10 Best Rv Tankless Water Heaters 2025 in the United States

The 2025 GEN II Ranein On-Demand RV Tankless Water Heater offers a strong combination of power and convenience for RV users who need a dependable source of hot water. With a heating capacity of 65,000 BTU and a flow rate of up to 3.9 gallons per minute, it provides continuous hot water, making it ideal for full-time RVers or those who enjoy longer showers. The unit runs on 12V power, which suits typical RV electrical systems, and it is designed to work well even at high altitudes up to 9,800 feet—a plus for mountain travelers. Its thermostatic chamber keeps water temperature steady, so you won’t experience sudden cold or hot bursts during showers.

Installation is fairly straightforward, especially if replacing older RV water heaters from popular brands, though you may need to purchase a compatible door kit separately to fit your RV’s exterior. At 15 x 15 inches and 27.5 pounds, it’s compact and lightweight enough for most RV setups. Safety is well-addressed, with features like a built-in exhaust fan for safe combustion, an automatic gas shut-off if the flame goes out, and a freeze protection system that activates below 42.8°F—important for cold climates. The unit is CSA certified, reassuring users about its reliability and safety standards.

A minor drawback is that the door is not included, which adds a small extra step for installation. This heater is a solid choice for RV owners needing efficient, safe, and consistent hot water, especially those traveling in varying climates and altitudes.

The 2025 GEN II Ranein On-Demand 65,000 BTU RV Tankless Water Heater is a solid choice for RV owners who want a dependable source of continuous hot water. With a flow rate of up to 3.9 gallons per minute, it delivers enough hot water for showers without running out, which is great for full-time RVers or campers who enjoy longer showers. It runs on 12 volts and propane, making it compatible with most RV setups, and its design includes staged combustion to maintain temperatures from 95°F to 124°F. This helps prevent overheating in warm weather and saves propane on longer trips.

The unit is relatively compact at 15 by 15 inches and weighs about 27 pounds, fitting easily into typical RV water heater compartments, and it is designed as a straightforward replacement for many popular models, although a compatible door kit might need to be purchased separately. Temperature control is user-friendly via a multi-function remote that also shows helpful info like gas usage and water flow, plus it works well at high altitudes up to 9,800 feet.

Safety is well addressed with features like an automatic gas shut-off if the flame goes out, a built-in pressure relief valve, and an anti-freeze system that activates to protect the unit in cold weather. The need to buy the door kit separately if your existing door doesn't fit adds to the installation cost. This heater combines efficient performance with thoughtful safety and convenience features, making it a reliable option for those who want hot water on demand in their RVs.

The FOGATTI RV Tankless Water Heater, InstaShower 8 Plus, is designed with RV enthusiasts in mind, particularly benefiting those who travel to high altitudes. One of its standout features is its capability to function effectively at elevations up to 9,800 feet, which is a significant plus for campers heading to mountainous regions. With a flow rate of up to 2.9 gallons per minute and a powerful heat output of 55,000 BTU, it ensures an uninterrupted supply of hot water, allowing multiple users to shower without running out of hot water quickly—a common issue with traditional tank heaters.

Installation is straightforward, as it can replace various existing water heaters, making it a versatile choice for RV owners looking to upgrade. The inclusion of a pressure relief valve and a wired remote controller further adds convenience, allowing control from a distance.

On the safety front, being CSA certified, it features several protective measures including anti-freezing protection, overheat protection, and an automatic gas shut-off, enhancing user confidence during use. This makes it a reliable option for those concerned about safety while on the road. However, there are some considerations to keep in mind. While its performance is commendable at high altitudes, the reliance on propane means users need to manage fuel levels, which could be a hassle during long trips. Additionally, while it excels in continuous hot water supply, potential users should ensure their RV's plumbing can handle the maximum flow rate without issues.