Ok, todays project was connecting a Hotrod water heater. I had it on my old coach and pulled it off. They are only about $70 on amazon but I knew they wouldn't give me any extra for it and the new owner probably wouldn't know what the heck it was for anyway.
So all it is is a heating element that you remove your drain plug from the tank outside and this fits up into it. Run a couple wires inside and the control unit has double sided tape to stick it directly to the tank. Plug it in and turn on the switch and BAM!....wait an hour and you have hot water! LOL.
Now for the reasoning. Yes mine like yours came with an electric element to heat the water BUT it is not adjustable. I am sure we have all been either froze or scolded by the shower water when turning back on. This unit has thermostat that you can adjust from about 90*-125* or such. I play with it till I get the water between 99-102* then let it go. Now when we take a shower all you do is turn on the hot water valve because there is no danger of being scolded or froze, turn the button on the head off and when back on once again no worries about the temp. We find this saves quite a bit of water if dry camping in not wasting water trying to get the temp right.
Now to make this even MORE convenient, I disconnected the original heating element and ran those wires to receptacle end (like for an extension cord) outside of the little box they are mounted in obviously and plug in the new unit. Now when I turn on my electric element up on the panel beside the gas switch it turns on the heater.
I measured the currents, the original electric element would pull 11 amps, this one only pulls 3.4 amps but it also takes longer to heat the water. That isn't a problem for us because I take my shower at night and the wife takes hers in the morning so there is lots of time to recover the tank. This works really great for the ole Navy shower.
Here is a link for the camco unit http://www.amazon.com/Camco-11673-Wa...element+for+rv
this is the 6 gallon unit and there is also a 10 gallon unit available. Don't think any of the ACE's came with a 10 gallon tank though.