First off, welcome to the club!
What year/model is your camper? That helps tell us some about which vintage camper your have.
Giving some generic help to your question, Sunline used the Atwood brand LP detectors on many (if not all) the Sunlines that had them. Some of the older Sunlines may not have had any. Not sure what model year they came to be.
Since yours has one, on the back side of the detector there should be 2 wires that supply 12 volt DC power to it. They were wired live to the power convertor with no on/off switch. When ever you have a battery hooked up, OR plugged into shore power, the LP detector had power to it.
I'm not sure what you unhooked and where. Try and describe what you did. If you unhooked the 2 wires on the back from the LP detector, it should stop making alarm sounds. Is it disconnected at the actual detector and still going off?
As a side topic, the LP detectors have a limited life. Depending on the brand and vintage, they can be only good for 5 to 7 years once you buy them. If yours is the original, in any Sunline, it is overdue to be changed out.
The latest Atwood model LP detector is Atwood number 36719. They are for sale online at many places and the prices range from $47 to $75 pending where you buy them. A local RV dealer may also have them.
Hope this helps
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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