View Full Version : Fresh Water

06-10-2020, 06:50 AM
We are new to the RV world and recently purchased a previously owned but never used 2018 3120 rl. Having an issue with filling fresh water tanks. When filling through what appears to be the proper city water fill valve , water goes directly into the gray water tank. Have to fill through the alternate, rear vent. What's that about? How do I get water to fresh water tank? Suggestions? Similar experiences? Thanks

Montana Man
06-10-2020, 07:46 AM
There should be a lever in the convenience center that directs city water (from the hose) to the coach or fresh water tank.

You may have connected the hose to the black water tank rinse. That is the only 3 routes water can go.

Camp CA
06-10-2020, 08:12 AM
Ditto Montana Man!!............please upload a photo of your system so we can be sure.

06-14-2020, 06:10 PM
Took another look at the RV today. Here is a photo of the convenience center. We connected the city water to the center port and water ended up in the gray tank.....According to the you tube video, the top port is for antifreeze, bottom for black and center for fresh water.

Thanks for your advice.

Montana Man
06-14-2020, 07:11 PM
I can see if the plumbing was done improperly how water could go into the black tank, not grey. When hooked to the lower connection, where does the water go?

Carl n Susan
06-14-2020, 07:31 PM
The grey tanks do not have any fresh water input lines. The only input is from the various drains (sink, shower, etc.). At least that is the way they are built. I think it is time to remove the panel around the convenience center, and maybe the back wall of the passthru compartment and see where the various lines got to. As a previous;ly owned coach there could have been modifications made to the "standard" plumbing.