ktmrfs wrote:
most remote hwh switches are 12V running to a relay that switches the 120V to the element. If it really is 120V to the switch it should be #12 romex wire and a UL listed wall switch or toggle rated for 120V and at least 15A.
….
here is a link to a typical suburban wiring diagram. Note NONE of the switches are 120V, they are ALL 12V.
The black switch on the front bottom left corner of a Suburban water heater is 120 VAC. If there is a switch inside the RV for operating the WH on electric it is a 12 VDC switch that activates an interposing relay to send 120 VAC to the switch on the water heater.
Look at figures 5b and 6b if there is an inside switch for operation on electric. The relay coil is shown in 5b. The relay contact and 120 VAC switch are shown in figure 6b.
Look at 5a and 6a if it does not have an inside switch for electric.
Suburban manual.