How do I increase the water temperature on my water heater?
How do I increase the water temperature on my water heater? Gas or electric water heaters Find the access panel for the thermostat(s) and use a screwdriver to remove the panel. Peel back the insulation. Use a flathead screwdriver to adjust the thermostat up or down. If your water heater has two thermostats, adjust both the same amount. What should the temp be on a Rinnai Water Heater? Our plumber installed a Rinnai high-efficiency tankless water heater, but the default maximum temperature was locked at 120 degrees. The manual was only sort of helpful, and there weren't any how-to tutorials...