We had some of the same problems as the others.
We had to call the maker of the water heater to get some advice. The main thing is to bleed all water lines of air. Both city water and water you carry on board. I suggest you call them because there are other things that can be done if you are still having problems. After learning some of the tricks ours works fine.
The fender well skirts don't match up when closed on the two living room slides. That seems to be something we will have to live with.
The trim band that covers the joint between the bonded sides "tan part" and the thin metal skirt "brown part" began to pop loose. These are to different materials that expand and contract at different rates. Bay Hill allowed a non evergreen repair facility to do the work. All is well.
The handle on the kitchen faucet fell off. Had to tighten the set screw.
We had a leek under the kitchen sink. Had to replace two gaskets on the trap.
Be sure to check your Dometic awning for a recall. Just google Dometic awning recall and see what pops up. Follow directions to see if yours is affected. Ours was. They sent some to us. 1/2 hour later it was fixed.
I had good luck working with Evergreen and a man named Rod Batts <email@example.com>. He was able to answer many questions and expedite the repair of our band poping problem.
All this being said I don't think that any RV is going to be problem free right out of the box. Expect something. Just pack a tool box, work though a few kinks and enjoy.
Oh as far as the hood vent thing is concerned We always BBQ. The only time the vent has been turned on was during our walk through.
We love our Bay Hill. It is a great 5th wheel. Many good time ahead.
Chris and Judy