Hum water heater not working on either Lp or electric.

My last water heater looked like that with the black box but my dometic heater has no such box and yep it’s full of water and lord I wished it was hot ?? no clicking when I turn the water heater on Lp. And no power to electric element either. Somehow my rv does not recognize I have a water heater ??

Jimbo

And nothing is burned either it’s a new rv 4 months old