Tankless water heaters have a built in regulator that’s going to slow down the flow of the hot water in your RV. The hotter you want your water, the slower the flow rate of your water is going to be. This is so the water can spend more time getting spun around that hot core and get more time to heat up. For a Gerard tankless water heater, you usually gonna get a flow rate of around 1.2 gallons per minute and for a Furrion water heater usually gonna get a flow rate of around 2.4 gallons per minut