If you’re looking for the best electric tankless water heaters in 2025, I recommend models like Rheem RTEX-24, EcoSmart ECO 11, and Stiebel Eltron Tempra 24 Plus, which combine advanced self-modulating technology, precise temperature control, and high efficiency. These units deliver instant hot water while saving space and energy. Whether for small households or point-of-use needs, selecting the right unit depends on your flow demands and electrical setup. Keep exploring—I’ll share more helpful insights with you next.
Key Takeaways
- Top models offer rapid hot water delivery with advanced flow control and digital thermostats for precise temperature management.
- High-capacity units support multiple fixtures, ideal for whole-home use or larger households.
- Energy-efficient designs with self-modulating technology and high thermal efficiency reduce electricity costs.
- Compact, wall-mounted designs simplify installation and fit into tight indoor spaces without venting.
- Most units operate at standard 240V power, requiring professional electrical setup for safe, reliable operation.
Rheem 18kW 240V Tankless Electric Water Heater, Gray
If you’re looking for a reliable, energy-efficient electric tankless water heater, the Rheem 18kW 240V model is an excellent choice. It features durable copper immersion heating elements that are field serviceable, ensuring long-lasting performance. With a flow rate of up to 4.4 GPM, it provides sufficient hot water for most applications. The external digital thermostat with an LED display offers ±1 degree accuracy, giving you precise temperature control. Its self-modulation technology adjusts power efficiently based on demand. Easy to install, it connects via bottom 3/4 inch NPT water fittings, making replacement straightforward. This heater combines efficiency, control, and simplicity for reliable hot water.
Best For: homeowners or small commercial users seeking an energy-efficient, reliable electric tankless water heater with precise temperature control.
Pros:
- Durable copper immersion heating elements that are field serviceable for long-term use
- External digital thermostat with LED display for accurate ±1 degree temperature regulation
- Self-modulation technology ensures efficient power use based on hot water demand
Cons:
- Limited flow rate of up to 4.4 GPM may not suit larger households or high-demand scenarios
- Requires proper electrical wiring and installation experience due to 240V and power specifications
- May need additional space for installation and maintenance access
Rheem RTEX-24 24kW 240V Electric Tankless Water Heater, Gray
The Rheem RTEX-24 24kW 240V electric tankless water heater is an excellent choice for homeowners who need a reliable, space-saving solution to provide continuous hot water throughout their entire home. It’s suitable for various locations and delivers consistent hot water based on groundwater temperature. The unit requires a 200 AMP household service and three 40 AMP double pole breakers, so ensure your home can handle the power demand. With an easy-to-use ON/OFF dial and digital temperature display adjustable from 80 to 140°F, it’s energy-efficient, cost-effective, and simple to install—no venting needed. It’s a great choice for those seeking efficiency and convenience.
Best For: homeowners seeking a space-saving, energy-efficient, and reliable solution for providing continuous hot water throughout their entire home.
Pros:
- Compact, space-saving design that fits easily into various installation spaces
- Digital temperature control with precise adjustments from 80 to 140°F
- No venting required, simplifying installation and reducing setup costs
Cons:
- Requires a 200 AMP household electrical service and three 40 AMP double pole breakers, which may necessitate electrical upgrades
- Performance varies depending on groundwater temperature and flow rate
- Higher initial cost compared to traditional tank water heaters
EcoSmart ECO 11 Electric Tankless Water Heater
For those seeking an energy-efficient and space-saving solution for small-scale hot water needs, the EcoSmart ECO 11 Electric Tankless Water Heater stands out. It delivers consistent hot water within 1 degree of the set temperature, thanks to digital controls and patented self-modulating technology. Its compact design measures just 11.5 x 8 x 3.75 inches, making it perfect for wall mounting or point-of-use installation. Operating at 240 volts with a 54A draw, it provides a maximum flow rate of 3.1 GPM. With 99.8% thermal efficiency, it heats water only when needed, reducing energy consumption and standby heat loss.
Best For: individuals or small households seeking an energy-efficient, space-saving water heating solution for single or low-flow applications in moderate climates.
Pros:
- Compact size allows for easy wall mounting and point-of-use installation.
- High thermal efficiency of 99.8% reduces energy consumption.
