Thanks for the input. Everything in this rig is original (from 1996), and could use updating. Eventually we will replace it all, but finances dictate doing it systematically. We are full time in our RV and are stationary at a campground. Right now the suburban furnace doesn't ignite, I'm assuming the orifice needs cleaned. Working on that tomorrow.
I've been doing quite a bit of research on the ventless wall units, and not seeing a problem, provided we open a window. I'm also trying to plan ahead provided we lose power.
Eventually we will most likely put in a new furnace,thanks alboy for the recommendation.