimal performance but also enhances energy efficiency, potentially reducing your utility bills. The external digital thermostatic control allows for easy temperature adjustments, leading to a user-friendly experience.

However, it may not be powerful enough for larger households with high simultaneous water use. If your family frequently runs multiple showers or appliances at once, this model might struggle to keep up.

• Power: 18kW
• Flow Rate: Up to 4.4 GPM
• Temperature Range: 80°F – 140°F
• Electrical Requirements: 240V
• Best for: Medium-sized homes

Rheem 11kW Multi Fixture…

The Rheem 11kW is an excellent choice for small apartments or homes with minimal hot water needs. Providing up to 2.68 GPM, it’s suitable for single-use scenarios, like running a shower or a sink tap. This model is perfect for individuals or couples who prioritize space and efficiency.

This water heater’s compact design and lower power requirements make it easier to install. You won’t need extensive electrical upgrades, making it a more accessible option for renters or those in smaller living spaces. The digital thermostatic controls ensure you have precise temperature settings, enhancing comfort.

However, it does have limitations in flow rate. This unit is not designed for simultaneous multiple uses, so if you anticipate higher demands, you might want to consider a more powerful model.

• Power: 11kW
• Flow Rate: Up to 2.68 GPM
• Temperature Range: 80°F – 140°F
• Electrical Requirements: 240V
• Best for: Small apartments

110V Tankless Water Heate…

This 110V tankless water heater is tailored for small spaces like kitchens, bathrooms, or RVs. With a capacity of 3000W, it raises water temperature quickly, making it suitable for point-of-use installations. The compact design and straightforward installation process are key selling points for those with limited space.

Safety features are abundant, including waterproof protection, automatic shut-off in case of overheating, and reliable leakage detection. This model’s efficiency is impressive, boasting a thermal efficiency of up to 98%, which can help lower energy costs over time.

On the downside, the flow rate of this unit is limited to 0.3-0.5 GPM, which makes it unsuitable for shower use. It’s best for tasks like washing hands or dishes, so consider your specific needs before opting for this model.

• Power: 3000W
• Flow Rate: 0.3-0.5 GPM
• Temperature Range: 82°F – 131°F
• Electrical Requirements: 110V
• Best for: Small spaces

18kW Tankless Water Heate…

The NOVIEEX 18kW tankless water heater is an ideal solution for medium homes needing hot water for two to three fixtures at once. Its flow rate of up to 4.9 GPM ensures that multiple hot water demands can be met simultaneously, accommodating families with busy schedules.

This model is distinguished by its high thermal efficiency of 99.8%, meaning it only heats water when needed, eliminating standby energy waste. The adjustable temperature settings from 77°F to 140°F allow for precise control, ensuring comfort without the risk of scalding.

However, installation requires attention to electrical specifications, including the need for a qualified electrician to ensure compatibility with your home’s wiring. While it performs well, the upfront installation could be a consideration for budget-conscious buyers.

• Power: 18kW
• Flow Rate: Up to 4.9 GPM
• Temperature Range: 77°F – 140°F
• Electrical Requirements: 240V
• Best for: Medium homes

How We Chose These Products

To compile this list, we focused on performance, energy efficiency, and real-world user feedback. Each product was evaluated based on flow rate, temperature control capabilities, and suitability for different household sizes. Our goal was to highlight models that cater to a variety of needs, ensuring there’s an option for every buyer.

We also considered installation requirements and safety features, recognizing that some buyers may prefer easier setups or additional protections. Overall, our selections aim to provide reliable hot water solutions for diverse living situations.

Buying Guide: What Really Matters

When shopping for an electric tankless water heater, consider your household hot water needs first. Analyze the number of fixtures you typically use simultaneously to determine the required flow rate. Also, evaluate your home’s electrical system and whether it can support the power requirements of higher-capacity units.

Energy efficiency is another crucial element. Selecting models with high thermal efficiency ratings can significantly reduce utility costs over time. Additionally, look for features like digital controls for precise temperature settings, ensuring comfort and safety.

Our Top Recommendation

The Rheem RTEX-24 stands out as the best overall choice, thanks to its high flow rate and robust performance for larger households. For those with medium-sized homes or lower hot water demands, the Rheem 18kW offers a solid balance of power and efficiency. The 110V model is perfect for those in need of compact solutions, while the NOVIEEX 18kW excels in efficiency for medium homes.

Frequently Asked Questions

1. How do I choose the right size tankless water heater?
Select based on your hot water needs. Calculate the flow rate needed for simultaneous use in your home.

2. Can I install a tankless water heater myself?
While some models allow DIY installation, many require professional installation for optimal performance and safety.

3. What is the lifespan of an electric tankless water heater?
Typically, these units last around 20 years with proper maintenance, which is longer than traditional tank water heaters.

4. Do tankless water heaters save energy?
Yes, they only heat water on demand, reducing energy waste compared to traditional heaters that continuously heat water.