Your 25' has a larger fridge than your 19', and a microwave over the fridge so needs an upper side vent door to let the warm air out the side. The fan helps move the air out, because it naturally wants to rise up, not sideways.
We have a street side awning to shade it, looking to park it so the vents are on the shady side when there is a choice. I also made simple props to hold the fridge vent doors open in warm weather because the furnished slots are too small. And I installed a simple inline lamp switch to shut the fan off if it seems to be running when we don't need it, but I think you have to be careful the compartment doesn't overheat.
I think you need to keep an eye on fridge compartment overheating no matter how it's vented, naturally or with a fan.
It's one of those things where you trade a convenient convection microwave location for natural fridge venting, and learn to handle it. Many folks have installed quieter fans but we haven't yet.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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