10 Best Tankless Gas Water Heaters 2025 in the United States

The Rheem RTGH-95DVLN-3 is a strong contender in the tankless gas water heater category. With a flow rate of up to 9.5 gallons per minute (GPM) and a BTU rating of 199,900, it’s capable of supplying hot water for multiple outlets simultaneously, making it ideal for larger households. Its energy efficiency rating of 0.93 means you can expect decent savings on energy bills, which is a big plus for budget-conscious consumers. Additionally, the unit features an integrated digital display that allows for easy temperature adjustments, ranging from 100 to 140°F, catering to various user preferences.

The compact design—measuring 17.7" wide and 23.7" high—makes it suitable for installations in smaller spaces, while the electric ignition simplifies startup. The manufacturer also offers a solid warranty: 1 year for labor, 15 years for the heat exchanger, and 5 years on parts, providing peace of mind for your investment.

However, there are some considerations to keep in mind. The venting requirements may necessitate additional installation work, particularly if your home isn't already set up for it, which could add extra costs. Furthermore, while its high flow rate is impressive, actual performance can vary based on incoming water temperature and other factors; thus, customers in colder climates might experience lower output.

The Rheem RTG-70DVLN-3 is an indoor tankless natural gas water heater designed to deliver continuous hot water with a maximum flow rate of 7 gallons per minute. This capacity allows it to support multiple simultaneous water uses, such as running a shower and dishwasher together, making it suitable for medium to larger households. It features an energy efficiency rating of 0.82, helping reduce gas consumption by heating water only when needed, which can lower energy bills. The unit includes hot-start programming to prevent cold water bursts, enhancing user comfort.

A notable feature is the LeakGuard system, which detects and prevents leaks to protect your home from potential water damage. Its compact dimensions (approximately 13.5 inches wide and 24.2 inches tall) and universal venting compatibility allow for flexible installation in various indoor spaces. While the 7 GPM flow rate meets the needs of most homes, households with very high water demand may require a higher capacity model. Being a non-condensing unit, it may have lower efficiency compared to condensing alternatives in certain climates.

The maximum water temperature reaches up to 140°F, which is adequate for most applications but should be considered based on individual preferences. This Rheem model offers a balance of solid performance, energy savings, and safety features, making it a practical choice for homeowners seeking reliable on-demand hot water without the size of a traditional tank.

The FOGATTI Natural Gas Tankless Water Heater is designed to deliver strong performance in a compact indoor unit, making it a good choice for households that need simultaneous hot water supply to multiple points like showers and sinks. It offers a high flow rate of up to 7.5 gallons per minute (GPM), which means it can handle several uses at once without running out of hot water. Its powerful 170,000 BTU rating supports quick heating, ensuring instant hot water, which is great for busy families or multitasking use. The unit features precise temperature control that keeps water temperature steady within about 1 degree, so you won’t experience sudden hot or cold bursts.

The heater is compact, taking up significantly less space than traditional tanks, and is relatively easy to install indoors, working with lower water pressures down to 15 PSI which is helpful for homes with weaker water systems. It runs on natural gas and requires standard 120V power for controls. The unit is made with durable materials like copper and stainless steel, backed by CSA certification and safety features, which adds to its reliability and longevity. It also includes a 2-year full warranty and 5 years on the heat exchanger, giving some peace of mind for maintenance.

This model is recommended for use below 2000 feet altitude and needs draining if unused in freezing temperatures to prevent damage, making it best suited for typical indoor environments without extreme cold exposure. Its energy efficiency and space-saving design are advantageous; however, installation must meet venting requirements for gas models, which might require professional help. This model is well suited for homeowners seeking a high-capacity, space-saving tankless water heater that provides steady, on-demand hot water for multiple points in the house.