- Digital controls provide precise temperature adjustment within 1°F.
Cons:
- Limited flow rate of 3.1 GPM may not support multiple fixtures simultaneously.
- Suitable primarily for climates with incoming water temperatures of 67°F and above.
- Requires a dedicated 240V electrical circuit with a 54A draw, which may need electrical upgrades.
14kW Electric Tankless Water Heater ORBEK (On Demand Hot Water Heater)
When space-saving and energy-efficient hot water solutions are priorities, the ORBEK 14kW electric tankless water heater stands out as an excellent choice. It operates at 240V with a 60AMP breaker, providing up to 3.38 GPM of instant hot water, ideal for 2-3 points of use. Its compact design fits easily into tight spaces, saving over 50% compared to traditional tanks. The heater heats water within 3 seconds, maintains a consistent temperature, and reduces electricity costs by up to 60%. Certified safe with features like leakage and over-temperature protection, it also offers easy control via a digital LED display.
Best For: homeowners or small businesses seeking space-saving, energy-efficient instant hot water solutions for multiple points of use.
Pros:
- Compact design saves over 50% space compared to traditional tank heaters.
- Delivers hot water within 3 seconds with stable temperature control.
- High energy efficiency can reduce electricity costs by up to 60%.
Cons:
- Requires a specific electrical setup (240V, 60AMP breaker, 6 AWG wires) which may need professional installation.
- Suitable for only 2-3 points of use simultaneously; not ideal for large households.
- Limited to a maximum flow rate of 3.38 GPM, which may not meet higher demand scenarios.
Stiebel Eltron Tempra 24 Plus Tankless Water Heater
If you’re looking for a compact, energy-efficient solution to provide continuous hot water for small to medium households, the Stiebel Eltron Tempra 24 Plus is an excellent choice. This sleek, wall-mounted unit offers advanced flow control technology that keeps water temperature steady, even during high demand, while reducing flow when necessary. It features a digital display, preset temperature, and memory buttons for easy adjustments. Its solid copper heating system ensures reliability, and self-modulating technology helps save energy—up to 34%. With a maximum temperature of 140°F and a compact design, it’s perfect for homes in warm or cooler climates, delivering consistent hot water without venting or noise.
Best For: small to medium households seeking an energy-efficient, space-saving water heating solution with reliable, continuous hot water.
Pros:
- Advanced flow control technology maintains consistent water temperature during high demand.
- Compact, sleek design saves space and requires no venting.
- Energy-efficient self-modulating system reduces electricity usage by up to 34%.
Cons:
- Requires a minimum electric service of 150A, which may necessitate electrical upgrades in some homes.
- Suitable for up to 2 showers in warm climates or 1-1.5 in cooler climates, limiting capacity for larger households.
- Fixed maximum temperature of 140°F may require adjustments for specific needs or safety considerations.
18kW Tankless Electric Water Heater, ORBEK Instant On-Demand Hot Water Supply, 240V
The ORBEK 18kW tankless electric water heater is an excellent choice for households seeking instant, reliable hot water without taking up much space. It operates at 240V and offers a flow rate of up to 4.17 GPM, enough for 2-3 fixtures simultaneously. Its compact size (17H x 13L x 3.9W inches) makes installation easy in tight spaces. It delivers hot water within 3 seconds, maintaining a stable temperature with advanced digital control. Designed for efficiency, it can cut electricity bills by up to 60%. Safety features like leakage protection and over-temperature safeguards assure reliable operation, making it a smart, space-saving solution for modern homes.
Best For: households needing an energy-efficient, space-saving solution for instant hot water supply for 2-3 fixtures simultaneously.
Pros:
- Provides instant hot water within 3 seconds with stable temperature control.
- Compact design easily fits into tight indoor spaces, saving over 50% of space compared to traditional heaters.
- High energy efficiency can reduce electricity costs by up to 60%, lowering utility bills.
Cons:
- Requires specific electrical setup (2 x 240V/40A breakers and 8 AWG wiring), potentially complicating installation.
- Flow rate limited to 4.17 GPM, which may not suffice for larger households or simultaneous high-demand fixtures.
- Installation may require professional assistance to ensure proper electrical and water connections.
