Black Tank is Empty... BUT Red Light is Still On!
When your RV black tank is full, the red light on your Dometic 8700 Macerator toilet control goes on. This signals you are no longer allowed to flush as a safety feature to prevent you and your travel guests from over filling your black tank. This electro-mechanical float device is a great idea until it decides to get “stuck” in the up and “activated” position.
When this happens, its “no more flushes for you!” The sensor needs to drop down OFF the sensor PICKUP SECTION of the switch. Even with our tanks newly emptied, the red light remained on no matter what I did.
This created two problems. Obviously we no longer could use the RV facilities. And although I could FILL fresh water into the black tank via the rinsing port, I was NOT ABLE TO INTRODUCE (via flushing) any cleaning agents into the tank such as Cascade Dish Washing Soap and/or Dawn Dish Washing Soap.
If I could have introduced those cleaning agents, we would have expected this would have removed and sloshed away any “debris” stuck to the float sensor device. This is something we regularly do as a preventive measure.
We thought we could reset the Dometic Control Sensor Light by just flushing the black tank of any “debris” stuck onto the sensors. But this alone simply did not work. As you can see by how the motorhome sprayer is designed, it’s not really that aggressive of a power washer. Once you are in trouble like we were, you need the sloshing action of a nice long drive with “bubble bath water” inside your tank. That would have done it!
What Did We Do Wrong That Created This Issue?
Over the last 5 years of full-time RV Living, we have had this light go on a handful of times. But it has always happened at a campground when we were STATIONARY. It ALWAYS would reset after a good flush, within a few minutes. What was different this time was we had just finished DRY CAMPING the 2022 Florida RV SuperShow for 6 days prior. This light came on during the drive to our next campground which had a full hookup. Apparently enough “soil” splashed on and around the sensor for 200 miles that we sealed our own fate. We drive with a partially full black tank a lot when we go from sites that are dry camping only. I believe the difference this time was we must have been only a few flushes away from being totally FULL.
So what was our next step in the trouble shooting process?
You guessed it! After some deep diving and googling it was:
IRV2 - Cut Some Wires!
With some guidance from irv2 forum, we were able to figure out a solution and then put in a switch on the wires we cut in case we have this problem again. Just remember to turn the switch on to prevent any future roof top “over flows”!
You can see we eventually had to remove our pegboard shelving to get to the tanks. If you are interested in seeing more about Mark’s shelving design or the SeeLevel tank sensor gauges, see this video, EP 22.
IRV2.COM Website Saved Us Again!
This link is within the Newmar Owners Forum area in the irv2.com article universe. If your RV is a different brand, you of course need to get into that section within irv2.com You can VIEW and SEARCH within irv2.com for FREE. To actually ASK a question on the site, you need to become a member.
The website resource iRV2 is completely free for anyone with an email address. Just visit iRV2.com or click this registration link to join! Once you are a member, resist the temptation to ask ALL questions except the most complex or urgent. This data collection is so powerful and complete, almost everything has been asked and discussed already,………20 TIMES OVER! Do your homework first and use the “magnifying glass” to search your topic of concern.
This link has individual “comment numbers” in the upper right hand corners of the entire discussion thread. Read ALL the comments in this thread from beginning to the current end before deciding what to do. Pay attention to the brand, year, model name and model numbers folks are talking about when discussing their solution to the issue. The ones that are particularly helpful are #6 (by Dutch Star Don), #47 and #84 (ANYTHING by VP Chianese) and #60 (by RMD3819).
Learning to trust and use irv2.com will be the best thing you will ever do as an RV owner. The fact that this resource is free is beyond comprehension to me. Thank you Social Knowledge, LLC for sponsoring this crucial resource for all RVers now and hopefully in the future. Folks should familiarize themselves with the currently 30 RVing websites, forums and groups they sponsor!
Check Out Our Video EP 217 to See How We Solved the Problem(s)!
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3 Responses
Thanks for the great video. Saved my butt.
Theo where there is a will,… there is a way! Thanks for the info for the DIY crowd and folks looking for a true camping adventure!
Plenty of free plans on-line to let you make a DIY composting toilet, no moving parts, no electrical need, all for around $20 or less, unless you wanted to get fancy and then it would be a bit more. I got my seat, fits on top of a five gallon bucket, cost about $11. A five gallon plastic bucket can range anywhere from free to maybe $10, but more likely around $5. I already know how to make one, but bought a copy of Humanure anyway, it has plans for making one, and shows a variety of types, but bought it because I had a copy years back, and it is a really interesting read (in my opinion anyway), got it on-line, for just over$5, think used, but looks new, just shop around some. I have seen them built into chairs, just raise the chair seat, or foot stools, just raise the top – handy because you can move them around if need be, to use the space they are in.