This was a problem for our 2019 R27-OB as well. We installed the same Fill-Rite flow meter (TT10ANC) as Barry, but I can tell you the manufacturer will say that model is not recommended for saltwater. If fact, the flow meter on Barry's former R27-OB quit working and was replaced with a polycarbonate model that the manufacturer does recommend. Once receiving the proper unit, it is easy to do the inline installation on the raw water supply line forward of the "T" fitting that supplies the raw water washdown pump. Good luck!
I just installed the SCAD monitor for my holding tank, the existing Tecma sensors always report green on my tank.
I just calibrated the tank last night during a pump out and now it's successfully reports full and empty, and while pumping another full tank of water out, it goes down smoothly on the 10 LEDs every few seconds. Perfect
It only took 3 hours to install, most of the time spend was pushing the wire from the tank to the toilet location, I ended up needed to remove the tank holds and slide the tank forward to re-plumb the snake, if I did this from the start it would have been even faster. I tapped into the 12V from the cigarette socket in the berth that is right behind (which has been replaced with a couple of USB only plugs)