Stiebel Eltron Tankless Water Heater – Tempra 29 Plus
The Stiebel Eltron Tempra 29 Plus proves to be an excellent choice for households seeking reliable, continuous hot water without the convenience of a bulky tank. Its German engineering ensures 99% efficiency, saving up to 34% on energy costs. With a sleek, space-saving design and no venting needed, it’s easy to install on a wall. The unit maintains consistent temperatures during high demand thanks to self-modulating technology. Suitable for up to three showers in warm climates or 2-3 bathrooms in cooler areas, it delivers steady hot water for showers, laundry, and dishes with minimal fuss.
Best For: households seeking an energy-efficient, space-saving tankless water heater capable of providing continuous hot water for multiple bathrooms or showers in various climates.
Pros:
- High efficiency of 99%, reducing energy costs by up to 34%
- Compact, space-saving design with no venting required for easy installation
- Maintains consistent water temperature during peak demand thanks to German self-modulating technology
Cons:
- Requires dedicated 40A electrical breakers and specific wiring, potentially complicating installation
- Limited flow rate of 3 GPM may not suffice for larger households with higher hot water demands
- Heavier and slightly larger than some compact models, requiring wall mounting considerations
Electric Tankless Water Heater WINTEMP 27kW 240V
Designed for households that demand instant, continuous hot water, the WINTEMP 27kW 240V electric tankless water heater stands out with its powerful 27-kilowatt capacity. It provides whole-house hot water flow up to 6.3 GPM and features a compact wall-mounted design measuring 11.1” x 19.1” x 4”. With LED temperature display, WiFi control, and ETL certification, it combines convenience with safety. Its self-regulating technology guarantees energy efficiency by adjusting power based on flow and temperature. Ideal for 2–4 usage points, it’s a space-saving, reliable solution that eliminates preheating wait times and delivers endless hot water whenever you need it.
Best For: households requiring instant, continuous hot water with space-saving installation and energy efficiency, especially suitable for 2–4 usage points.
Pros:
- Provides whole-house hot water flow up to 6.3 GPM with no preheating delay
- Compact wall-mounted design saves space and fits into tight areas
- Self-regulating technology reduces energy consumption by up to 99% and includes safety features like leak, overheat, and dry-fire protections
Cons:
- Requires specialized installation with 3 x 40 Amp double-pole breakers and appropriate wiring, which may need professional help
- Max temperature of 140°F may not be suitable for all hot water needs without additional mixing
- Higher initial cost compared to traditional tank heaters could be a consideration for budget-conscious buyers
Rheem 11kW 240V Tankless Electric Water Heater
If you’re looking for an efficient point-of-use water heater that fits tight spaces, the Rheem 11kW 240V Tankless Electric Water Heater is an excellent choice. It delivers continuous hot water with a flow rate up to 2.68 GPM, perfect for single fixtures or small applications. Its compact stainless steel design measures just 8.25 by 12.63 inches and mounts easily on the wall. Features like digital temperature control, LED display, and self-modulating power ensure energy efficiency and ease of use. No venting is needed, and it operates smoothly at up to 150 PSI, making it ideal for indoor, space-conscious setups.
Best For: individuals or small households seeking a space-saving, energy-efficient point-of-use water heater for indoor applications.
Pros:
- Compact size and wall-mounted design save valuable space.
- High energy efficiency with 99.8% performance, reducing utility costs.
- Easy digital controls and LED display for precise temperature management.
Cons:
- Limited flow rate of up to 2.68 GPM may not suffice for multiple fixtures simultaneously.
- Professional installation required due to electrical and plumbing connections.
- Suitable primarily for small-scale or single-point applications, not large households.
Westinghouse 14kW Smart WiFi Tankless Water Heater
For those seeking a compact and highly controllable electric tankless water heater, the Westinghouse 14kW Smart WiFi model stands out as an excellent choice. It provides continuous hot water up to 140°F, supporting a flow rate of 3.38 GPM—perfect for a shower and sink simultaneously. Its space-saving design (14.2” H x 9.5” W x 3.5” D) makes wall mounting easy, while smart features like app and voice control via Alexa or Google Home add convenience. With real-time LED status updates, four safety protections, and durable construction, it’s built for long-term use in apartments, homes, or offices. Plus, it’s ETL certified, ensuring safety and reliability.
