Originally Posted by Sardis22
This my be a dum question but had to ask. How come all the plumbing fixtures in a rv have traps just like a house except the toilet. I would like to install a real toilet like in my house. Has anyone ever seen this. It would be great no smell.
I don't know what brand or model toilet you currently have, but Thetford makes several china RV toilets. I believe this is the one we have in our 2013 Adventurer.
Aqua Magic Residence
The big difference between RV toilets and residential ones are the amount of water needed to flush, the lack of a P trap in the RV style, and the fact that the residential style needs water standing in the bowl to provide a seal to the black water tank.
Beyond that the residential styles use a minimum of 1 gallon of water per flush. It wouldn't take long to empty a fresh water tank and fill the black water tank. There is no safety feature that would stop water from comming into the black water tank even though it's full. Given that most fresh water tanks are sized to be slightly smaller than the total volume of the grey and black water tanks, there's a good possibility you could have an overflow.
As mentioned earlier a gallon or more of water sloshing around in the toilet while traveling could create quite a mess. Then there's always the possibility that air rushing over the vent stack could create a venturi effect and pull the water in the bowl into the black water tank. If that happens you're in for a real treat when you open the bathroom door.
If you just want the look and feel of a residential toilet check out the Thetfords at your local RV dealer or Camping world. I don't think you'll be able to test them in the store so you'll have to go with whatever looks best.