Tank level indicators

[mcoley]

Just used our '07 Antiqua for the 2nd time since we bought it last Oct. Folks on this site have been great at helping me resolve issues. Now I want to know what may be common problems with LED type tank level indicators. I have three: grey, black and fresh. So far I have only used the grey and black. It seems like the black may be working since I can believe that having two LEDs lighted seemed proportional to how much waist I dumped. Note that I use a Flush King to back flush the tank. The grey water tank was nearly full but displayed only the first LED as it does when empty. Can these indicators ever be relied upon? If so, what are common problems that I can look for?

[llowllms]

Chuck_S wrote:
Horst probes in mine the past 6 or 7 seasons. They occasionally show a fuller black tank than is the actual level but they rinse well.

The diagram above is how they're wired. I just replaced the probes one at at time so there was no doubt what wire went to what probe. I needed a thin wrench to get the nuts off. Just ground down a cheap open end wrench to squeeze in.

-- Chuck

Chuck has the solution. I installed the babies five years ago and the have done an excellent job. In fact, I'm putting in a set for a camping buddy of mine this May. By the way, they are not that expensive either.

[Chuck_S]

Horst probes in mine the past 6 or 7 seasons. They occasionally show a fuller black tank than is the actual level but they rinse well.

The diagram above is how they're wired. I just replaced the probes one at at time so there was no doubt what wire went to what probe. I needed a thin wrench to get the nuts off. Just ground down a cheap open end wrench to squeeze in.

-- Chuck

[Jerry9n]

I put in the Horst probes and they have performed perfectly. But, when I did that, I found out the company that built the trailer (now defunct) did a rotten job of placing the probes. I put up an earlier post with a wiring diagram that may be helpful.

Clicky

[Old-Biscuit]

Those 'sensors' are just a metal probe stuck thru the side of the tanks.
4 probes......
1 ground (down low)
1 for 1/3 level (down low same level as ground probe)
1 for 2/3 level
1 for full

They work off conductivity.
When 'wet' a circuit is made between the level probe and ground probe

ANYTHING on them (Stuff, toilet paper, scum etc.) will cause them to register.

You can buy probe cleaners, you can back flush until blue in face, you can use the GEO Method......you can end up pulling your hair out.

K.I.S.S.
When toilet 'burps'........time to dump black tank
When a sink or the shower starts to drain slower then usual...time to dump grey.

[2oldman]

dirty sensor 1
dirty sensor 2
dirty sensor 3

Clean sensors 2010
False black water reading

[glsimms]

I installed the Horst probes during this off-season.

Can't wait to see how accurate thay are!!

[Campfire_Time]

These are like the idiot lights in your vehicle. They are just a guide. Don't rely on them, but don't ignore them.

[Padlin]

I've never had problems with the grey or fresh, just the black. The black can read 2/3 or full at any time and any level, I've gotten used to how long we can go before worrying about how full it is. As that point I do like Dan mentions and use a flashlight.
Your grey issue sounds like a bad sensor or wiring. Although I've tried, I've never been able to figure out how they work so I'm no help fixing it.

[bikendan]

mcoley wrote:
Can these indicators ever be relied upon?

NO!!

a quick search on any RV forum, about the OEM sensors, would give you months of reading about how nearly useless they are.
many install aftermarket ones, like Horst Probes, for better accuracy.

many of us simply shine a light down the toilet, for better info.:W

[Oasisbob]

I use flush King as well. Great invention. Still my guages lie like politicians. After nine years of camping with this HTT I still wonder if my geay and black sensors are crossed.