May have a bad heating element in water heater

[okievet]

2015 Forest River FLAGSTAFF V LITE 30WFKSS​

I am a newbie that left my heater on after disconnecting water. Now I'm not getting any heat... Is there a way to troubleshoot this thing to make sure its indeed the element? Also, I don't have any documents on this, which thing in this mess is the element?

edit: Also, are these elements standardized at all? How do you know which to get?

 

[TheLooks]

No heat from electric? Or propane? You need a volt meter first of all. Lets review. The black rectangle at top of the left side is the resetable thermostat and overtemp safety. Push in on the black circles to reset the pair of them. The black cover behind the gas orifice is the element. They are pretty much standard. The specs will be on the one you remove. Also behind the gas valve will be a switch that turns off 120 vac to the element. There is a circuit board in the back that turns on the gas or electric or both. It uses relays to do this. The system should try to light 3 times before going into lockout when gas is used. I have seen electric elements burn out quickly and I have seen them not be fazed by no water. Luck of the draw. To check the Thermostat and high temp cut out, you remove the rectangle cover and check for continuity of each. Turn off 120vac and ohm out the element under the lower cover and look for 10 or so ohms. Also check for voltage (be careful not to short the wire to ground) when the system is turned on at both switches and calling for heat. No voltage here will indicate bad board or thermostats tripped or bad. If the propane does not light that is a different set of issues.