Best For: individuals or families seeking a compact, smart-controlled electric tankless water heater capable of providing continuous hot water for multiple fixtures simultaneously.
Pros:
- Supports remote control and voice commands via app, Alexa, and Google Home for enhanced convenience.
- Compact, space-saving design with easy wall mounting suitable for various settings.
- Equipped with multiple safety features and durable construction, ensuring long-term reliability.
Cons:
- Limited to a flow rate of 3.38 GPM, which may not meet higher demand scenarios.
- Requires installation on a 60 AMP breaker with 6 AWG wiring, which might need professional setup.
- First available in July 2025, so may not be accessible for immediate purchase.
14kW Tankless Water Heater Electric (SIVUATEK 240V)
The SIVUATEK 14kW 240V tankless water heater stands out as an excellent choice for households needing reliable, instant hot water at multiple points of use. Its compact size (15.87×11.14×2.87 inches) makes it ideal for tight spaces, and it’s designed to serve 1-2 locations simultaneously, like a kitchen and bathroom. With a 60-amp circuit, it offers high heating power and up to 99% efficiency. Easy to install without disassembly, it features a smart LED display for precise temperature control from 86°F to 131°F. Built-in safety features ensure reliable, safe operation for consistent hot water whenever you need it.
Best For: households needing reliable, space-saving instant hot water for 1-2 points of use such as kitchens and bathrooms.
Pros:
- Compact size and flexible mounting options ideal for tight spaces
- High efficiency with up to 99% thermal efficiency and energy savings of up to 60%
- Easy installation with no disassembly required and precise temperature control via LED display
Cons:
- Requires a dedicated 60-amp circuit breaker, which may need electrical upgrades
- Suitable for only 1-2 points of use, limiting multi-room applications
- Does not include additional accessories or mounting hardware in the package
27kW Tankless Water Heater Electric with LED Display and Memory Function
A 27kW electric tankless water heater with an LED display and memory function stands out as an ideal choice for households seeking precise temperature control and energy efficiency. It provides continuous hot water for up to 6.5 GPM, suitable for multiple simultaneous uses like showers and appliances. The LED display allows me to set the temperature accurately between 86°F and 140°F in 1°F increments. Its memory function remembers my preferred settings after power cycles, while self-modulating technology optimizes energy use. Compact and efficient, this heater saves space and reduces energy costs, making it a smart, reliable solution for whole-home hot water needs.
Best For: households and small commercial settings seeking precise temperature control, energy efficiency, and reliable on-demand hot water for multiple simultaneous uses.
Pros:
- Delivers continuous hot water up to 6.5 GPM, suitable for multiple outlets at once
- LED display with adjustable temperature from 86°F to 140°F for precise control
- High thermal efficiency of 99.8% reduces energy costs and standby loss
Cons:
- Requires three 40A breakers and compatible 240V power supply for installation
- Compact size may limit installation options in certain spaces
- Initial setup and wiring may require professional assistance for safety and proper operation
Titan Electric Tankless Water Heater
If you’re looking for an energy-efficient solution to hot water needs, the Titan Electric Tankless Water Heater N-120 stands out with its impressive 99.5% efficiency. This compact, wall-mounted unit operates at 220 V and 54 amps, delivering fast, on-demand hot water with dual heating chambers. Its sleek white design fits seamlessly into indoor spaces, saving room while providing reliable performance. With a wattage of around 11,800 watts, it’s suitable for various residential applications. Customers praise its quick hot water delivery, durability, and energy savings, making it a popular choice among modern homeowners seeking efficient, instant hot water.
Best For: homeowners and residential users seeking an energy-efficient, space-saving, and reliable hot water solution with quick on-demand heating.
