Electric Tankless Hot Water Heaters: What to Know Before You Buy or Install

Introduction: Why Electric Tankless Hot Water Heaters Are In Demand

Tired of running out of hot water—or paying high utility bills? You’re not alone. More and more homeowners are turning to the electric tankless hot water heater as a smarter, more efficient way to get hot water on demand.

Unlike traditional water heaters that store and continuously heat a large tank of water, tankless electric hot water heaters activate only when you turn on the tap. This means you’re not paying to heat water you’re not using—translating to energy savings, lower utility costs, and a longer-lasting system.

Electric models, in particular, are rising in popularity thanks to their:

• Compact, space-saving design
• Easy installation (especially in all-electric homes)
• Lower upfront costs compared to gas tankless systems
• High efficiency and minimal maintenance needs

Whether you’re upgrading your current water heater or exploring options for a new home, a tankless hot water heater electric system offers real advantages in performance, efficiency, and convenience.

But with so many models, sizes, and features to choose from—not to mention questions about installation, cost, and whether to go gas or electric—it can be overwhelming to know where to start.

That’s why we created this complete guide. In the sections ahead, we’ll explore:

• How electric tankless water heaters work
• How they compare to gas models
• The best electric tankless hot water heater options for your home or business
• What they cost
• What real reviews say—and whether they’re the right fit for your lifestyle

Table of Contents

• What Is an Electric Tankless Hot Water Heater?
• How Electric Tankless Water Heaters Work
• Benefits of Tankless Hot Water Heater (Electric Models)
• Tankless Hot Water Heater: Electric vs. Gas
• Best Electric Tankless Hot Water Heaters in 2025
• Choosing a Whole House Electric Tankless Hot Water Heater
• Small Electric Tankless Hot Water Heaters for Compact Spaces
• Commercial Electric Tankless Hot Water Heater Options
• Cost of Electric Tankless Hot Water Heaters: What to Expect
• Is an Electric Tankless Hot Water Heater Right for You?
• Why Hire Newwrx Plumbing for Installation
• Final Thoughts

What Is an Electric Tankless Hot Water Heater?

An electric tankless hot water heater—also known as an on-demand water heater—is a modern alternative to traditional storage tank water heaters. As the name suggests, it heats water only when you need it, without storing a supply of hot water in a tank.

Unlike conventional units that keep water hot 24/7 (and waste energy doing so), a hot water heater electric tankless system activates the moment you turn on a tap. Water flows through high-powered electric heating elements, warming up instantly as it passes through the unit—delivering a continuous supply of hot water for showers, sinks, appliances, or even your whole home.

How It Differs from Traditional Water Heaters

Traditional electric water heaters use a large tank (typically 30–80 gallons) to store heated water. This creates “standby energy loss”—where energy is used to maintain the tank’s temperature even when you’re not using hot water.

In contrast, an electric hot water heater tankless model heats water on demand, offering several key differences:

Why More Homeowners Are Making the Switch

As energy efficiency, sustainability, and cost savings become top priorities for homeowners, the electric tankless hot water heater is quickly gaining ground as the go-to solution. Not only does it reduce energy waste, but it also frees up valuable floor space and eliminates the common frustration of running out of hot water mid-shower.

Whether you’re building a new home, upgrading your water system, or simply tired of your outdated tank setup, a tankless system is worth considering—especially in smaller homes, energy-conscious households, or all-electric properties.

How Electric Tankless Water Heaters Work

Understanding how an electric tankless hot water heater works can help you decide if it’s the right fit for your home or business. These systems are efficient, compact, and built for performance—but their technology operates quite differently from traditional storage tank heaters.

Here’s a simple breakdown of how a the system works:

1. Water Flow Triggers the System

When you turn on a hot water tap, cold water begins flowing through the unit. Inside the tankless electric hot water heater, a flow sensor detects this movement and activates the internal electric heating elements.

2. Instant Heating Begins

Rather than heating a full tank in advance, electric tankless systems rapidly heat water as it flows through coiled or flat electric elements—raising the water to your desired temperature in real time.

Because there’s no storage involved, you get an uninterrupted flow of hot water for as long as you need it (within the system’s flow rate capacity)

3. Precision Temperature Control

Most modern electric tankless systems include digital thermostats that let you set and maintain an exact water temperature. These controls help prevent overheating and ensure comfort, especially when multiple water outlets are in use.

4. Automatic Shutoff When Water Stops Flowing

Once you turn off the tap or the appliance finishes its cycle, the water stops flowing—and so does the unit. This on-demand functionality is one of the key reasons why electric tankless hot water heaters are considered energy-smart and highly efficient.

