I'm assuming you are still on the original Dometic T stat. The cover comes off like this. Just insert a standard blade screw driver and twist, it will come right off. You do not have to pry.
and looks like this under it.
On that older style T stat is is not that accurate. Temps can swing +- 3 degrees or more between turn on and shut off. I cannot remember if there is an adjustable heat antisipator setup or not like the older home units had. I'm guessing not for the cost the thing is worth.
I converted to a digital one for $20 out of Walmart. Works great and accurate to within 1 degree. I think it has a deg C mode too.
If your interested in the conversion several here have done it on the forum. Let us know we have several posts with many how too pics in it. I myself even have more pics of the entire conversion.
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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