Hi Shelly,
H'mm you said the fridge is running, that sounds like maybe someone replaced the original RV fridge with a compressor one. An RV fridge makes no noise at all other than the sound of slight expanding metal when the burner tube heats up.
Question: Do you have a 12 volt battery installed in the camper and is it charged up? It would be out front by the LP tanks.
What you described working seems to point to only 120 VAC things that is unless you actually have a RV fridge. The lights are on 12 volts DC and run off the battery and the power converter. That is unless someone converted something.
Does the vent fan in the bath room, the vent fan in the range hood or the water pump work? They are all on 12 VDC. If they work and the lights do not, then it might be a fuse is blown. Need to find the fuse panel. Look where the outside power cord comes into the camper. On the inside the power converter and fuse panel should be close by.
Hope this helps and good luck.
And Welcome to Sunline Owners club and congrats on your new coach!
John
Ps you asked about a new Hot water heater, See here for one place that sells them.
Atwood RV Water Heaters - PPL Motor Homes
A 6 gallon HW heater can range from $268 to $340 pending if it has the electric option. If you need more help on this try and post the model and serial number of the one you have and we can look it up to help better. Your age camper may only have had the gas option.
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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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