Wiring in a hot water heater

[Edwardrudd]

I've got a 2016 Jayco eagle 5th wheel and I them put in a tankless water heater but it keeps freezing up on us so I hired a handyman to take it out and put the other one back in problem is he didn't mark the wiring now I need to know how to wire it up can someone help me with the wiring just tell me what wire goes to what wire thank you

[360Bridges]

Can you email Jayco, get wiring schematics from them? Perhaps Im misunderstanding... Good Luck!