Benefits of Tankless Hot Water Heater (Electric Models)

Electric tankless systems offer a wide range of advantages that appeal to homeowners, property managers, and business owners alike. Whether your goal is to reduce energy bills, save space, or ensure a steady supply of hot water, an electric tankless hot water heater can deliver big results.

Endless Hot Water on Demand

One of the biggest advantages of a tankless hot water heater electric model is its ability to deliver hot water whenever you need it—without running out. Traditional tank systems are limited by their storage capacity. Once the tank is empty, you’re left waiting for it to refill and reheat. Tankless systems heat water on demand, so there’s virtually no limit as long as the unit’s flow rate matches your usage.

Greater Energy Efficiency

Because they only activate when water is being used, electric tankless water heaters don’t waste energy maintaining a hot water reserve like traditional tanks do. This on-demand approach can lead to significant energy savings over time—especially in smaller households or properties with lower hot water usage.

Compact, Space-Saving Design

An electric hot water heater tankless model is typically wall-mounted and much smaller than a bulky storage tank. This makes it ideal for homes with limited space, apartments, condos, or even under-sink installations. You’ll free up utility closet or garage space and enjoy a cleaner, more modern setup.

Longer Lifespan and Lower Maintenance

Electric tankless water heaters tend to last longer than traditional tank models—often 15 to 20 years with proper care. They also have fewer moving parts and are less susceptible to corrosion since they don’t store water. With less risk of sediment buildup and no tank to rupture, maintenance is simpler and costs are lower over the long term.

Eco-Friendly Performance

Because they waste less energy and water, tankless electric hot water heaters are more environmentally friendly than older heating systems. They also reduce greenhouse gas emissions when compared to gas models, making them a good option for eco-conscious homeowners.

Consistent Water Temperature

Modern tankless systems use advanced sensors and digital controls to maintain a steady water temperature. This means no more unpleasant fluctuations during showers or when multiple taps are in use.

Easy Integration in Electric Homes

If your home doesn’t have a gas line—or you’re committed to staying all-electric—then a tankless electric hot water heater is a practical, cost-effective solution. You won’t need to install gas hookups or worry about venting, which can simplify installation and reduce costs.

Tankless Hot Water Heater: Electric vs. Gas

One of the most common questions homeowners ask when considering a tankless upgrade is: Should I choose electric or gas? Both types of tankless water heaters offer energy efficiency, space savings, and endless hot water. But when it comes to performance, cost, and convenience, the right choice often depends on your household needs, home infrastructure, and energy preferences.

If you’re comparing a tankless hot water heater, electric vs gas, here’s what you need to know:

Energy Source and Availability

Electric tankless water heaters are ideal for homes that are already powered entirely by electricity or where installing a gas line would be costly or unnecessary. Gas models, on the other hand, require access to natural gas or propane and proper venting, which can add to installation costs—especially if those systems don’t already exist in your home.

For many homeowners in urban areas or newer homes, electric is the more accessible and streamlined choice.

Installation and Maintenance

Electric tankless models are typically easier and more affordable to install than gas units. They don’t require gas hookups, combustion venting, or carbon monoxide monitoring. That makes electric models especially appealing for retrofits, small homes, apartments, and tight mechanical spaces.

Gas tankless units have more complex installation requirements, and their burners and vents require ongoing maintenance. In contrast, electric units have fewer moving parts, which means less can go wrong over time.

Energy Efficiency

Both electric and gas tankless systems are more energy-efficient than traditional tank models, but electric tankless hot water heaters often achieve higher energy factor (EF) ratings. They convert nearly all of the electricity they use into heat with minimal loss, whereas gas units may waste some energy in the form of exhaust heat.

If efficiency and reducing energy waste are top priorities, electric typically comes out ahead.

Operating Costs

Gas is generally cheaper per BTU than electricity, which means tankless gas water heaters can be more cost-effective for homes with high hot water demand. However, this advantage may be offset by the higher maintenance and installation costs associated with gas systems.

Electric models may cost slightly more to operate depending on local utility rates, but they also tend to be more efficient—especially in moderate-use households—so your overall monthly costs may be comparable or even lower in the long run.

Flow Rate and Heating Power

Gas tankless water heaters usually offer higher flow rates and can handle multiple simultaneous uses better than small electric units. That’s why they’re often recommended for large families or homes with multiple bathrooms.

However, modern whole house electric tankless hot water heaters have come a long way and can easily support two to three fixtures at once with the right unit.

