2017 Newmar Ventana LE Water Heater Switches

What do you mean you can "hear" it when connected to shore power? You mean the LP Gas burner flame you can hear? Or you hear a high pitched "whine"? If you mean the high Pitched Whine, that means the Water heater is on 120 volt and you have an Atwood brand Water heater. The LP will work when on 12 volt and both dry camp and Shore Power. There will be a red indicator light by the inside LP switch that will come ON when the flame fails to light. Really need a pic as most Water Heater switches(120 and LP) are located side by side. Also really need the Brand of Water Heater. Pics of the switches would also help. Doug

PS, the 2017 Spec sheet lists a SUBURBAN brand 120/LP water heater.
They also list an ON DEMAND Water Heater.