Black Tank Sensor reading full when not - '21 2400BH

[GrandDeal3]

Just picked up 2021 GD Imagine 2400BH this past weekend 3/26 from private seller. Only had 2 trips on it and I put more miles on it taking it home than he had in the combined trips (he's upgrading to 5th wheel). I stayed at campground overnight since it was long drive and the Black Tank always read 1/3 full no matter what. I emptied at site, ran water down toilet etc. but still always read at least 1/3 full.

Called prior owner and he said it was a 'known issue' with GD and just to keep eye on it. I am not terribly worried as we wont be doing any LONG dry camping but I was wondering if anyone knew if this was just a sensor malfunction or if I need to reach out to GD on this.

Im handy so I can fix if its just a part but I want to hear the chatter on this.

[Country Campers]

A well known issue throughout the RV world. Keeping the tanks clean and well flushed is key , as well as prefilling the black tank with about 10 or 15 gallons of water to help break down the masses. Anything caught on the sensors would give a bad reading. I would not be too concerned about it , enjoy the camper and have fun.

Brian

[GrandDeal3]

Thanks Country Campers . I'll keep'em clean and just camp on. First real trip with the fam Ill put 10gal in it to make sure it rinses out real well.

[ncitro]

Thanks Country Campers . I'll keep'em clean and just camp on. First real trip with the fam Ill put 10gal in it to make sure it rinses out real well.

Brian is exactly right. The sensors are little metal electrodes that are mounted to the sidewall of the tank at different heights. Without getting too gross, anything other than pure liquid is bound to stick to be sensor’s and cause it to think the tank is full to that level. You should expect the same issues (although to a lesser extent) with the grey tanks.

Practically it would be difficult to fill the black tank in less than a few weeks. I’ve had four adults in my rig and intentionally gone as long as I could without dumping it. I got to two weeks before I gave up and dumped it.

You can kind of tell it’s getting full based on the sound when you flush. If you’re really worried about it (nice to know when flushing the tank) I have the seelevel system where the sensors mount on the outside of the tank and it reads in 1% increments. Nice to have a second display in the wet bay as well.

[GrandDeal3]

Brian is exactly right. The sensors are little metal electrodes that are mounted to the sidewall of the tank at different heights. Without getting too gross, anything other than pure liquid is bound to stick to be sensor’s and cause it to think the tank is full to that level. You should expect the same issues (although to a lesser extent) with the grey tanks.

Practically it would be difficult to fill the black tank in less than a few weeks. I’ve had four adults in my rig and intentionally gone as long as I could without dumping it. I got to two weeks before I gave up and dumped it.

You can kind of tell it’s getting full based on the sound when you flush. If you’re really worried about it (nice to know when flushing the tank) I have the seelevel system where the sensors mount on the outside of the tank and it reads in 1% increments. Nice to have a second display in the wet bay as well.

Thanks ncitro . I agree that it would take alot to fill the Black up. We have 5 but that is 2 adults, 5y/o, 3y/o, and 5mo in diaps....not too worried haha. Ill have to check out SeeLevel. Let me know if you have any RV insurance questions (I replied to your other post as well).

[Yoda]

Just picked up 2021 GD Imagine 2400BH this past weekend 3/26 from private seller. Only had 2 trips on it and I put more miles on it taking it home than he had in the combined trips (he's upgrading to 5th wheel). I stayed at campground overnight since it was long drive and the Black Tank always read 1/3 full no matter what. I emptied at site, ran water down toilet etc. but still always read at least 1/3 full.

Called prior owner and he said it was a 'known issue' with GD and just to keep eye on it. I am not terribly worried as we wont be doing any LONG dry camping but I was wondering if anyone knew if this was just a sensor malfunction or if I need to reach out to GD on this.

Im handy so I can fix if its just a part but I want to hear the chatter on this.

