I have a 67 gallon potable water tank in my 2005 Nash 26X pull along.

I'm just getting used to everything. We went camping this weekend. We slowed down using water when the lights showed two red LED's. Got home and drained the tank into one gallon jugs. I had 40 gallons left. Well I guess I learned something.... when it shows almost empty it's more than half full.

 

Be aware that the slightest tilt off level will make a difference in the reading since the tank is usually very long and wide, but verey shallow.

 

The water level sensors are known to be very inaccurate. Do a search on RV.Net for some reading on them.

 

I've not ever seen RV tank sensors that didn't require a learning curve. Interpretation of level versus my impressions of use.

 

Camper also come with "Lie-O-Meter's" just like the Ram's overhead

 

Don't feel bad. Nothing like going to dump because the gauge was full and you tore down camp for maybe 10 gallons of wast. It is all learning and I have found gauges don't work period after the 1st year. It might be something I am doing but never had a reliable one. Now I just go by the every 4 days rule if not at a full hook up site with 6 people camping. I don't know my tank spec for sure but think the black is 70ish fresh is 60 ish and grey and gally are both 20 or 30.

 

There is a system called I believe, Tank Tender and I imagined there are others, if you're handy you could most probably build one but the way it works it has a probe the ghost Coast to the bottom of the tank and a new pump air and read a very low pressure gauge. The nice thing about this system is that one gauge will read any liquid tank not under pressure. I've heard some people say it won't work in the black tank and I've never tried but it does work another tax from fuel, water and oil. My two cents, Mike.

 

Just noticed this thread. We had a couple of Nash's including an 05 25ft. Our 06 AF has the same tank and sensors as yours. They suck. With the 05 I could use a mirror to shine a narrow beam flash light down the hole that the filler hose goes through (under the sink on that one). Had my wife fill the tank and was able to see the water level rise. After that I could fairly accuratly tell what my level was by looking. I havent tried it with my 06 but I will need to pull some drawers out to see it. Wish there was an easier way to see the tank. Tried using a dip stick through the filler hose.
If you come up with a better idea please post it.

 

If you cut the potable water tank drain line outside the frame rail before the drain valve then Tee in a piece of clear plastic tube run this up through the floor into the tank vent line with another tee. This will clearly indicate exactly how much water is in the tank by just kneeling down and looking at the plastic pipe. You could even mark the tube with a little work.

 

Good idea.