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On your hot water heater, can you tell us a little about your camper?
Has the heater ever worked for you on electric? We do not know if you just bought the camper and trying to get the heater to work for the first time, or it was working and now stopped.
Odds are high there is a circuit breaker in the power converter panel that has a 15 amp breaker in it. The label on the diagram should call it out for the hot water heater. See if it is on or if it has tripped. This would prevent the electric element from working.
The model number you gave decodes to having direct spark ignition on the gas and it has the electric element. And it a rev 9 heater which means buried on the back of the heater is a small rocker switch that looks like this.
That little rocker switch needs to be on to allow the heater to work on electric. This was a pain to get to that switch as the heater is buried under couches, beds etc. What some folks did to get around this was to install a normal house looking switch remote somewhere to get to the switch easier.
It appears a prior owner did this in your case. That house type of big white rocker switch was not original from Sunline. That switch will also need to be on.
There is also the possibility the electric element has burnt out if all the switches and breakers are on. If someone by accident turned on the electric element with no water in the heater, the element will burn out in a few minutes or less as there is no water to cool the element. If this is the case, they are replaceable.
If this is the issue, Atwood part 92249 should be the screw in unit for your model number. There are many online places that sell them. Here is one https://www.amazon.com/Atwood-92249-...r+heater+parts
They also sell the wrench to put on the large nut to get it out. The element is in the back of the unit behind that little black rocker switch.
Hope this helps and let us know how you make out or if you need more help on this
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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