Finding the best 8 GPM electric tankless water heater means looking for a unit powerful enough to supply multiple fixtures simultaneously while maintaining consistent hot water. Electric tankless heaters with 8 GPM (gallons per minute) flow rates are typically higher-powered and ideal for large households or light commercial use. Here are the top-rated options that offer great performance, efficiency, and reliability:
1. Stiebel Eltron Tempra 36 Plus – Best Overall
The Stiebel Eltron Tempra 36 Plus is a high-performance electric tankless water heater capable of delivering up to 8 GPM, making it one of the best options for large households or commercial spaces. It features Advanced Flow Control, which adjusts water flow to ensure consistent temperature even when multiple fixtures are running simultaneously. This makes it perfect for homes with 2-3 showers in use at the same time or for businesses with high hot water demands.
Key Features:
- Flow Rate: Up to 8 GPM (depending on inlet water temperature)
- Power: 36 kW at 240V
- Best For: Large homes, restaurants, small commercial spaces
- Efficiency: 99% energy efficiency
- Advanced Flow Control: Automatically adjusts flow to maintain temperature
- Digital Temperature Control: Precise control between 68°F and 140°F
- Compact Design: Saves space and is easy to install
Pros:
- High flow rate, capable of handling multiple showers or sinks simultaneously
- Consistent water temperature thanks to Advanced Flow Control
- High energy efficiency, reducing utility costs
- Quiet operation and compact design
- Long warranty and excellent customer support
Cons:
- Requires a significant electrical setup with three 40-amp breakers
- Higher upfront cost compared to smaller units
2. EcoSmart ECO 36 – Best for Energy Efficiency
The EcoSmart ECO 36 is another great option for those who need an 8 GPM flow rate. It’s known for its self-modulating technology, which optimizes energy usage based on demand. This results in energy savings and lower utility bills. The compact design makes it easy to install in small spaces, and it’s ideal for large homes where multiple showers, dishwashers, and sinks might be used simultaneously.
Key Features:
- Flow Rate: Up to 8 GPM (at ideal inlet temperature)
- Power: 36 kW at 240V
- Best For: Large households, small businesses
- Efficiency: 99.8% energy efficiency with self-modulating technology
- Temperature Control: Adjustable up to 140°F
- Compact Size: Saves space and offers flexible installation options
Pros:
- Self-modulating technology for maximum energy savings
- Supports simultaneous use of multiple fixtures
- Compact, space-saving design
- Lifetime warranty on parts (for residential use)
- Affordable compared to other models with similar capacity
Cons:
- May struggle in colder climates where inlet water temperatures are lower
- Requires high amperage, needing electrical upgrades in some homes
3. Rheem RTEX-36 – Best for High-Demand Applications
The Rheem RTEX-36 is designed to handle large-scale hot water needs, making it one of the best choices for households or commercial settings requiring 8 GPM flow rates. It features external digital thermostatic control with an LED display, which allows precise temperature adjustments. It’s perfect for homes or small businesses with multiple showers, washing machines, and dishwashers running at the same time.
Key Features:
- Flow Rate: Up to 8.8 GPM (depending on inlet water temperature)
- Power: 36 kW at 240V
- Best For: Large homes, gyms, small commercial spaces
- Efficiency: 99.8% energy efficiency
- Digital Thermostatic Control: Accurate temperature adjustment from 80°F to 140°F
- Durability: Commercial-grade construction for heavy use
Pros:
- High flow rate for large homes and commercial use
- Digital temperature control for precise settings
- Can handle multiple fixtures running simultaneously
- Compact design, easy to install in tight spaces
- Energy-efficient operation
Cons:
- May require significant electrical upgrades
- Slightly more expensive than some other 36 kW models
4. Bradford White Infiniti K Series Electric Tankless – Best for Recirculation Systems
The Bradford White Infiniti K Series is a high-efficiency electric tankless water heater that offers recirculation technology, meaning it delivers hot water almost instantly while reducing water waste. This unit is capable of delivering 8 GPM of hot water and is ideal for homes that require hot water across multiple fixtures simultaneously. It’s built with high-end materials like a stainless steel heat exchanger, ensuring durability and longevity.