Pros:
- High energy efficiency at 99.5%, reducing electricity costs
- Compact wall-mounted design saves indoor space
- Dual heating chambers ensure faster hot water delivery
Cons:
- Requires a 220 V power supply and high current (54 amps), which may need electrical upgrades
- Limited to indoor installation; not suitable for outdoor use
- May have a higher initial cost compared to traditional tank systems
Rheem 8kW 240V Tankless Electric Water Heater
For anyone seeking a compact and reliable point-of-use water heater, the Rheem RTEX-08 8kW 240V model stands out as an excellent choice. It delivers instant hot water at up to 1.95 GPM, perfect for small spaces or single fixtures. The unit features an easy-to-use ON/OFF dial, an adjustable digital temperature display, and self-modulating power control for efficiency. Its stainless steel finish ensures durability, while wall-mounted installation saves space. Weighing just over six pounds, it’s lightweight and straightforward to install. With a max pressure of 150 PSI and a 30-day return policy, it’s an ideal solution for reliable, on-demand hot water.
Best For: individuals or small households seeking a compact, energy-efficient point-of-use water heater for reliable instant hot water.
Pros:
- Compact size ideal for small spaces and easy installation
- Digital temperature control and self-modulating power for efficiency
- Durable stainless steel finish and wall-mount design
Cons:
- Limited flow rate of up to 1.95 GPM may not suffice for multiple fixtures simultaneously
- Only suitable for indoor, point-of-use applications
- May require professional installation due to electrical and plumbing connections
Ranein 13kW Tankless Electric Water Heater
The Ranein 13kW Tankless Electric Water Heater is an excellent choice for small households or anyone needing instant hot water at 1-2 points of use. It delivers reliable, endless hot water with 240V power and a flow rate of up to 3.1 GPM, perfect for showers or sinks. Its compact design measures just 10.7″ x 7.9″ x 2.8″ and mounts easily on the wall. Features like an LED smart temperature display, constant temperature control, and safety protections—overheat, leak detection, and water-electrical separation—make it both efficient and safe. With up to 99% efficiency, it’s ideal for space-saving, energy-conscious applications.
Best For: small households or individuals needing instant, reliable hot water at 1-2 points of use with space-saving and energy-efficient solutions.
Pros:
- Compact, wall-mountable design fits easily in tight spaces
- Instant hot water with no preheating required for convenience
- Advanced safety features including overheat and leak protection
Cons:
- Suitable for only 1-2 water points, not ideal for larger households
- Flow rate limited to 3.1 GPM, may not meet high demand scenarios
- Requires 240V power, which may need electrical upgrades in some installations
Factors to Consider When Choosing Electric Tankless Water Heaters
When selecting an electric tankless water heater, I consider several key factors to guarantee it meets my needs. Things like power requirements, flow rate capacity, space for installation, temperature control, and energy efficiency all play a role. Evaluating these points helps me find a unit that’s both effective and practical for my home.
Power Requirements
Choosing the right electric tankless water heater depends heavily on your home’s electrical capacity and the unit’s power requirements. First, verify that your electrical system can support the heater’s voltage and amperage needs, typically 240V with circuits rated at 40A, 50A, or 60A. Confirm your household’s total electrical service, often 200A or more, can handle the added load without overloading. Match the heater’s wattage, which can range from around 8kW to over 30kW, with your circuit breaker size to avoid tripping or hazards. Remember, higher power units may need dedicated circuits or electrical upgrades, which can increase installation complexity and cost. Properly evaluating these factors ensures safe operation and reliable hot water supply.
Flow Rate Capacity
Flow rate capacity directly impacts how well your electric tankless water heater can serve multiple fixtures or appliances at once. It’s typically measured in gallons per minute (GPM), and a higher GPM rating means your heater can support more simultaneous hot water outlets. For larger households or homes with multiple points of use, choosing a unit with a higher flow rate is essential to prevent temperature drops. In colder climates, groundwater temperatures are lower, so you might need a higher flow rate to compensate. It’s important to match the flow rate capacity to your household’s hot water demand—overestimating can lead to unnecessary energy use, while underestimating could leave you without enough hot water when needed. Proper sizing ensures reliable performance and comfort.
Space & Installation
Selecting the right electric tankless water heater involves carefully considering the space where you plan to install it. Measure the available area to verify the unit fits comfortably and allows for proper ventilation if needed. Check your electrical system’s capacity to support the heater’s requirements, usually 240V and 40 amps, to avoid overloads. Many models are compact and wall-mounted, making them ideal for tight spaces or point-of-use setups. Make sure there’s easy access to water connections, typically 1/2 or 3/4 inch NPT fittings, for straightforward installation and maintenance. Also, consider the heater’s proximity to water fixtures; staying close minimizes pipe length and heat loss, which improves efficiency and flow rate. Proper planning ensures smooth installation and peak performance.
