10 Best Outdoor Propane Tankless Water Heater 2025 in the United States

The Rinnai RE199eP Non-Condensing Propane Tankless Water Heater is an efficient and powerful option for those needing an outdoor installation. With a flow rate of up to 7.6 GPM, it can handle multiple fixtures simultaneously, ensuring you never run out of hot water. This model is compact, comparable to the size of a small suitcase, making it portable and easy to install in various outdoor settings.

The 199,000 BTU rating ensures quick heating, and the energy-efficient design only heats water when necessary, conserving energy. It also features a handy LED display that provides service reminders and error codes, which can be very helpful for maintenance and troubleshooting. A significant strength is its durability, backed by a robust residential guarantee (15 years for the heat exchanger, 5 years for parts, and 1 year for labor). However, professional installation is recommended, which might add to the initial cost. Furthermore, while it offers WiFi control, this requires an additional Controlr module, which is not included. The heater's design also meets strict environmental standards, such as the South Coast Air Quality Management District NOx emission levels.

One potential drawback is its non-condensing nature, which might be less efficient in capturing and reusing heat compared to condensing models. Additionally, users should verify if this heater is suitable for their region based on ground water temperature. This unit is best suited for households looking for a reliable and energy-efficient outdoor water heating solution with high flow rates and modern features.

The Rheem RRTGH95DVLP3701178 is a robust choice for an outdoor propane tankless water heater, offering a high flow rate of up to 9.5 gallons per minute (GPM). This makes it capable of supplying hot water for multiple outlets simultaneously, which is great for larger households or homes with high hot water demands. With a powerful BTU rating of 199,900, it heats water efficiently and quickly. The unit also boasts a high energy efficiency of 0.93, meaning it’s designed to save on energy costs over time.

Temperature settings range from 100 to 140 degrees Fahrenheit, with a default setting at 120 degrees, providing flexibility based on your preferences. The electric ignition simplifies the startup process, making it easy to use. Additionally, the product includes several safety features like Hot Start Programming and Overheat Film Wrap to ensure safe operation. It also comes with excellent warranty coverage: 1 year for labor, 15 years for the heat exchanger, and 5 years for parts.

On the downside, the unit is relatively heavy at 59.9 pounds, which might make installation a bit cumbersome. Its dimensions (17.7 inches wide and 23.7 inches high) mean you’ll need a fair amount of space for wall mounting. While it’s not the most compact model on the market, its performance and efficiency can make up for that if space isn’t a primary concern. This water heater is best suited for larger homes needing reliable and efficient hot water supply.

The FOGATTI Propane Tankless Water Heater is designed for outdoor installation and offers an impressive flow rate of up to 5.1 gallons per minute (GPM). With a BTU rating of 120,000, this unit can efficiently supply hot water to multiple points in a household, making it ideal for families.

This tankless water heater stands out for its precise temperature control, capable of maintaining water temperature within a 1°F margin, which is beneficial throughout the year. Additionally, its compact size (23.9)