Developed for the RV market, these heaters have been popular on boats as well.
Gas-fired instant water heaters eliminate the storage and energy loss of hot water, takes up far less room than a hot water tank,
20-liter water heaters are tested by a Norwegian boating magazine, translated and published by Isotherm, one of the companies tested. Tests include heat loss, heating speed, safety thermostat operations, and draining.
Portable 5-gallon water heater uses propane for heat and a rechargeable battery for its pump. Shower head and bulk propane adapter available.
Guaranteed not to rust or leak, these stainless heaters come in 8 vertical and 5 horizontal models from 5 to 45 gallons.