Supplying consistent hot water for three bathrooms simultaneously requires a powerful and efficient electric tankless water heater with a high flow rate (GPM) to handle multiple showers and sinks running at once. Electric models are energy-efficient and space-saving, but you need to ensure they can meet your home’s hot water demands.
Here’s my list of the best electric tankless water heaters that can efficiently serve three bathrooms without running out of hot water, along with what makes each of them a great choice.
Top 3 Best Electric Tankless Water Heaters for 3 Bathrooms
| Heater Name | Max GPM | Power Rating | Efficiency (%) | Best For | Price Range |
|---|---|---|---|---|---|
| Stiebel Eltron Tempra 36 Plus | 7.5 GPM | 36 kW | 99% | Whole-house for 3-4 bathrooms, high efficiency | $$$$ |
| EcoSmart ECO 36 | 6.5 GPM | 36 kW | 99% | Whole-house, budget-friendly, 3 bathrooms | $$$ |
| Rheem RTEX-36 | 6.0 GPM | 36 kW | 99.8% | Whole-house, multiple simultaneous showers | $$$ |
1. Stiebel Eltron Tempra 36 Plus – Best Overall Electric Tankless Water Heater for 3 Bathrooms
The Stiebel Eltron Tempra 36 Plus is one of the most reliable and powerful electric tankless water heaters on the market. It’s designed for whole-house use and can easily support 3-4 bathrooms, making it perfect for homes with multiple showers running at the same time.
Key Features:
- Max GPM: Provides up to 7.5 GPM in ideal conditions, which can handle 3 simultaneous showers plus other fixtures like sinks or dishwashers in warm climates.
- Power Consumption: Uses 36 kW, so you’ll need adequate electrical capacity (150 amps).
- Advanced Flow Control™: Automatically adjusts water flow to maintain a consistent temperature when demand is high, preventing any sudden cold water surprises.
- Digital Temperature Control: Precise settings in 1-degree increments between 86°F and 140°F, ensuring perfect water temperature for every use.
- Efficiency: 99% efficiency, meaning almost all energy goes directly into heating water, saving you on electricity bills.
Best For:
- Large households with 3-4 bathrooms that require hot water at multiple fixtures simultaneously.
- Homeowners looking for a high-efficiency solution with consistent temperature control.
Pros:
- High flow rate (7.5 GPM), ideal for multiple showers.
- Advanced Flow Control ensures hot water for all fixtures, even when demand is high.
- Energy-efficient with 99% efficiency, cutting down on utility bills.
- Compact and sleek design, saving space compared to traditional water heaters.
Cons:
- Requires a high electrical capacity—ensure your home can handle the 36 kW draw with the proper breakers and wiring.
- Pricey upfront, but pays off in long-term savings on energy and water consumption.
2. EcoSmart ECO 36 – Best Budget-Friendly Option for 3 Bathrooms
The EcoSmart ECO 36 is a more affordable but still highly capable unit that works well for homes with 3 bathrooms. While it has a slightly lower flow rate than the Stiebel Eltron, it’s still powerful enough to handle multiple fixtures at once and provides excellent energy efficiency.
Key Features:
- Max GPM: Delivers 6.5 GPM, enough for 3 showers running at once in warmer climates. In colder areas, you may experience a reduction in flow rate, so it’s ideal for homes where water demand is high but the incoming water temperature is moderate.
- Power Consumption: Requires 36 kW and a 150-amp electrical service.
- Self-Modulating Technology: Automatically adjusts energy consumption based on hot water demand, improving efficiency and lowering energy bills.
- Digital Temperature Control: Allows precise temperature settings with 1-degree increments from 80°F to 140°F.
Best For:
- Budget-conscious homeowners who still need a tankless water heater that can support 3 bathrooms simultaneously.
- Mild to warm climates where incoming water is already warmer, allowing higher GPM.
Pros:
- Affordable compared to other high-capacity electric tankless models.
- Self-modulating technology improves energy efficiency and reduces power consumption.
- Compact design makes it easy to install in tight spaces.
Cons:
- Flow rate decreases significantly in colder climates.
- Requires 150-amp electrical service and may require panel upgrades in some homes.
3. Rheem RTEX-36 – Best for Multiple Simultaneous Showers
The Rheem RTEX-36 is another great choice for homes with 3 bathrooms. It has slightly lower GPM than the Stiebel Eltron but still delivers reliable hot water for multiple showers at once. Rheem’s tankless water heaters are known for their durability and efficiency, making the RTEX-36 a top pick for households with moderate to high hot water demand.
Key Features:
- Max GPM: Offers 6.0 GPM, enough for 2-3 showers running at once, depending on the climate. In warmer areas, you’ll get higher GPM.
- Power Consumption: Uses 36 kW and requires a 150-amp electrical service.
- Self-Modulating Power Control: Ensures energy efficiency by only using the electricity necessary to meet hot water demands.
- Durable Copper Immersion Heating Elements: Designed for longevity and field serviceable for easy maintenance.
- Digital Thermostat: Precise temperature control between 80°F and 140°F with LED display for easy adjustments.
Best For:
- Homes with 3 bathrooms needing hot water for multiple showers simultaneously.
- Homeowners looking for a durable and reliable electric tankless water heater.
Pros:
- Field-serviceable elements make maintenance easier and less expensive.
- Energy-efficient with self-modulating technology.
- Compact size allows for easy installation in small spaces.
- Simple digital control with precise temperature settings.
Cons:
- Lower GPM compared to other models on the list.
- Needs a 150-amp electrical panel.
Key Factors to Consider When Choosing an Electric Tankless Water Heater for 3 Bathrooms
1. Flow Rate (GPM)
- To run 3 bathrooms simultaneously, you’ll need at least 6-7 GPM. This will ensure multiple showers and faucets can run at the same time without dropping water temperature.
- Colder climates may reduce GPM due to lower incoming water temperature, so consider a higher GPM model if you live in an area with cold winters.
2. Power Consumption (kW)
- 36 kW is standard for high-capacity electric tankless water heaters that can serve multiple bathrooms. Ensure your home has the electrical capacity (usually requiring 150-amp service) to handle the load.
- You may need to upgrade your electrical panel if it doesn’t meet the required amperage for the unit.
3. Energy Efficiency
- All models listed are 99% efficient, which means almost all of the electricity used goes into heating the water. This helps save on your energy bills and reduces your environmental footprint.
4. Climate
- Flow rate can drop significantly in cold climates. If you live in a region with cold winters, the GPM might be lower than the listed max. In these cases, consider a higher GPM unit to ensure you have enough hot water capacity year-round.
Pros and Cons of Electric Tankless Water Heaters for 3 Bathrooms
| Pros | Cons |
|---|---|
| Endless hot water—never run out of hot water | Requires adequate electrical capacity |
| Energy-efficient—saves on utility bills | GPM may drop in cold climates |
| Compact and space-saving | Higher upfront cost than traditional water heaters |
| Precise temperature control | May require electrical panel upgrades for 36 kW units |
Conclusion: Which Electric Tankless Water Heater is Best for 3 Bathrooms?
- For best overall performance, the Stiebel Eltron Tempra 36 Plus offers the highest flow rate, advanced flow control, and energy efficiency, making it perfect for handling 3 bathrooms simultaneously.
- For a more budget-friendly option, the EcoSmart ECO 36 provides solid performance at a lower cost, though it may struggle in colder climates.
- If you want reliable performance with easy maintenance, the Rheem RTEX-36 is a great choice, offering field-serviceable elements and precise digital control.
Any of these options will provide consistent hot water and energy savings, keeping your home comfortable and efficient!