Environmental Considerations

Electric tankless systems are the more environmentally friendly option in many cases—especially when powered by renewable electricity. They produce zero on-site emissions, whereas gas systems contribute to greenhouse gas emissions.

For homeowners seeking a cleaner, greener solution, electric tankless wins in terms of carbon footprint and sustainability.

Which One Is Right for You?

Choose a tankless electric hot water heater if:

• Your home is all-electric or lacks a gas line
• You want lower installation costs and simpler maintenance
• You’re prioritizing efficiency and sustainability
• You live in a smaller home, condo, or apartment
• You want a space-saving solution for retrofitting older homes

Choose gas if:

• You have a high household demand for simultaneous hot water use
• Your home is already plumbed for natural gas
• You prefer lower operating costs in areas with expensive electricity

Best Electric Tankless Hot Water Heaters in 2025

With so many models available, finding the right unit can feel overwhelming. The truth is, the best model depends on your unique needs—how much hot water you use, the size of your home, and whether you’re looking for a whole-house system or a point-of-use solution.

To make your decision easier, here are some of the top-performing electric tankless hot water heaters in 2025, based on efficiency, performance, reliability, and customer reviews.

Stiebel Eltron Tempra Plus Series

Known for its German engineering and ultra-reliable performance, the Stiebel Eltron Tempra Plus is a favorite for whole-house use. It features advanced flow control technology to maintain consistent water temperature, even when multiple outlets are running.

Best for: Large households, energy efficiency, long-term value GPM Range: 4.0–7.5 Notable Features: Digital temperature control, compact design, quiet operation

EcoSmart ECO 27

One of the most popular models in the U.S., the EcoSmart ECO 27 is ideal for mid-size homes in moderate climates. It’s known for excellent energy efficiency and affordability.

Best for: Homes with up to 3 bathrooms, budget-conscious buyers GPM Range: 2.7–6.5 Notable Features: Self-modulating technology, easy installation, lifetime warranty (limited)

Rheem RTEX-18

A reliable name in water heating, Rheem’s RTEX line offers solid performance and good flow rates. The RTEX-18 is a compact, powerful option that’s great for smaller homes or apartments.

Best for: Small-to-medium homes, energy-conscious homeowners GPM Range: 2.5–4.4 Notable Features: LED display, external digital thermostat, durable copper immersion elements

Bosch Tronic 6000C WH27

Bosch’s Tronic 6000C delivers consistent performance with a durable design and high-quality materials. It’s ideal for homeowners who want solid brand backing and a reliable system for long-term use.

Best for: Mid-size homes, brand-conscious buyers GPM Range: 2.8–5.4 Notable Features: Sleek design, silent operation, backed by a strong warranty

Eemax EEM24036

If you need power and performance, the Eemax EEM24036 is a heavy-duty electric tankless unit built to handle larger homes or higher water demands.

Best for: Whole-house use in colder climates, high-flow fixtures GPM Range: 3.0–6.0 Notable Features: Compact housing, energy-efficient design, robust heating capacity

Each of these models has its own strengths, and the best choice comes down to your hot water usage and local energy considerations.

Choosing a Whole House Electric Tankless Hot Water Heater

If you’re looking for a single solution to supply endless hot water throughout your entire home, a whole house electric tankless hot water heater may be exactly what you need. These systems are powerful enough to deliver hot water to multiple fixtures simultaneously—think showers, sinks, dishwashers, and laundry machines—all without running out.

But choosing the right whole-house system isn’t as simple as picking the most expensive model. It requires understanding your household’s hot water demands, sizing the unit properly, and ensuring your home’s electrical system can support it. Here’s what to consider.

Start by calculating your home’s peak hot water usage. This is typically measured in gallons per minute (GPM). For example:

• A standard shower uses 1.5 to 2.5 GPM
• A kitchen faucet may use 1.0 to 1.5 GPM
• A washing machine might use 2.0 GPM

If you expect to run two showers and a washing machine at the same time, your total demand could be 6.5 to 7.5 GPM. In this case, you’d want an electric tankless model that can handle at least that flow rate without sacrificing water temperature.

Next, consider your climate. In colder regions, incoming water is colder and takes more energy to heat, which means you’ll need a higher-capacity unit to reach desired temperatures. Homes in warmer climates can often use lower-capacity systems to achieve the same result.

Your home’s electrical panel also plays a major role. Whole-house electric tankless units require significant amperage—sometimes up to 150 amps or more. Before purchasing a system, you’ll need to make sure your electrical infrastructure can support it. If not, upgrades may be necessary.

