10 Best Tankless Rv Water Heaters 2025 in the United States

The Fogatti RV Tankless Water Heater is designed specifically for RV users looking for reliable and efficient hot water on the go. It offers a strong flow rate of up to 3.6 gallons per minute, which is enough to comfortably supply hot water to both bathroom and kitchen at the same time without long waiting times. Its 66,000 BTU output ensures quick heating even in colder conditions or higher altitudes, supported by its advanced heat exchange system and weather-resistant build. The unit uses propane fuel, which is common for RV appliances and allows for energy-efficient operation, especially thanks to its ultra-low 0.5 GPM flow startup that saves fuel during low-demand use.

Temperature control is a standout feature here, maintaining water temperature within a tight ±1°F range and adapting flame intensity by season to avoid overheating or under-heating. The built-in mixing tank further smooths out sudden temperature changes, increasing comfort during showers. At 15 by 15 inches and weighing about 34 pounds, it strikes a good balance between compact size and power, making it practical for RV installation. It includes thoughtful extras like a pressure relief valve and remote control for convenience and safety, plus protective features against freezing, flame failure, and oxygen depletion.

Some users might find installation requires professional help if they aren’t comfortable with propane connections and venting. Also, while efficient, the 3.6 GPM flow might be limiting if multiple high-demand appliances run simultaneously. This water heater is well suited for RVers wanting consistent, energy-efficient hot water with good temperature stability and durability for everyday use and varying weather conditions.

The FOGATTI InstaShower 8 Plus is a strong choice for RV owners looking for a reliable tankless water heater. It runs on propane, which is convenient for RVs since it doesn't rely on electricity, making it dependable during camping trips. It delivers a good flow rate of up to 2.9 gallons per minute, meaning you get nearly continuous hot water without the wait or limits of traditional tank heaters. Its 55,000 BTU output ensures the water heats quickly, even at high altitudes like Denver’s 9,800 feet, thanks to a special high altitude mode. The heater is fairly compact and weighs about 30 pounds, with a 15x15 inch door size designed to fit many existing RV setups, making replacement or upgrades easier. It also includes useful safety features such as anti-freeze protection, overheat protection, and automatic gas shut-off, adding peace of mind. The included remote controller helps with easy temperature adjustments.

With a decent energy efficiency rating of 84%, it manages propane use effectively, helping save on fuel during travel. Installation seems straightforward if your RV matches the door size, and the built-in pressure relief valve reduces extra parts to buy and install. One thing to note is that it may require door modifications for larger tank replacements. Also, while it’s safe and reliable, the product’s weight and size might be a consideration if space is very tight in your RV. For everyday RV use, especially in varying altitudes, this heater offers a good balance of performance, convenience, and safety.

The GIRARD Tankless RV Water Heater stands out with its powerful performance, delivering 42,000 BTUs, which means you can always expect a steady supply of hot water in your RV. The 12V power operation and quiet, brushless motor ensure that it runs smoothly and quietly, which is great for a comfortable RV experience. Additionally, it is lightweight at 22 pounds and has compact dimensions (12.5"W x 12.5"H), making it a practical choice for the confined spaces of an RV.

The onboard microprocessor is a smart feature that helps regulate water temperature and flow, preventing fluctuations and ensuring safety from cold spots or scalding water. This product also boasts high energy efficiency, using only half the LP gas compared to traditional six-gallon tank water heaters, which can lead to significant savings over time. The digital user control panel adds convenience, allowing you to easily adjust temperature settings, switch between Fahrenheit and Celsius, and troubleshoot with error codes.

While the installation is designed to be straightforward, professional installation is strongly recommended, which might add to initial costs. Nonetheless, its freeze protection feature is a notable advantage for varying weather conditions. On the downside, it might be a bit more expensive upfront compared to traditional water heaters, and the requirement for professional installation could be a drawback for DIY enthusiasts. This tankless water heater is best suited for RV owners looking for a reliable, efficient, and high-performing solution for their hot water needs.