Key Features:
- Flow Rate: Up to 8 GPM
- Power: 36 kW at 240V
- Best For: Large homes with recirculation systems, commercial use
- Efficiency: High energy efficiency with low standby heat loss
- Recirculation Technology: Ensures instant hot water
- Durable Design: Stainless steel heat exchanger for long life
Pros:
- Ideal for homes with recirculation systems, providing instant hot water
- High flow rate, suitable for large families or commercial settings
- Durable and long-lasting construction
- Reduces water waste, improving overall efficiency
- Handles multiple fixtures without temperature fluctuations
Cons:
- More expensive due to advanced technology and materials
- Requires professional installation and significant electrical infrastructure
5. Eemax EEM24036 – Best Budget-Friendly High Flow
The Eemax EEM24036 is a budget-friendly option for households or small businesses that require a high flow rate. It delivers up to 8 GPM of hot water, making it suitable for homes with multiple showers, sinks, or appliances running simultaneously. It also includes self-modulating technology, allowing it to adjust energy usage based on demand, making it efficient for its price.
Key Features:
- Flow Rate: Up to 8 GPM
- Power: 36 kW at 240V
- Best For: Large homes, small commercial spaces
- Efficiency: 99% energy efficiency with self-modulating technology
- Temperature Control: Digital control for precise temperature settings
- Compact and Affordable: Great balance of performance and price
Pros:
- High flow rate at a more affordable price
- Self-modulating technology reduces energy consumption
- Compact size makes installation easy in tight spaces
- Handles multiple fixtures without issues
Cons:
- May not be as durable as more premium models
- Requires professional installation due to electrical demands
Comparison Table: Best 8 GPM Electric Tankless Water Heaters
| Model | Best For | Flow Rate (GPM) | Power (kW) | Efficiency | Key Features | Price Range |
|---|---|---|---|---|---|---|
| Stiebel Eltron Tempra 36 Plus | Best Overall, large homes | 8 GPM | 36 kW | 99% | Advanced Flow Control, digital control | $$$$ |
| EcoSmart ECO 36 | Energy efficiency, large homes | 8 GPM | 36 kW | 99.8% | Self-modulating tech, compact design | $$$ |
| Rheem RTEX-36 | High-demand homes, commercial use | 8.8 GPM | 36 kW | 99.8% | Digital thermostatic control, high flow rate | $$$$ |
| Bradford White Infiniti K | Homes with recirculation systems | 8 GPM | 36 kW | High Efficiency | Recirculation system, stainless steel heat exchanger | $$$$$ |
| Eemax EEM24036 | Budget-friendly, high flow | 8 GPM | 36 kW | 99% | Self-modulating, digital control | $$ |
Factors to Consider When Choosing an 8 GPM Electric Tankless Water Heater
- Flow Rate (GPM):
- An 8 GPM flow rate ensures you can use multiple showers, sinks, and appliances simultaneously without running out of hot water. Consider whether this capacity will meet your home’s peak hot water demand.
- Power (kW):
- Higher-powered units, such as 36 kW, can handle large homes or commercial applications. Keep in mind that you may need to upgrade your home’s electrical system to accommodate the higher amperage these units require.
- Efficiency:
- Look for units with 99% or higher energy efficiency to minimize electricity costs. Models with self-modulating technology like the EcoSmart ECO 36 and Eemax EEM24036 adjust energy usage based on demand, making them more efficient.
- Temperature Control:
- Digital thermostatic control allows you to set the exact temperature you need, which is useful when running multiple fixtures that require precise water temperatures.
- Installation Requirements:
- Larger electric tankless water heaters often require dedicated circuits and upgraded electrical panels. Make sure your home or business can support the required power and installation.
Final Recommendation
- For best overall performance, the Stiebel Eltron Tempra 36 Plus is unmatched in delivering consistent hot water with its advanced flow control and energy-efficient design.
- If you’re looking for energy efficiency and cost savings, the EcoSmart ECO 36 is a top choice thanks to its self-modulating technology and compact design.
- For high-demand commercial or residential use, the Rheem RTEX-36 provides robust performance with precise temperature control and a high flow rate.
- If you need instant hot water with a recirculation system, the Bradford White Infiniti K Series is the best option for long-term durability and performance.
- For those on a budget, the Eemax EEM24036 delivers high flow rates and efficient water heating at a lower price point.
By choosing the right 8 GPM electric tankless water heater, you can ensure that your home or business will have reliable, on-demand hot water while maximizing energy efficiency.