Just warm water. Fixed (in under an hour.) WOW you guys.

Glad you found the source of hot/cold mixing.

It is a 10 gallon Suburban HWH that is only ran on electric. The gas portion no longer functions (too much salt air.)

Maintenance has always been done for the last three years

Then gas side should be working. Have you done any troubleshooting?

One of the things nice about Suburban is the separate systems/controls.
Electric side doesn't work then you have gas side or vice versa
Atwood.....use same t-stats and controls....one not working could mean other not working.