Need dependable hot water without the standby losses of a storage tank? The right commercial electric tankless water heater can deliver compact, on-demand performance for sinks, showers, and multi-point use.
Below, we focus on models that balance power, flow rate, control features, and installation practicality so you can match the unit to your business needs with confidence.
Best 10 Commercial Electric Tankless Water Heaters Picks for 2026
Whole-Home Power Pick
Rheem RTEX-24 24kW Electric Tankless Heater
- 24kW output with up to 5.9 GPM
- 1-degree digital temperature adjustment
- No venting and wall-mounted design
Best For: Whole-home installs with strong electrical service
High-Capacity Value Choice
EcoSmart ECO 27 27kW Tankless Heater
- 27kW output with nearly 3 GPM heating
- Built for incoming water as low as 37°F
- Self-modulating with 1-degree digital control
Best For: Cold-climate installs needing high output
Compact High-Output Option
Rheem RTEX-18 18kW Tankless Heater
- 18kW output with up to 4.4 GPM
- External LED thermostat with 1-degree accuracy
- Copper heating elements are field serviceable
Best For: Smaller whole-home or light commercial use
Premium Efficiency Pick
Stiebel Eltron Tempra 24 Trend 24kW Heater
- 24kW whole-house on-demand heating
- Auto-modulation and silent operation
- 7-year leakage and 3-year parts warranties
Best For: Quiet, efficient installs with strong warranty focus
High-Capacity Pick
Rheem RTEX-36 36kW Electric Tankless Water Heater
- 36kW heating power
- Up to 6 GPM flow rate
- External temperature control
Best For: Larger homes or light commercial spaces needing strong on-demand hot water
Heavy-Duty Whole-House Pick
NOVIEEX 27kW Tankless Water Heater
- Up to 7.4 GPM flow
- 1°F temperature control
- 8-layer safety protection
Best For: Larger installs needing high flow and precise temperature control
Best with Extra Features
36kW Electric Tankless Water Heater
- Up to 8.7 GPM for whole-house use
- WiFi control and self-modulating output
- Requires 300A service and 4 breakers
Best For: Large homes with enough electrical service for a high-output tankless system
Compact Sink-and-Shower Option
14kW Electric Tankless Water Heater
- Instant heating with up to 99.8% efficiency
- LED display with 1°F temperature control
- Best for under-sink or wall-mounted installs
Best For: Small spaces and lighter-demand sink or shower setups
Medium-Capacity Space Saver
18kW Electric Tankless Water Heater
- Up to 4.9 GPM for 2-3 points
- Ultra-thin wall-mount design
- 8-layer safety system with fault diagnosis
Best For: Apartments and medium homes needing compact multi-fixture hot water
Whole-Home Power Pick – Rheem RTEX-24 24kW Electric Tankless Heater
If you’re comparing commercial electric tankless water heaters for high-demand whole-home use, the Rheem RTEX-24 is built around output and straightforward control. Its 24kW, 240V design, adjustable digital temperature display, and up to 5.9 GPM flow rate make it a practical option when you need continuous hot water and have the electrical capacity to support it.
Best For: Whole-home installs where strong electrical service and simple temperature adjustment matter most.
Pros:
- 24kW output with up to 5.9 GPM flow rate for continuous hot water
- Adjustable digital temperature display with 1-degree increments from 80-140°F
- No venting required, which helps save space in the installation area
- Includes fittings and aerators, plus a limited lifetime warranty
Cons:
- Requires 3 x 40 amp double pole breakers and a recommended 200 amp household service
- Performance depends on incoming ground water temperature and location
- Only suitable where the breaker panel has enough room and power capacity
The RTEX-24 is a strong fit when you want a high-output electric tankless unit with simple controls and a compact wall-mounted footprint. Just make sure your electrical system can support the load before committing.
High-Capacity Value Choice – EcoSmart ECO 27 27kW Tankless Heater
The EcoSmart ECO 27 is a serious contender in commercial electric tankless water heaters when you need high output and precise control. It’s configured for colder climates, can handle incoming water as low as 37 degrees, and uses patented self-modulating technology to match heating to demand.
Best For: Cold-climate applications that need strong output and digital temperature control.
Pros:
- 27kW unit with capacity to heat nearly 3 GPM
- Works in climates with incoming water temperatures as low as 37°F
- Digital temperature control adjusts in 1-degree increments
- High-efficiency wall-mounted design with a limited lifetime warranty on key components
Cons:
- Requires 3 x 40 amp double pole breakers and 240V single-phase power
- Maximum temperature is listed at 120°F, lower than some competitors
- Warranty registration is required or coverage is void
If your priority is dependable hot water in colder incoming-water conditions, the ECO 27 offers a practical mix of output and smart modulation. It’s best suited to installations with the electrical infrastructure to support it.
Compact High-Output Option – Rheem RTEX-18 18kW Tankless Heater
For buyers comparing commercial electric tankless water heaters in a smaller footprint, the Rheem RTEX-18 offers a compact 18kW package with solid whole-home capability. It includes an external digital thermostatic control, self-modulation, and a flow rate up to 4.4 GPM, making it a practical choice when your demand is moderate but steady.
