Nice looking camper and congrats to you!
The water heater bypass valve is a white valve on the back side bottom of the water heater tank. See the yellow arrow in this pic
When the lever handle is horizontal, like in the pic, that is the normal position to let water into the heater.
When the lever is vertical, pointing up, that is the bypassed position.
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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