Control/monitor panel question

[Naomi]

We have recently purchased a 2008 Raptor and I'm hoping someone can give me the "dummies" version of the control/monitor panel lights. I understand the empty to full series of lights and the fresh water indicator, but what exactly is the holding, gray 1 and gray 2...why are there 2 gray water tanks? I have attached a picture of what my lights currently look like after having opened and let drain the 3 white drains under the trailer, as well as having drained the sewage drain on the back of the trailer.

Any guidance is greatly appreciated!

[MattE303]

"holding" is your Black tank (the toilet). When you have 2 gray tanks, most typically, one of them is the shower and bathroom sink, the other is the "galley" (kitchen) sink.

If you have 4 drain valves, 1 is your black tank, 2 are for the gray tanks, and the last one is probably your fresh water tank.

It's very common for the level indicators to not read "empty" even when the tank is empty, either because they are malfunctioning, or there is "matter" on the tank walls that is causing the false positive.

There are a few different techniques for flushing/cleaning the tanks which will sometimes get the level sensors reading correctly. Does you trailer have a "black tank flush" hose connection in the convenience center (where you fill the fresh water and such)?

[Naomi]

Thanks for the prompt response! I will look tomorrow for the tank flush hose connection and let you know!