There should be a door on the outside allowing access to the element and thermostat. Square black cover maybe with vents? Where you drain the hot water. On the back.
2013 Jayco Eagle 328 RLTS
2021 Keystone Montana 3121RL
2013 F350 6.7L 4x4 CCLB
W/Air Lift air bags (front & rear)
Me, Momma and Charles (RIP buddy)
And introducing Sofie!! ;)