The Onsen 5L Outdoor Propane Portable Tankless Water Heater delivers instant hot water on demand, making it ideal for camping, hunting camps, off-grid cabins, boats, horse trailers, and other outdoor applications. Designed for heating typical summer water temperatures (around 60°F / 15°C and warmer), this lightweight unit is easy to transport, quick to set up, and perfect for temporary outdoor installations.

Fueled by propane, the Onsen 5L provides 32,000 BTU/hr of heating power, runs on a standard 20 lb BBQ propane tank, and can provide up to 16 hours of hot water runtime (usage varies by temperature settings, inlet water temperature, and flow rate).

Onsen 3.0 12V water pump (included): provides the water pressure required for the water heater to operate when a pressurized water source is not available. The pump produces 55 PSI of pressure and up to 3.0 GPM of flow, and features an automatic pressure switch that activates the pump when a faucet or showerhead is opened.
What’s included in this bundle

Onsen 5L Portable Tankless Water Heater

• Shower head with on/off control
• Gas regulator for 20-pound propane tank
• 12V alligator clips (for 12V ignition option)
• Quick-connect adapters for standard garden hose
• Teflon tape
• Hardware kit (mounting screws & anchors)

Onsen 3.0 RV Diaphragm 12V Water Pump

• Filter with 40 mesh stainless steel screen
• 2 x ½" hose barb adapters
• 2 x ½" threaded adapters
• 12V battery alligator clips (w/ 15A fuse)

Important notes

• For outdoor use only.
• Water pressure: requires a pressurized water source of 10 PSI or more. A compatible pump system is required when drawing water from a lake or tank.
• Water pump use: when using a pump, we recommend ½″ diameter hose from the water source to the pump and from the pump to the water heater. While most pumps provide sufficient PSI, ignition issues are often caused by incorrect hose diameter (e.g., 5/8″ or 3/4″).