Before your next trip put 1 cup Dawn dish soap in the tank with 15 gallons of water and drive. Find the twistiest route you can. The Dawn will help break down any collected STUFF and clean the tank. In your case I would also add a TIED laundry pod to. It should help break down any piles.

When I get ready for a trip I add the Dawn and 5 gallons of water to start. No need for any expensive chemicals.

Keith

[Salty_NewEnglander]

Brian is exactly right. The sensors are little metal electrodes that are mounted to the sidewall of the tank at different heights. Without getting too gross, anything other than pure liquid is bound to stick to be sensor’s and cause it to think the tank is full to that level. You should expect the same issues (although to a lesser extent) with the grey tanks.

Practically it would be difficult to fill the black tank in less than a few weeks. I’ve had four adults in my rig and intentionally gone as long as I could without dumping it. I got to two weeks before I gave up and dumped it.

You can kind of tell it’s getting full based on the sound when you flush. If you’re really worried about it (nice to know when flushing the tank) I have the seelevel system where the sensors mount on the outside of the tank and it reads in 1% increments. Nice to have a second display in the wet bay as well.

Thank you for the note on the SeeLevel system. We purchased our 2800 in August and have been "learning" to gauge where the black tank really is.

[J & J Bumblebee]

This happened on our Winnebago Micro Minnie. The black water tank read 2/3 full just after I dumped it. Talked to the dealer and they said something was stuck on the sensor, don't bring it in just fill it and drive around. It worked.

I'll have to try the Dawn thing, I bought some chemical for loosening the crud, when that's used up we'll do the Dawn thing..


Thanks for the information!

John

[PSI Scribe]

I'm having the opposite problem. My Black tank sensor never reads "full". 1/3 and 2/3, fine and dandy. But not full. I'm assuming it's likely a wiring problem between the sensor and the display panel. Fresh water and Grey tanks are OK. Anyone out there with a similar problem?

[howson]

I'm assuming it's likely a wiring problem between the sensor and the display panel.

...or an issue with the top right sensor/red wire on the tank. The diagram below was clipped from a Lippert (LCI) presentation and shows how a typical tank is configured. (Doesn't matter if it's a black, gray, or fresh water tank--the OEM provided setups work the same.)

[Scott'n'Wendy]

I don't have one but I know a couple couples with the Seelevel system. No complaints.
It would seem to me it would be easier for GD to install a Seelevel type monitoring system because you just attach to the outside of the tank with 3M tape instead of drilling and installing little electrodes. I would think it would be quite a time saver during manufacturing. I have to think cost difference would be a wash.
Even marketing could boast that their RV's give accurate tank readings...unlike everybody elses.

[Dennis66]

I had problem with our class A years back and what I did before next trip, I put 2 bags of ice in toilet and let that help scrub off the bottom of tank of any buildup while driving to destination. Seemed to work in cleaning pyramids we had bought that used. With our new rig I do add a few gallons of water before each trip need to try the Dawn treatment.

[cvretis]

All of my three tanks have bad readings. We have only been out two times on a new 2021 unit. Any suggestions?

[Schiefswret]

Before your next trip put 1 cup Dawn dish soap in the tank with 15 gallons of water and drive. Find the twistiest route you can. The Dawn will help break down any collected STUFF and clean the tank. In your case I would also add a TIED laundry pod to. It should help break down any piles.

When I get ready for a trip I add the Dawn and 5 gallons of water to start. No need for any expensive chemicals.

Keith

or 20 Mule Team Borax

[Cate&Rob]

All of my three tanks have bad readings. We have only been out two times on a new 2021 unit. Any suggestions?

The only way to be sure that you won’t get random false readings is to not push the button on the panel . After trying all sorts of cleaning schemes, I just gave up. We manage tank use by conserving water when necessary but always keep a minimum of 10 gallons of water in the black tank (measured with a flow meter on the flush line). The sink drains and the toilet flush will sound different when the tanks get close to full . . . this is all that you really need to know.

Rob