Best Electric Tankless Water Heaters for Immediate Hot Water and Efficiency
Electric tankless water heaters provide on-demand hot water with compact designs, energy efficiency, and flexible installation options for homes and apartments. This guide highlights five top picks and what to consider when choosing the right model for 2–3 fixtures. Review specifications, installation requirements, and performance details to balance cost, efficiency, and hot-water reliability.
Summary Table of Selected Products
| Product | Brand | Max GPM | Voltage | Key Feature |
|---|---|---|---|---|
| 18kW Tankless Water Heater Electric, ORBEK | Orbek | Up to 4.17 | 240V | Supports 2–3 fixtures with high efficiency |
| 14kW Tankless Water Heater Electric, ORBEK | Orbek | Up to 3.38 | 240V | LED display, efficient on-demand |
| Rheem 18kW 240V Tankless Electric Water Heater | Rheem | Up to 4.4 | 240V | Digital thermostatic control with LED |
| ECOTOUCH 14kW 240V Tankless | ECOTOUCH | Up to 3.38 | 240V | Self-modulating, ETL certified |
| ECOTINYMACH Tankless Water Heater Electric 110V | ECOTINYMACH | Regarding 0.3–0.5 GPM ranges | 110V | Remote control operation |
Orbek 18kW Electric Tankless Water Heater
The 18kW Orbek electric tankless water heater provides up to 4.17 GPM, suitable for 2–3 fixtures simultaneously. It requires 2 x 240V/40A two-pole breakers, two runs of 8 AWG wire, and 3/4″ NPT water connections. A 150-amp minimum service panel is recommended to ensure reliable operation, especially with other high-power appliances in use. The unit emphasizes hot water on demand with a rapid 3-second response and uses water-electricity separation to reduce scale and corrosion, potentially yielding energy savings over traditional tank systems.
Orbek 14kW Electric Tankless Water Heater
This 14kW Orbek model operates at 240V with a 60A two-pole breaker and needs a single set of 6 AWG wires and 1/2″ NPT connections. It supports up to 3.38 GPM for 2–3 points of use, delivering instant hot water with quick response. Like other Orbek units, it emphasizes energy efficiency through separation of water and electricity, which helps minimize scale and corrosion and can contribute to lower operating costs when replacing a conventional tank heater.
Rheem 18kW 240V Tankless Electric Water Heater
Rheem’s 18kW unit features external digital thermostatic control with LED display and self-modulation to adjust power based on demand, ensuring consistent hot water. Its durable copper immersion heating elements and a field-serviceable design support reliability and ease of maintenance. This model can deliver up to 4.4 GPM, making it a robust choice for households with higher hot-water needs or multiple fixtures running simultaneously at higher flow rates.
ECOTOUCH 14kW 240V Tankless Water Heater
ECOTOUCH’s 14kW model requires a 60A double-pole breaker and 6 AWG/2 wires with grounding. It provides up to 3.38 GPM for 2–3 fixtures and uses self-modulating technology to optimize energy use. The unit is ETL certificated and designed to limit scale and corrosion while delivering stable hot water in seconds. It emphasizes safety with built-in protections and a compact footprint suitable for wall installation or point-of-use setups.
ECOTINYMACH Tankless Water Heater Electric 110V
Designed for 110V operation, the ECOTINYMACH unit delivers on-demand hot water with a compact, space-saving form. The remote control feature adds convenience, allowing precise temperature adjustments. This model is suitable for installations such as under-sink setups, kitchens, or small bathrooms where space is at a premium, offering quick warmth without the need for bulky storage tanks.
Buying Guide: Key Purchase Considerations And Comparisons
- Flow rate requirements: Determine the maximum gallons per minute (GPM) you need to support simultaneous hot water use (e.g., two sinks plus a shower). Higher kW models generally deliver higher GPM, but check actual performance at your climate and inlet water temperature.
- Electrical capacity: Electric tankless heaters demand substantial electrical service. Confirm available amperage and panel capacity (for example, 150A or more may be recommended for some setups) and ensure you have dedicated breakers per unit as specified by the manufacturer.
- Voltage and breaker sizing: 110V units are typically for very light use and under-sink applications, while 240V models require appropriate double-pole breakers and thicker gauge wiring (6 AWG or 8 AWG depending on the model).
- Self-modulating technology: Many models use smart controls to adjust power delivery based on demand, improving energy efficiency and protecting against overheating. This feature is especially beneficial when hot-water demand fluctuates.
- Water temperature rise and inlet water temperature: Performance varies with inlet water temperature. In cooler climates, a given unit may deliver lower GPM than in warmer climates; verify performance curves provided by the manufacturer.
- Installation location and space: Tankless heaters are compact but require ventilation for exhaust-free operation on the electrical side and proper clearance around plumbing and electrical connections. Consider point-of-use versus whole-home placement.
- Safety features and certifications: Look for ETL or UL certifications, leakage protection, over-temp protection, and dry-burning protections. These features can impact safety and longevity of the unit.
- Maintenance and serviceability: Some models offer field-serviceable elements or easier access for annual checks. Consider units with copper immersion elements for durability and heat transfer efficiency.
- Remote control and display: A digital display or remote control can simplify temperature adjustments and monitoring, particularly for under-sink applications or multi-point use.
- Cost of operation: While prices vary, electric tankless heaters generally reduce standby energy waste. Consider long-term energy savings against upfront installation costs and electrical upgrades.
When selecting among these options, match your home’s current electrical capacity, climate, and hot-water needs with the unit’s GPM rating, voltage, and breaker requirements. For homes with limited electrical service, compatibility with existing panels and potential upgrades should be evaluated with a licensed electrician.