Small Electric Tankless Hot Water Heaters for Compact Spaces

Not every home or property needs a whole-house solution. In fact, if you’re remodeling a small bathroom, upgrading an RV, outfitting a tiny home, or just want to improve hot water access in a remote part of the house, a small electric tankless hot water heater may be the perfect fit.

These compact units are designed for point-of-use applications, meaning they’re installed close to where hot water is needed—such as under a sink or near a single shower. They heat water instantly at the source, eliminating the delay and energy waste of sending water from a distant central tank.

Small tankless units are especially useful in:

• Studio apartments
• Guest bathrooms
• Garage or outdoor sinks
• Kitchenettes and wet bars
• Office break rooms
• RVs and camper vans

Because of their smaller heating capacity, these systems aren’t built to run multiple fixtures at once. However, they excel at delivering hot water quickly and efficiently to one or two fixtures, without taking up valuable space.

Benefits of small electric tankless hot water heaters include:

• Ultra-compact design that fits in tight spaces
• Lower energy consumption and operating costs
• No standby heat loss compared to tank-style units
• Easy and fast installation
• Minimal maintenance

Models like the EcoSmart POU 3.5, Stiebel Eltron Mini series, and Bosch Tronic 3000 are popular choices for single-sink applications or compact homes. Some plug directly into standard 120V outlets, while others require a dedicated 240V line for faster heating and higher flow rates.

As with whole-house units, sizing is still important. Even for small tankless systems, matching the GPM output to your fixture’s flow rate and expected usage ensures consistent temperature and performance.

Commercial Electric Tankless Hot Water Heater Options

For businesses that rely on consistent hot water to operate smoothly, a commercial electric tankless hot water heater offers an efficient, reliable, and space-saving alternative to bulky tank systems. Whether you’re running a restaurant, salon, medical facility, retail shop, or office building, having hot water on demand is not just a luxury—it’s a necessity.

Unlike residential units, commercial-grade electric tankless systems are engineered for higher flow rates, greater durability, and continuous operation under heavier loads. They’re designed to handle multiple fixtures at once without sacrificing water temperature or pressure, even during peak usage.

Some of the most common applications for commercial electric tankless heaters include:

• Restaurants and cafes (dishwashing, restrooms, prep sinks)
• Hair and nail salons (shampoo stations, handwashing)
• Gyms and locker rooms (multiple showers in use simultaneously)
• Hotels and motels (guest room showers and bathrooms)
• Medical clinics and dental offices (sterilization, hand hygiene)
• Multi-family buildings and apartment complexes

These systems offer several advantages in commercial environments:

• Unlimited hot water when properly sized
• Compact installation with wall-mounted units
• Lower long-term operating costs compared to tank systems
• Reduced maintenance and no risk of tank failure
• Flexible installation in tight or unconventional spaces

Because commercial setups often have greater hot water demands, proper sizing and configuration are essential. Additionally, commercial electric tankless water heaters typically need robust electrical infrastructure to support high amperage requirements.

Cost of Electric Tankless Hot Water Heaters: What to Expect

Understanding the electric tankless hot water heater cost is a key part of deciding whether this upgrade is right for your home or business. While tankless systems often have a higher upfront price than traditional tank models, their long-term energy savings, lower maintenance requirements, and extended lifespan make them a smart investment for many property owners.

Let’s break down the costs involved so you know what to expect.

The cost of the unit itself varies based on size, brand, and performance:

• Small, point-of-use models: $150 – $400
• Mid-range residential models: $500 – $900
• Whole-house units: $900 – $1,800+
• Commercial-grade models: $1,500 – $3,500+

Installation costs also vary depending on several factors:

• Labor and setup: $500 – $1,500
• Electrical upgrades (if required): $500 – $2,000+
• Permitting and inspections: $100 – $300

For a full system installation, including labor and potential panel upgrades, the total project cost for a whole house electric tankless hot water heater may range between $1,800 and $4,500 on average. For larger commercial projects, total system costs may exceed $5,000 depending on complexity and scale.

While this may seem like a significant investment, it’s important to consider long-term savings. Electric tankless systems typically reduce energy bills up to 34% compared to traditional electric tank systems. And with a lifespan of up to 20 years—nearly double that of many tank models—the cost of ownership over time is often lower.

Other savings to keep in mind:

• No need for regular tank flushing or sediment maintenance
• Reduced risk of costly leaks or ruptures
• Space savings that can free up square footage in tight mechanical rooms

Additionally, some homeowners may qualify for energy-efficiency rebates or local incentives, especially when replacing outdated water heaters with ENERGY STAR–rated models.

