Electric tankless water heaters typically max out at a flow rate of 7-8 GPM. Reaching 10 GPM with an electric unit is extremely challenging due to the power limitations of most residential electrical systems. However, natural gas and propane tankless water heaters often achieve this kind of flow rate. For those specifically looking for high-flow electric models, here are the best available options in the 7-8 GPM range, which come closest to your needs.
1. Stiebel Eltron Tempra 36 Plus
- Flow Rate: 7.5 GPM
- Power: 36 kW
- Why It’s Great: This is one of the most powerful electric tankless heaters on the market, ideal for larger homes needing significant hot water. Its advanced flow control ensures hot water remains consistent even when multiple fixtures are in use.
- Key Features:
- Self-modulating technology for energy savings.
- Digital temperature control with precise settings.
- Extremely reliable for larger households.
- Best For: Homes needing high flow rates in warmer climates (as performance diminishes slightly in colder climates).
2. EcoSmart ECO 36
- Flow Rate: 6.5-7.0 GPM (depending on incoming water temperature)
- Power: 36 kW
- Why It’s Great: Known for its energy efficiency and self-modulating technology, the EcoSmart ECO 36 is capable of heating water for up to three showers and two sinks simultaneously in warmer climates.
- Key Features:
- Digital control for setting temperature precisely.
- Compact and easy to install.
- Great energy savings due to its self-modulation feature.
- Best For: Medium to large homes where multiple points of use (showers, faucets) need to run simultaneously.
3. Rheem RTEX-36
- Flow Rate: 6.5-7.0 GPM
- Power: 36 kW
- Why It’s Great: Rheem’s RTEX-36 offers external digital thermostats with LED displays for easy temperature adjustments. The unit is compact and can fit in smaller spaces, but powerful enough to handle a high-demand household.
- Key Features:
- Self-modulating technology for maximum energy savings.
- Dual copper immersion heating elements for fast heating.
- Easy installation and maintenance.
- Best For: Homes needing a robust solution for multiple users, especially where water demands peak in the mornings or evenings.
4. Bosch Tronic 6000 WH36
- Flow Rate: 5.5-6.5 GPM
- Power: 36 kW
- Why It’s Great: Bosch’s Tronic 6000 WH36 is highly efficient and well-suited for whole-home applications. It works best in warmer climates but can still supply sufficient hot water for two to three bathrooms in moderate conditions.
- Key Features:
- Excellent temperature control.
- Compact size and easy-to-install.
- Self-modulating power to ensure energy savings.
- Best For: Smaller to medium-sized homes in warmer climates.
Why Electric Units Struggle to Reach 10 GPM:
Electric units generally require a significant amount of power to achieve the flow rates that gas tankless heaters can provide. At flow rates of 10 GPM, the unit would need an enormous electrical draw, which exceeds what is practical for most residential setups. For larger homes requiring 10 GPM, natural gas or propane tankless water heaters like the Rinnai RUR199iN or Navien NPE-240A are recommended as they can handle these demands more easily.
Conclusion:
If you are set on electric and need the highest possible flow rate, models like the Stiebel Eltron Tempra 36 Plus or EcoSmart ECO 36 are your best options. However, if you’re willing to consider natural gas, you could find more suitable options that consistently deliver 10 GPM or more, like the Rinnai RUR199iN.