Temperature Control
When it comes to guaranteeing your electric tankless water heater meets your needs, precise temperature control makes all the difference. Accurate temperature regulation, usually via digital thermostats with ±1°F precision, ensures safety and comfort. Many units feature self-modulating technology that automatically adjusts power to keep water temperature steady, preventing fluctuations. The ability to set and preset desired temperatures in 1°F increments allows for personalized hot water settings, whether for bathing or cooking. External digital displays provide real-time temperature monitoring, making adjustments straightforward. Proper temperature control not only prevents scalding risks but also helps reduce energy waste by avoiding unnecessary heating. Overall, reliable and precise temperature management is essential for a safe, efficient, and customized hot water experience.
Energy Efficiency
Energy efficiency is a key factor to contemplate because it directly affects both your utility bills and environmental impact. Higher efficiency models, often exceeding 99%, minimize electricity use by heating water on demand, eliminating standby heat loss common in traditional tank heaters. Many models feature self-modulating technology that adjusts power based on hot water demand, preventing waste and optimizing energy use. Proper sizing and flow rate capacity are essential to ensure you get enough hot water without sacrificing efficiency. Look for certifications like ENERGY STAR, which indicate models meeting strict efficiency standards and guaranteeing cost-effective, eco-friendly operation. Choosing an efficient electric tankless water heater not only saves you money but also helps reduce your carbon footprint, making it a smart investment for both your home and the environment.
Frequently Asked Questions
How Do I Troubleshoot Common Issues With Electric Tankless Water Heaters?
When troubleshooting electric tankless water heaters, I first check the power supply to verify it’s on and functioning. I then inspect the circuit breaker and reset it if needed. Next, I examine the inlet filter for debris and clean it if clogged. If the water isn’t hot enough, I verify the temperature settings. Finally, I look for error codes on the unit and consult the manual for specific guidance.
What Are the Safety Features Included in Modern Models?
Modern electric tankless water heaters come equipped with essential safety features like automatic shut-off if overheating occurs, built-in pressure relief valves, and thermal cut-offs to prevent electrical hazards. They also often include leak detection systems and circuit breakers to protect against electrical surges. These safety measures give me peace of mind, knowing that my system is designed to operate safely and efficiently while providing instant hot water.
Can Electric Tankless Water Heaters Be Installed Outdoors?
I’ve installed outdoor electric tankless water heaters, and they work great when weather conditions are right. Like a sturdy umbrella in a storm, proper installation and weatherproofing are key. Most modern models are designed for outdoor use, featuring corrosion-resistant components and sealed enclosures. Still, I recommend checking the manufacturer’s guidelines to ascertain your unit can handle outdoor elements and avoid issues like freezing or water damage.
How Do Energy Efficiency Ratings Impact Operating Costs?
Energy efficiency ratings directly impact my operating costs because higher ratings mean I use less electricity to produce the same amount of hot water. When I choose a unit with a top efficiency rating, I save money on my energy bills over time. It’s worth investing in models with better ratings, as they help me reduce ongoing expenses and minimize my environmental footprint.
Are There Specific Maintenance Routines Recommended for Longevity?
Did you know that regular maintenance can extend a water heater’s lifespan by up to 50%? I recommend flushing the unit annually to remove mineral buildup, checking the anode rod, and inspecting for leaks. Keeping the filters clean and ensuring proper venting also helps. These simple routines not only prolong the life of your heater but also ensure it runs efficiently, saving you money and avoiding unexpected breakdowns.
Conclusion
Choosing the right electric tankless water heater is like selecting the perfect tool for a craft—precision and reliability matter. Whether you picture a small, efficient unit or a powerful system ready for a busy household, each option offers unique benefits. Remember, the best heater meets your needs without overwhelming your space or budget. So, weigh your options carefully, and you’ll enjoy instant hot water just like a well-oiled machine—smooth, seamless, and dependable.