Best For: Smaller whole-home or light commercial setups that need a compact, field-serviceable unit.
Pros:
- 18kW heating with up to 4.4 GPM flow rate
- External LED digital thermostatic control with 1-degree accuracy
- Self-modulating operation helps match power to demand
- Durable copper immersion heating elements are field serviceable
Cons:
- Lower output than 24kW and 27kW alternatives
- Requires a suitable 240V electrical setup
- Best performance will depend on actual hot-water demand and incoming water temperature
The RTEX-18 is a sensible middle-ground option when space is tight and you still want digital control and reliable on-demand heating. It’s a good fit for buyers who don’t need the highest-capacity unit in the lineup.
Premium Efficiency Pick – Stiebel Eltron Tempra 24 Trend 24kW Heater
The Stiebel Eltron Tempra 24 Trend is a polished option for shoppers focused on efficiency, quiet operation, and a compact whole-house footprint. In the commercial electric tankless water heaters category, it stands out with auto-modulation, no venting required, and a clean digital temperature display for straightforward use.
Best For: Buyers who want an efficient, quiet wall-mounted heater with strong warranty coverage.
Pros:
- 24kW, 240V design with whole-house on-demand hot water
- Auto-modulation helps reduce wasted energy when demand changes
- Silent operation and no venting required
- Includes 7-year leakage and 3-year parts warranties
Cons:
- Requires a minimum recommended electric service of 150A
- Needs hard wiring and proper electrical planning
- Flow rate is not stated in the supplied details
If you value a quiet, space-saving unit with strong warranty support, the Tempra 24 Trend is easy to justify. It’s a refined choice, but like any high-powered electric tankless heater, it depends on having the right electrical service in place.
High-Capacity Pick – Rheem RTEX-36 36kW Electric Tankless Water Heater
Rheem RTEX-36 36kW Electric Tankless Water Heater 240V Ext Adj Temp Ctrl Bot 3/4 in. Npt Con
Check Price On AmazonFor buyers comparing commercial electric tankless water heaters, the Rheem RTEX-36 stands out as a high-output 240V unit built for demanding hot-water needs. Its 36kW heating power, 6 GPM flow rate, and external adjustable temperature control make it a practical choice when you need consistent on-demand hot water in a compact wall-mounted format.
Best For: Larger homes or light commercial spaces that need strong electric tankless performance with simple external temperature adjustment.
Pros:
- 36kW output supports high-demand hot water use.
- Up to 6 GPM flow rate for multiple fixtures.
- External adjustable temperature control adds convenience.
- Compact wall mount with bottom 3/4 in. NPT connections.
Cons:
- Requires 240V electric service.
- Flow capacity is lower than the highest-output models in this roundup.
Overall, the RTEX-36 is a straightforward pick if you want a proven electric tankless heater with a strong balance of output, adjustability, and compact installation. It is especially appealing when space is limited but hot-water demand is still substantial.
Heavy-Duty Whole-House Pick – NOVIEEX 27kW Tankless Water Heater
Among commercial electric tankless water heaters, the NOVIEEX 27kW model is positioned as a heavy-duty whole-house option with a strong 7.4 GPM maximum flow rate. It is designed for indoor wall installation and is built to handle 3 to 4 water applications at once, making it a compelling choice when you need higher output in a compact footprint.
Best For: Larger households or commercial-style installs that need high flow, multi-point use, and advanced safety features.
Pros:
- Up to 7.4 GPM supports 3 to 4 points of use.
- 1°F temperature adjustment with LED display.
- Compact wall-mount design saves space.
- 8-layer safety protection and smart fault self-diagnosis.
Cons:
- Requires professional installation and power verification.
- High electrical demand with 112.5A max current draw.
- Needs multiple double-pole breakers and heavy-gauge wiring.
If your priority is high-capacity electric hot water in a space-saving format, this NOVIEEX unit brings a lot to the table. Its high flow, precise temperature control, and safety package make it a strong fit for demanding use cases where installation requirements are not a concern.
Point-of-Use Pick – Rheem 11kW 240V Tankless Electric Water Heater
For buyers evaluating commercial electric tankless water heaters for smaller applications, the Rheem 11kW model is a compact point-of-use option with self-modulating power control and an adjustable digital temperature display. With up to 2.68 GPM flow and side 1/2 in. NPT connections, it fits well where you need reliable on-demand hot water without a large footprint.
Best For: Smaller installations, point-of-use setups, or low-flow applications that need a compact electric heater.
Pros:
- Compact wall-mounted design for tight spaces.
- Self-modulating power control helps maintain consistent output.
- Adjustable digital temperature display.
- 99.8% efficiency and limited lifetime warranty.
Cons:
- 11kW output is much lower than larger whole-house units.
- Maximum flow rate of 2.68 GPM limits multi-fixture use.
This Rheem is best viewed as a compact, efficient solution rather than a high-capacity workhorse. If your project calls for dependable hot water at a sink, small office, or other low-demand location, it offers the right mix of size, controls, and efficiency.
