My Host Everest has a large Dometic 8.0 CF Fridge located directly in front of the cabover on the drivers side slideout. I do not notice any noise at all. Just came back from a 9 day camping trip on the Kenai river. I didn't even notice if there was an extra fan, no perceptible noise at all.
i have the same set-up with the fridge in the slide and it has taken me quite some time to stop the fan from vibrating. hopefully its solved. there is not a lot of room to mount it between the fridge and the sidewall and not a lot to screw into. i got it pretty tight at first but traveling over the road took care of that. this last fix i put 2in velcro and re-screwed it. i also put a wedge on the other side for the banging around. i was also told to watch out for the wires getting burned on the coils, so i also attached the to the sidewall also. good luck, i hope i've solved my problem and helped someone else out.
I wonder if the Norcold sourced fans are quieter and that's why we do not hear them? We know Host uses Dometic - What refrigerator brand does Lance use? Or are these fans installed by the TC manufacturer and not dependent of the model?
We have the fridge in the slide. The fan that was in there is 90mm box fan, and very noisy in our case. Talked to Host, they recommend taking it to the local dometic dealer.. Doing research online shows that they simply replace the fan with an identical fan, which also can be noisy.
So I order 2 of the silent computer 90mm box fans, pulled the old fan out, soldered the two new fans in place, and put them in.
We have a AF1150 with a full wall slide and have never noticed any unusually loud noise from the fridge. In fact, I'd say ours is pretty quite to the point of not even being noticed.
With the refer in the slide you don't get a refer roof vent, so that is why they need a fan, can't work as good as the natural flow of hot air up and out the roof