If you’re looking to provide on-demand hot water for a single bathroom, you’ll want a compact, efficient electric tankless water heater with a moderate flow rate (GPM) that can comfortably handle a shower and sink without overloading your electrical system. The key is to find a model that strikes the right balance between size, efficiency, and flow rate to meet the hot water needs of one bathroom.
Here’s my guide to the best electric tankless water heaters for a single bathroom, based on performance, energy efficiency, and ease of installation.
Top 3 Best Electric Tankless Water Heaters for One Bathroom
| Heater Name | Max GPM | Power Rating | Efficiency (%) | Best For | Price Range |
|---|---|---|---|---|---|
| Stiebel Eltron DHC-E 12 | 1.5-2.0 GPM | 12 kW | 99% | Point-of-use, single bathroom, compact | $$ |
| EcoSmart ECO 11 | 1.3-2.0 GPM | 13.3 kW | 99.8% | Small homes, point-of-use, single bathroom | $$ |
| Rheem RTEX-13 | 1.5 GPM | 13 kW | 99.8% | Single bathroom, low water demand | $$ |
1. Stiebel Eltron DHC-E 12 – Best Overall Electric Tankless Water Heater for One Bathroom
The Stiebel Eltron DHC-E 12 is a highly reliable, compact electric tankless water heater that’s perfect for a single bathroom or point-of-use applications. It provides instant hot water with advanced control and excellent energy efficiency.
Key Features:
- Max GPM: Delivers up to 1.5-2.0 GPM, ideal for a single shower and sink.
- Power Consumption: Draws 12 kW and requires a 240V/60 amp breaker.
- Digital Temperature Control: Provides precise temperature control with 1-degree increments, allowing you to set the water temperature between 86°F and 140°F.
- Efficiency: 99% energy efficiency, ensuring minimal heat loss and low operating costs.
- Flow Sensor: Automatically adjusts energy consumption based on water demand to maintain a consistent temperature, even with varying flow rates.
Best For:
- Homeowners needing a point-of-use tankless water heater for a single bathroom.
- Small spaces where a compact, wall-mounted unit is necessary.
- Efficient heating with precise temperature control.
Pros:
- Compact design perfect for installation near sinks or showers.
- High efficiency—saves energy and reduces utility costs.
- Easy installation with minimal space requirements.
- Digital temperature control ensures consistent water temperatures.
Cons:
- Lower GPM, so it’s limited to single-point use (not ideal for multiple fixtures at once).
- Best suited for moderate climates where incoming water temperatures aren’t too cold.
2. EcoSmart ECO 11 – Best for Budget-Friendly Efficiency
The EcoSmart ECO 11 is a great budget-friendly choice that delivers solid performance for a single bathroom. Its self-modulating technology makes it highly efficient, ensuring you only use energy when hot water is needed.
Key Features:
- Max GPM: Provides 1.3-2.0 GPM, perfect for a single shower or bathroom sink, especially in warmer climates.
- Power Consumption: Uses 13.3 kW and requires a 240V/60 amp breaker.
- Self-Modulating Technology: Adjusts power usage according to the water flow rate, ensuring energy savings.
- Temperature Control: Offers digital control to set water temperature in 1-degree increments between 80°F and 140°F.
Best For:
- Homeowners on a budget looking for an efficient solution for single bathroom use.
- Homes in warm climates where incoming water temperatures are not too low.
- Small spaces or apartment bathrooms where compact size is essential.
Pros:
- Affordable without sacrificing efficiency.
- Self-modulating technology improves energy savings and performance.
- Compact design allows for easy installation in tight spaces.
- Provides consistent hot water for a single fixture.
Cons:
- Flow rate drops in colder climates, so performance may be reduced in areas with cold incoming water.
- May struggle to handle multiple fixtures if needed (best for one shower or sink at a time).
3. Rheem RTEX-13 – Best for Low Water Demand
The Rheem RTEX-13 is a great option for low water demand applications, like a single bathroom. It’s compact, highly efficient, and designed for point-of-use installations. It’s perfect for moderate hot water needs, such as a single shower or bathroom sink.
Key Features:
- Max GPM: Delivers 1.5 GPM, ideal for one shower or sink running at a time.
- Power Consumption: Uses 13 kW and requires a 240V/60 amp breaker.
- Durable Copper Immersion Heating Elements: Designed for long-lasting performance and easy field servicing.
- Digital Thermostat: Provides precise temperature control between 80°F and 140°F with easy-to-read LED display.
Best For:
- Single-point use in a single bathroom where hot water demand is low.
- Homeowners looking for a reliable, simple installation with minimal maintenance.
- Small homes, apartments, or guest bathrooms.
Pros:
- Easy installation and compact design make it perfect for point-of-use.
- Energy-efficient with self-modulating technology to save on power bills.
- Durable components ensure long-lasting use and reliability.
- Precise temperature control for comfortable water temperatures.
Cons:
- Limited to one fixture at a time—not ideal for multi-fixture use.
- Lower flow rate, so it may not perform well in areas with cold incoming water.
Key Factors to Consider When Choosing an Electric Tankless Water Heater for One Bathroom
1. Flow Rate (GPM)
- To comfortably serve a single bathroom, you’ll want at least 1.5 GPM. This will provide enough hot water for a shower and sink, though not for multiple fixtures running simultaneously.
- Keep in mind that in cold climates, incoming water temperatures will reduce the GPM, so you may need a higher-rated unit in those regions.
2. Power Consumption (kW)
- Most electric tankless water heaters for single bathrooms will require 12-13 kW, drawing around 60 amps. Make sure your home’s electrical panel can support the required breaker size before installation.
3. Energy Efficiency
- All the units listed here are 99% efficient or higher, which means they convert nearly all electricity into hot water, minimizing energy waste and saving on utility bills.
- Look for self-modulating technology (like in the EcoSmart ECO 11) to adjust energy use based on demand, further improving efficiency.
4. Climate
- Warmer climates allow for better performance, as the incoming water temperature is higher, allowing the unit to heat more water at a higher GPM.
- In colder climates, the GPM may drop, so consider a slightly higher capacity unit if you’re in a cold region where the water needs more heating.
Pros and Cons of Electric Tankless Water Heaters for One Bathroom
| Pros | Cons |
|---|---|
| Endless hot water for one fixture | May not support multiple simultaneous fixtures |
| Energy-efficient—saves on electricity bills | Lower flow rate in colder climates |
| Compact and space-saving | Requires adequate electrical capacity |
| Precise temperature control | Flow rate drops if water demand exceeds capacity |
| Easy installation for point-of-use | Limited to single-point use |
Conclusion: Which Electric Tankless Water Heater is Best for One Bathroom?
- If you want the best overall performance, the Stiebel Eltron DHC-E 12 is the top choice, offering advanced control, high efficiency, and reliability for a single bathroom.
- For those on a budget, the EcoSmart ECO 11 provides solid performance with self-modulating technology, making it highly efficient and affordable.
- If you need a simple, reliable option for low water demand, the Rheem RTEX-13 delivers consistent hot water for single fixtures, with a focus on durability and easy maintenance.
All these models will provide endless hot water for your bathroom while keeping energy consumption low and saving space in your home.