Best with Extra Features – 36kW Electric Tankless Water Heater
If you need one of the most powerful commercial electric tankless water heaters for a larger home, this 36kW model is built for serious demand. It supports up to 8.7 GPM, uses self-modulating technology to steady water temperature, and is designed for whole-house hot water in homes with multiple bathrooms.
Best For: Large homes needing a high-output electric tankless unit with smart remote control and whole-house coverage.
Pros:
- Up to 8.7 GPM for broad household hot water demand
- Self-modulating output helps maintain stable temperature and improve efficiency
- Built-in WiFi lets you control temperature from your smartphone
- ETL certified with leakage, overheat, and dry-fire protection
Cons:
- Requires a 300A household electrical service recommendation
- Needs 4 x 40A double-pole breakers and 4 x 8/2 AWG cables with ground
- Best suited to homes that can support a high-capacity 240V setup
This is a strong fit when you want maximum electric output, but it is not a casual plug-and-play choice. Verify electrical capacity first, then the compact wall-mounted design and remote controls make it a practical whole-home option.
Compact Sink-and-Shower Option – 14kW Electric Tankless Water Heater
For smaller installs, this 14kW model is a practical entry in commercial electric tankless water heaters. It is aimed at sink and shower use, offers instant heating with up to 99.8% efficiency, and keeps the footprint small for under-sink or wall mounting.
Best For: Compact spaces and lighter-demand applications with one or two hot-water points.
Pros:
- Instant heating with no standby energy loss
- LED display shows inlet/outlet temperature, GPM, and kW
- Precise 1°F temperature control from 86°F to 131°F
- Fast installation-friendly design with wiring access that avoids housing disassembly
Cons:
- 14kW output is intended for lighter hot water demand
- Requires a 60-amp circuit breaker
- 3.3 GPM max flow is not aimed at larger multi-fixture homes
This model makes sense when space is tight and you want efficient point-of-use performance. It delivers the most value where hot water demand is modest rather than whole-house heavy-duty use.
Medium-Capacity Space Saver – 18kW Electric Tankless Water Heater
This 18kW unit sits in a useful middle ground among commercial electric tankless water heaters for apartments, salons, garages, and medium homes. It delivers up to 4.9 GPM, supports 2-3 simultaneous water needs, and uses smart adaptive heating to hold a steady temperature.
Best For: Apartments, condos, and medium-size households needing reliable 2-3 point hot water coverage.
Pros:
- Up to 4.9 GPM for multiple fixtures
- Ultra-thin wall-mount design saves space
- Temperature range from 77°F to 140°F in 1°F steps
- 8-layer safety system with leakage, grounding, and fault diagnosis protection
Cons:
- Requires professional electrical setup and capacity verification
- Needs 2 x 40A double-pole breakers and 2 x 8 AWG/2 wires with ground
- Less output than larger whole-house units
For buyers who want more capacity than a small point-of-use heater but do not need a massive whole-home system, this is a balanced choice. The combination of compact size, solid flow rate, and layered safety features makes it easy to justify for everyday multi-fixture use.
How We Picked These Commercial Electric Tankless Water Heaters
We focused on practical business-use factors: heating power, supported flow rate, temperature control, electrical requirements, certification, and how well each unit fits small- to medium-demand commercial setups. We also favored models with clear spec sheets and features that help with everyday operation, such as self-modulating output, digital controls, and compact footprints.
Quick Comparison: What Matters Most
The biggest difference between Commercial Electric Tankless Water Heaters is not just size, but usable capacity. Higher-kW units are better for multiple fixtures or higher temperature rise, while lower-kW models fit hand-wash stations, breakrooms, and light-duty applications. If you expect simultaneous demand, prioritize flow rate and amperage requirements first, then compare temperature control and installation space.
Key Buying Factors for Commercial Electric Tankless Water Heaters
Electrical Capacity
Confirm voltage, breaker requirements, and available amperage before buying. Many higher-output units require substantial service capacity, and underpowered electrical supply will limit performance regardless of the heater’s advertised output.
Flow Rate and Temperature Rise
Look for a heater that can maintain target temperature at your expected incoming water temperature and peak fixture demand. A unit that performs well in warm climates may struggle in colder regions if the temperature rise is too high.
Installation Location
Commercial spaces often benefit from compact wall-mounted units near the point of use. Shorter pipe runs can improve response time and reduce wasted water while helping the system deliver more consistent hot water.
Controls and Efficiency
Features like self-modulating heating, digital temperature adjustment, and real-time display readouts can improve comfort and reduce energy waste. For businesses that use hot water throughout the day, these controls can make a noticeable difference in operating cost.
Who Should Buy Which Commercial Electric Tankless Water Heaters?
Choose a lower-kW model for light commercial use such as restrooms, offices, and sink-only stations. Step up to mid-range units for salons, small food prep areas, and two-fixture needs. Select higher-output Commercial Electric Tankless Water Heaters for multi-point hot water demand, larger facilities, or setups where several users may draw hot water at once.
If you are unsure, size for your peak load rather than your average day. That approach reduces the risk of lukewarm water complaints and helps ensure the system remains useful as your business grows.
