10 Best Tankless Gas Water Heaters 2025 in the United States

The Rinnai RXP199iN tankless water heater offers a notable blend of versatility and efficiency. Its capacity to deliver up to 11.1 GPM makes it suitable for households with high hot water demands, potentially serving up to seven fixtures simultaneously. This high flow rate, coupled with a substantial 199,000 BTU rating, ensures a consistent supply of hot water even during peak usage times. The energy efficiency factor (UEF) of .98 indicates the unit is highly efficient, contributing to lower energy bills over time and making it an eco-friendly choice.

The Rinnai RXP160iN is a versatile tankless gas water heater that can run on either natural gas or propane, suitable for both indoor and outdoor installation with the proper venting. It delivers up to 9 gallons per minute, comfortably supplying hot water to multiple fixtures simultaneously—a good flow rate for medium to large households. Its energy efficiency is excellent, with a UEF rating of 0.97, which helps save on energy costs compared to traditional tank water heaters. The 160,000 BTU output ensures strong heating power, capable of maintaining a high temperature rise even if incoming water is quite cold.

The Rinnai RX160iN is a versatile tankless gas water heater suitable for both indoor and outdoor use, thanks to its Versa Vent system. It runs on natural gas or propane, offering flexibility depending on your fuel source. With a maximum flow rate of 9 gallons per minute, it can comfortably supply hot water to around six fixtures simultaneously, making it a good fit for medium to larger households. The unit boasts a strong 160,000 BTU rating, which supports a high temperature rise, so you can expect consistent hot water even in colder climates or when multiple taps are in use.