We are getting ready to take our Fifth Wheel on our first trip. I have a water inlet that says this on it: CAUTION SEWER TANK FLUSHER Sewer tank valves must be OPEN when using this inlet. OK...
The reason they say to keep the valve open is in case you have a case of CRS (can't Remember Stuff) and turn on the flusher, forget about it and then you get the gusher in the toilet and you know where that goes.