Issue w/black water tank

[RachH]

Hello all!


I have a 2017 Keystone Avalanche 300RE and I am on 'city water fill' and shore electric. I have continually had issues with my black water tank since buying it used a few months ago.



- It fills up really fast and it's just me using it (not using toilet paper)

- It burps even when it was just dumped
- The sensors never show empty (not even close) and it's been flushed with chemicals, driven around with ice in the tank- you name it. Still shows starting tank at 3/4.



And adding to that, my water (after getting it back from the dealership for repairs), is smelling when I first start the sinks/showers. Stinky sulfur smell.



So I ran bleach through the system as advised by the dealership service department. They even gave me a special device to do so. Then they had me leave the grey water tanks open and leave the faucets running to get the bleach full flushed out.



I had to go run an errand and when I came back, my bathroom floor was flooded and it smelled like black water. It took a 3 loads in the honey pot to empty the black water.



I called Keystone to ask if the sink water went into the black water tank and they said no.



Any ideas as to why this happened? Why any of this is happening?