Is an Electric Tankless Hot Water Heater Right for You?

By now, you’ve learned how an electric tankless hot water heater works, its benefits, and how it compares to gas-powered systems. But the real question is—is it the right solution for your home or business?

The answer depends on a few key factors, including your household’s hot water usage, your existing electrical system, your goals for energy efficiency, and the physical space available for installation.

Here’s how to tell if an electric tankless system is the right fit for you:

You’re in an All-Electric Home

If your home doesn’t have a gas line—or if you’re trying to move away from fossil fuels—an electric tankless system is a natural choice. It installs cleanly without the need for gas ventilation and integrates seamlessly into electric-only infrastructures.

You Want Energy Savings Without Sacrificing Comfort

If reducing your energy bill is a top priority, electric tankless systems are highly efficient—heating water only when you need it.

You Don’t Have a Lot of Space

Electric tankless water heaters are compact and wall-mounted, freeing up floor space in closets, garages, and utility rooms. They’re perfect for smaller homes, condos, and ADUs where every square foot matters.

You Have Light to Moderate Hot Water Demand

If your household typically runs one to two fixtures at a time—like a shower and a sink—electric tankless units can easily keep up with demand. For larger homes, multiple units or higher-capacity models can also be installed to meet whole-house needs.

You’re Replacing an Old or Inefficient Water Heater

If your current water heater is 10+ years old, inefficient, or constantly running out of hot water, now is the perfect time to upgrade. An electric tankless system can improve your comfort while reducing maintenance headaches.

Still not sure? Here’s a quick checklist:

• Does your home already have the electrical capacity for a tankless system?
• Do you want to eliminate standby energy loss?
• Are you interested in a more eco-friendly water heating solution?
• Would you prefer to never run out of hot water again?

If you answered “yes” to most of the above, then an electric tankless hot water heater could be the ideal solution for your home or business.

Why Hire Newwrx Plumbing for Installation

Choosing the right electric tankless hot water heater is just the first step—having it installed correctly is just as important. These systems require precise electrical work, correct sizing, and expert configuration to function efficiently and safely. That’s where Newwrx Plumbing comes in.

As a trusted local plumbing company serving Sacramento, South Lake Tahoe, and surrounding areas, Newwrx Plumbing offers professional electric tankless water heater installation backed by years of hands-on experience. We don’t just sell or install units—we tailor each system to your home’s unique needs.

Here’s why homeowners and businesses trust us:

Expert Sizing and Custom Recommendations

Every home is different, and there’s no one-size-fits-all solution. Our team will calculate your household’s peak water demand, consider your climate, and assess your electrical panel to recommend the perfect unit—whether it’s a small point-of-use heater or a whole house electric tankless hot water heater.

Licensed, Code-Compliant Installation

Improper installation can lead to performance issues, code violations, or even safety risks. Our licensed plumbers and electricians ensure your system is installed to the latest safety standards and local building codes. We handle permits, inspections, and every detail so you don’t have to.

Electrical System Compatibility Checks

Tankless electric systems often require significant amperage. We’ll evaluate your electrical panel and, if needed, coordinate upgrades to ensure your new system runs safely and efficiently—without tripping breakers or overloading circuits.

Long-Term Support and Service

When you work with Newwrx Plumbing, you’re not just getting a product—you’re gaining a reliable service partner. We provide maintenance, troubleshooting, and repairs for all major brands of electric tankless water heaters, so you always have support if something goes wrong.

Local Knowledge, Fast Service

We understand the local building codes, utility requirements, and climate-related needs specific to homes and businesses in Sacramento, South Lake Tahoe, and nearby areas. That local insight allows us to deliver fast, dependable, and personalized service every time.

Whether you’re upgrading your existing system, building new, or switching from gas to electric, Newwrx Plumbing is your go-to expert for efficient, hassle-free installation. We make the process simple—so you can enjoy the comfort, savings, and reliability of your new electric tankless hot water heater without stress.

Final Thoughts

Upgrading to an electric tankless hot water heater is one of the smartest moves you can make for energy efficiency, convenience, and long-term cost savings. Whether you’re a homeowner tired of running out of hot water, a business owner needing consistent performance, or simply looking to modernize your property’s plumbing, tankless technology offers a future-ready solution that fits.

Contact Newwrx Plumbing today to schedule your consultation and get a custom quote for your new electric tankless hot water heater. Let’s upgrade your comfort, lower your energy bills, and ensure you never run out of hot water again.