The Tank › Rheem tankless gas water heater always starts on HIGH! › Reply To: Rheem tankless gas water heater always starts on HIGH!
Hi: You might run this dip switch question by the installer, who should have a service manual for the heater. Other thoughts that come to mind are to add an expansion tank just upstream of the heater, so using cold water is less likely to reduce pressure in the hot side of things. Also, can a brace be added to the heater door to stop the banging? 😉