Yes, what were they thinking is right.
We have a heated underbelly to prevent the tanks from freezing which sounds nice at first, but it just dumps hot air into the underbelly space which ends up going straight out into the outdoors. As if that isn't bad enough, the air that is being blown outdoors has to be replaced inside an RV so you WILL get cold air drawn into it, no matter how hard to try to seal things up. Grrrr... We don't plan to camp in sub-freezing temps so I am going to disconnect the two ducts into the underbelly.