If you’re looking to supply endless hot water to a large home with multiple bathrooms, a tankless water heater is the way to go. But not all tankless water heaters are built the same, and larger homes require units with high flow rates (GPM), energy efficiency, and the ability to handle multiple fixtures simultaneously.
Based on my experience with installations in large homes, here’s a breakdown of the best tankless water heaters that will keep the hot water flowing without interruption.
Top 4 Best Tankless Water Heaters for Large Homes
| Heater Name | Max GPM | Efficiency (%) | Fuel Type | Best For | Price Range |
|---|---|---|---|---|---|
| Rinnai RUR199iN | 11 GPM | 96% (Condensing) | Natural Gas | Large homes, multiple fixtures, recirculation | $$$$$ |
| Noritz NRC1111-DV | 11.1 GPM | 94% (Condensing) | Natural Gas | High-demand homes, cold climates | $$$$ |
| Navien NPE-240A2 | 11.2 GPM | 98% (Condensing) | Natural Gas/Propane | Recirculation, instant hot water, large homes | $$$$$ |
| Stiebel Eltron Tempra 36 Plus | 7.5 GPM | 99% | Electric | Large homes, eco-friendly, high efficiency | $$$ |
1. Rinnai RUR199iN – Best Overall Tankless Water Heater for Large Homes
The Rinnai RUR199iN is one of the best choices for large homes with high hot water demand. This natural gas unit provides up to 11 GPM, making it ideal for running multiple showers, dishwashers, and washing machines simultaneously.
Key Features:
- Max GPM: Delivers up to 11 GPM, ideal for 4+ bathrooms.
- Efficiency: 96% thermal efficiency with condensing technology, which recycles exhaust heat for maximum energy savings.
- Built-in Recirculation Pump: The integrated recirculation pump reduces wait times for hot water, especially for fixtures far from the unit.
- Wi-Fi Compatibility: Connects with Rinnai’s Control-R™ module for remote control and monitoring of the water heater via smartphone.
- Dual Venting Options: Flexible venting options (concentric or twin-pipe) make installation easier.
Best For:
- Large homes with multiple bathrooms and high hot water demands.
- Homeowners who want instant hot water with recirculation.
- People looking for premium features and top-tier efficiency.
Pros:
- High GPM—can handle multiple fixtures simultaneously.
- Recirculation pump ensures instant hot water, reducing water waste.
- Wi-Fi compatible for remote scheduling and control.
- Condensing technology for superior energy efficiency.
Cons:
- Higher upfront cost, but it pays off in energy savings over time.
- Requires professional installation for venting and gas setup.
2. Noritz NRC1111-DV – Best for Cold Climates and High Demand
If you live in a cold climate and need to run multiple fixtures at once, the Noritz NRC1111-DV is one of the best choices. It offers 11.1 GPM, making it perfect for homes with multiple showers and appliances running simultaneously. The condensing technology ensures energy efficiency even in high-demand situations.
Key Features:
- Max GPM: Provides up to 11.1 GPM, ideal for homes with 4-5 bathrooms.
- Efficiency: 94% efficiency with condensing technology, saving energy by reusing heat from the exhaust gases.
- Durability: Built with stainless steel heat exchangers for longer life and better resistance to corrosion.
- Low NOx Emissions: Complies with low-NOx emissions standards, making it eco-friendly.
- Advanced Temperature Control: Precise temperature control for consistent hot water output, even in colder climates.
Best For:
- Homes in cold climates where incoming water temperatures are low.
- Large families or households with high hot water usage.
- Eco-conscious homeowners who need energy efficiency and low emissions.
Pros:
- High GPM, perfect for large homes with multiple fixtures.
- Condensing technology for excellent energy savings.
- Stainless steel heat exchangers ensure long-term durability.
- Complies with low-NOx emission standards for eco-friendly operation.
Cons:
- High cost for installation, but worth it for large homes in colder regions.
- Requires professional installation due to gas and venting setup.
3. Navien NPE-240A2 – Best with Recirculation for Instant Hot Water
The Navien NPE-240A2 is a top choice for homeowners who need instant hot water and high GPM. This model comes with a built-in recirculation pump, ensuring hot water is available immediately at all fixtures, reducing water waste and wait times. It can handle large households with ease, thanks to its 11.2 GPM capacity.
Key Features:
- Max GPM: Offers up to 11.2 GPM, perfect for 4+ bathrooms.
- Efficiency: 98% efficiency due to its condensing design, making it one of the most energy-efficient models on the market.
- Built-in Recirculation Pump: The ComfortFlow™ recirculation system ensures hot water is delivered quickly, especially in homes with long pipe runs.
- Wi-Fi Compatible: Works with Navien’s NaviLink™ system, allowing for remote control and diagnostics via smartphone.
- Dual Stainless Steel Heat Exchangers: Offers superior durability and corrosion resistance.
Best For:
- Large homes needing instant hot water throughout the house.
- Homeowners looking to minimize water waste with a built-in recirculation system.
- Households that need high GPM and premium energy efficiency.
Pros:
- High GPM—perfect for large homes with heavy hot water demand.
- Recirculation system provides immediate hot water.
- 98% efficiency, saving on energy bills over time.
- Wi-Fi compatible for remote operation.
Cons:
- Expensive upfront, but the efficiency and recirculation make it worth the cost.
- Requires professional installation, especially for the recirculation setup.
4. Stiebel Eltron Tempra 36 Plus – Best Electric Tankless Water Heater for Large Homes
For those looking for an electric option, the Stiebel Eltron Tempra 36 Plus is one of the most powerful and efficient electric tankless water heaters on the market. With 7.5 GPM, it’s great for large homes that want to avoid gas lines while still getting a reliable flow of hot water.
Key Features:
- Max GPM: Provides 7.5 GPM, which can support 2-3 bathrooms running simultaneously.
- Efficiency: 99% energy-efficient, making it one of the most eco-friendly options, with no standby heat loss.
- Advanced Flow Control™: Automatically adjusts the flow of water to maintain consistent temperatures, even when demand fluctuates.
- Digital Temperature Control: Allows precise temperature settings in 1-degree increments.
- No Venting Required: Since it’s electric, installation is much simpler and doesn’t require venting.
Best For:
- Homes that prefer electric water heating and don’t want the hassle of gas lines.
- Large homes with moderate hot water demand where 7-8 GPM is sufficient.
- Eco-conscious homeowners looking for energy efficiency.
Pros:
- 99% efficiency—saves significantly on energy costs.
- No venting required, making installation easier.
- Advanced flow control ensures consistent hot water output.
- Ideal for homes without access to gas.
Cons:
- Lower GPM compared to gas units—may not meet the needs of very large homes.
- Requires a high electrical load, so make sure your home’s panel can handle it.
Key Factors to Consider When Choosing a Tankless Water Heater for Large Homes
1. Flow Rate (GPM)
- GPM (Gallons Per Minute) is the most important metric when choosing a tankless water heater for a large home. You’ll need at least 8-11 GPM to ensure you can run multiple showers, appliances, and fixtures at once.
- For homes with 4-5 bathrooms, aim for 10-11 GPM to cover high demand.
2. Fuel Type: Gas vs. Electric
- Natural gas or propane tankless water heaters generally offer higher GPM than electric models, making them better for large homes with high water demand.
- Electric tankless heaters like the Stiebel Eltron Tempra 36 Plus are highly efficient but may not provide as high of a flow rate as gas.