Bounder: Holding tanks sensors

[hhcruisers]

We recently purchased a 2010 Bounder 33U on a Workhorse Chassis. We have had issues with the holding tank sensors since day 1. The black water tank sensor only registers E immediately after it is emptied, then goes to the 1/3 level. And our gray water tank was all over the place for a while. We have had the coach in twice to get this problem fixed and so far the dealer and it seems Fleetwood can't come to an agreement on what needs to be done. Now the gray water tank registers at Full all the time. Has anyone out there had any similar issues? Any ideas on fixes? We would appreciate the help.

[The General]

hhcruisers,

Congrats on your new Bounder.
I would check that the ground wiring has been properly attached and would get the diagram from Fleetwood 800-322-8216. You will need your FIN# to get this by email. Use the flush option to clean the black water tank and clean all tanks with liquid bleach.
It's a place to start,


Steve

[Mr_D]

You may want to investigate getting the external sensor units, they don't usually give false readings once they are set correctly. We have them in our DSDP and after 9 years they still function with no problems. I did have to adjust the "pots" to get them set, since then I've never touched them again.

[njs42]

MY nine year old sensors are internal and they work fine but require a rather judicious regimine of flushing and care to prevent gumming up and reading "on or full" all the time. It is "work" but pays off knowing that they do preform correctly.

Exterior sensors that work properly sound as though they minimize any such efforts so would be a good investment. If mine did not work I would go that route, I believe.

I also find my interior sensors subject to moisture. For instance sometimes they show full---but if I hold the switch a few seconds longer they "dry out" and register correctly. No doubt they can lead to some exasperation----cleaning and keeping track can preserve them in an operable state for many years.

So, check the ground (good idea) clean, then look for other problems. Good luck.

[hhcruisers]

Thanks all for the advice. We will work our way through this. Eventually, we will get it resolved.

[wa8yxm]

First let me describe the sensor itself.. A nail, nothing more, (or screw) pushed through the side of the tank into the slurry inside. That's all it is, a simple metal pin, nothing about it can possibly go wrong, Absolutly NOTHING. (Well it could corrode off I guess) but read on.

Sludge can build up on the side walls of the tank, keeping this pin wet all the time, this results in a false "Fuller than it really is" reading, This is very common, in fact if someone tells me they do not have this problem...... I DO NOT BELIEVE THEM!!!!.
(Exception, something like the See-level system which uses different technology)

Second a bad ground can cause a false reding as well, and lastly a bad resistor pack or wire can cause no reading at all (Always empty)

How it works

The panel puts a constant current into the wire, or tries to, It then reads the voltage on that wire.. Battery voltage (or rather reference voltage) means the tank is EMNPTY

THe wire goes first to the FULL sensor, then via a resistor to the Near full, then via a 2nd Resistor to the next sensor down to the near empty (on my tanks that is like this:

Panel--------FULL--\/\/\/\--2/3--\/\/\/\/-1/3

And that's all

The panel then tries to read the voltage on the long wire in that diagram

As I said Reference = EMPTY or nearly so
High but lower than Reference = 1/3
Low, but greater than zero = 2/3
Dead short to ground = Full

A ground fault on the panel means the ground is at reference voltage, thus the panel senses full

As the water rises in the tank, being conductive (normally) it "Shorts" each probe to ground..

Tethford tank products with Sensor Cleaner are identical in contants (ingredents) to therir non-sensor cleaner products save for one thing.. Common table salt. Which is a corrosive agent and does nothing to clean the sensor.. IT does, however, improve the conductivity of water.


SO, how DO you clean the sensors? Two ways that I know of that work.

How I do it, normally: I made my own version of the Valterra Masteer Blaster tank rinsing wand. I blast the sensor wall clean.. DOES NOT ALWAYS WORK.

I've also recently added the RV-Twister from Camco as of yet I've not had success with it but see the above.. I'm still testing.

GEO-Method.. Many folks will describe or you can look it up in forum libraries,, Basically you dump add 1/2 cup each Calgon water softener and Dawn Dishwashing liquid (original formula not anti-bacterial) and say 1/3 tank of water. DRIVE and slosh about, dump again,, NOTE at finish of this procedure tank will read full.. ... of soap bubbles.

[pcurt23]

You probably already have external sensors. There is a 2010 Bounder in our camping group and it has external sensors. They also have a tank level reporting problem.

pcurt

[Camping4fun]

We have a 2009 35E with the same problem. I called Fleetwood on it and was told by there tech that one are two gallons would cause it to show 1/3 full. This is the way it was set up to work, that way people don't over fill them. I don't think that's right but what do you do.

[hhcruisers]

That is good to know that we are not alone! Thanks for all helpful info. We will work on it some more this weekend.