I got this Protium 16A smart switch to connect it to my water heater switch. I am not well-versed in wiring these switches, so I hired an electrician to wire them. He said there is no neutral wire connected directly to the heater plug from the switch box, but the wiring diagram says N-Out needs to connect to the heater plug's neutral. Can the common neutral wire be connected to N-in and N-out be left out? The electrician was clueless and didn't want to risk testing it out.