tank level indicators

[popbreed]

Can someone explain the operation of the tank level lights on the panel. Is the lowest level "switch" on the tank hooked to chassis ground and the remaining "switches" will complete the ground circuit when the tank "contents" reaches their level to the lowest "switch"? I have the 1/3 light on the black tank on when the tank is empty. Understanding the circuit would enable me to do a bettered job trouble shooting. Thanks for the help.

[windrider]

You could just have some paper hanging on the sensor, giving you the false reading. I can dump at home, so I fill the tanks till 2/3 full, then wait 2 days or so, and drain. Usually clears the problem. You might get one of the tanks cleaning wands and have a go at it that way.

[cfsoistman]

You have it right. There could be a little TP connecting the 1/3 probe to the the bottom probe lighting the 1/3 light. A build up of debris can do the same as well. Those probes are not real accurate. The grey tank indicators are a bit more reliable due to less debris in the tank but over time if they get a build up they'll read wrong as well. The best I've seen are the Horst Miracle Probes. Much more accurate than the stock probes.

Horst Miracle Probes for Wastewater Tanks in Recreational Vehicles RVs

[flyrotor]

Ditto to the previous responses, also, remember the best way to read the lights, empty is when you get lucky enough that nothing is hung up in there, 1/3 is "not empty" 2/3 means it's time to dump if you can, Full... it might not flush any more.

[herk7769]

The 1/3 light is "Not Empty"

As you can see from the photos, the "ground" for the lights is at the same tank level as the 1/3 light. ANY water, sludge, or slime remaining in the tank will complete the circuit and turn on the "not empty" light.

The 2/3 light is 1/2 tank

The "full" light is about 7/8 full.

Will post links for you.
Watch this video:
http://www.miracleprobes.com/buy.php

Your wiring diagram and trouble shooting guide are also attached.

Horst Miracle Probe 5th Wheel Install #1

Is how I repaired mine.

[herk7769]

Another photo that shows the relationship of the probes.

DO read my install post for why the stock probes suck.

[popbreed]

Thanks everybody for your help. Herk, the links were great and your explanation super. This wonted I am going to switch to the Horst probes in both the black and gray tanks. Fortunately, (or maybe unfortunately) I do not have to deal with the plastic bottom cover. I have contemplated adding an alum. frame work and insulation to enclose the 2 tanks. As in your case, the bottom two are nearly at the same level. My probes are a different design and have a screw terminal in the center. I may just leave those probes in place and add new holes for the Horst probes and move the second probe up the tank an inch or more. However, can you clear this point. I assume the bottom probe is the ground connection to the panel. If so, how does the empty LED light Separate ground in the control panel? The placement is inaccurate because both tanks have a low sump on the empty end and yet the probe placement for the top 3 probes in nearly equally spaced. Thanks again for the help.

[herk7769]

Originally Posted by popbreed

I assume the bottom probe is the ground connection to the panel. If so, how does the empty LED light Separate ground in the control panel? The placement is inaccurate because both tanks have a low sump on the empty end and yet the probe placement for the top 3 probes in nearly equally spaced. Thanks again for the help.

Ok, there is a single probe left of the dump valve (the "ground") and three probes to the right of the dump valve (the 3 light "hots").

When the water level "shorts" the two lowest probes, the 1/3 light comes on. As the water level rises it adds the resistance from the next probe in line and turns the 2/3 light on. when it reaches the top probe all 3 lights will be lit.

oh, and the "empty" led is the "power on" indicator. It lights as long as power is available to the display.

[Bill_C]

Has anyone tried the SeeLevel tank level sensors? There are no probes. The sensor sticks onto the side of the tank and uses the original wires to the panel. It gives a read out in percentage, not thirds. At least this is what I read about them.

[herk7769]

Originally Posted by Bill_C

Has anyone tried the SeeLevel tank level sensors? There are no probes. The sensor sticks onto the side of the tank and uses the original wires to the panel. It gives a read out in percentage, not thirds. At least this is what I read about them.

Bill,

I don't recall anyone posting recently. I would love to hear about their results as well.