To add to what BenB stated, the single hung, up and down lifting windows, in your camper that is the 2 in the bedroom and the 1, bath window, dirt gets stuck in the slide tracks if the window has not been opened in a while.
To unstick, a stuck up and down window, lift the bottom screen up, way up, it slides up, and spray liquid silicone spray in the channel the window slides in. Do the bottom and sides of the channel up to the lifted screen.
Then so as Ben said, pull the 2 plunger levers towards the center and, yank the window up. Sometimes pushing down and then up constantly helps giggle it loose.
If you want to take the screen out, it is spring loaded on one side. Slide the screen up about 2" to 3" so the curved bottom corners come up out of the bottom track. Then push the screen frame to the side, one side is rigid, the other is spring loaded. The rigid side will not move at all, the spring side will allow the screen to compress and you can pull out the rigid side from the track.
Taking the screen out helps sometimes on real stuck windows to get the silicone spray into the channels better.
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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