Waste pumps

[MONTIE]

I have bought a 2008 Monaco Knight 40 DFW and it has Santi-Co and Aelectric comodes. They both seem to work great, but for some reason I cannot empty the black-water tank completely. The pump runs until it is out of liquid, but the sensor displays 1/3 full. Any suggestions?

[wolfe10]

Most likely issue is a tank gauge that is not reading accurately. This is a VERY common occurrence.

To minimize this (not eliminate it) you can do several things:

1. Only drain the tank when it is more than 1/2 full (unless getting ready to hit the road). If you drain with less than 1/2 tank, add water with flush system or through one of the heads.

2. After draining, add at least 5 gallons of water, so waste can not fall into a dry tank.

To clean tank sensors:

1. After draining and rinsing, add 15 gallons of water. Right before you are ready to hit the road, flush 20 pounds of ice down the toilet (assuming it is not a macerator-based toilet). The idea is to get the ice as is into the tank. The ice will slosh around while driving and clean the sensors and tank.

2. You can also add a few ounces of Dawn dishwashing detergent and drive with that in the tank.

Brett Wolfe

[MONTIE]

I think that I did not put enough water to the tank and I have a build up in the tank. The comodes are macerators, will the Dawn work if that is the problem. It has a rinse, evry time I have rinsed the tank but it still holds about 1/3 reading.

Thanks

[wolfe10]

Yes, a detergent will help. As will driving with 15 or so gallons of clean water in the tank-- not as much "cleaning action" as ice, but with macerator-based toilets, you have no practical way to get ice in the tank.

Another option, particularly if you suspect a buildup of solids is to use Rid-X or other biological product for septic tanks along with water in the tank to break down the solids. These work best when you are storing the unit, as they work over time.

But expecting tank gauges with internal sensors to always be accurate may be setting too high an expectation.

Brett Wolfe

[tbutler]

In addition to the above, I always try to empty the black water tank after driving rather than before driving. That means when you are traveling from one RV Park to another, I dump the tank right after arriving at the second RV Park. That way, everything in the tank should be well stirred. If you dump then, the solids won't have a chance to settle to the bottom. If you are going home, it means dumping the tank at home or at a RV Dump somewhere on the way home. The longer and rougher the drive, the better for dumping tanks afterward!

One method we use when dumping that I think will work for the macerator toilets also is to fill the bowl with water and then flush as the Sani-Con pump is running out of fluid. I use several 2 gallon buckets and fill them with a hose outdoors. This process puts a large amount of water down into the nearly empty tank directly below the toilet drop zone which is where solids tend to accumulate. I do this after running the tank rinse for the entire dumping process and it runs clear. When the toilet is flushed, significant solids come out with each flush up to the third time. By then, everything is running clear. This indicates to me that the standard tank rinse system doesn't really move nearly all the solids out of the tank.

Another thing you might try if this is possible. If you have an option to unhook the Sani-Con, do so and put a regular 3" hose on to dump the black water. We have a macerator and it doesn't empty the tank as rapidly as a 3" hose. That means that with the macerator, the water isn't flowing out of the tank with anywhere near the speed and energy as with the 3" hose. The faster the water flows, the more solids it will move out of the tank. I try to use the 3" hose occasionally while traveling and all the time when parked for the winter. I save the macerator for those times when I want a quick convenient dump or when using a sewer connection designed by someone who didn't understand the finer points of waste plumbing and gravity!

My black water tank gauge hasn't worked accurately for years. I had it recalibrated at the factory but that only lasted for six months or so and soon the readings were off. In the meantime, I figured out by experience how long Louise and I could go before the black water tank would be at a critical level. I also learned how to tell that the black water tank was nearing full! So now I know our tank will hold almost two weeks of flushes. I make a note on my computer calendar (BWT Dump) and plan to dump somewhere near the end of the two weeks from there. I no longer even look at the black water tank indicator, I don't need it.

[MONTIE]

Thanks giys, I appreciate the info. The only problem I may have if I cannot get this resolved is the commodes may not flush if I am in position that the commoded give a full signal. IN the book it mentions this could happen. I think I will try the Rid-X, soes it need to when the coach is a rest not being used

[wa8yxm]

Tank sensors are nothing more than a screw or nail, That's all, that extends into the tank, If it's "Moist" then it shows that the tank is "That full" (there are usually 4 or 5 of them, the number of lights on your panel plus 1 (Ground))

To get the thing to read right you really have to blast the sensor wall.. OR, change sensors. (more on that in a second) To properly clean the sensor wall, on the black tank only.. You could use a product from Valterra,, It is called the MASTER BLASTER,, This is a tank flush wand with a miniture "Fire nozzle" on the end, you point it toward the sensor wall and move it up and down, twist righ and left and it blasts any slime off the wall and lets the sensors work properly.. Works fairly well... Though Mine is home made, not a Valterra.. I've only seen one store that sold it.

I have also had luck with the "Geo" Method.. Dump, add 1/2 cup Calgon water softener (Powder or liquid) 1/2 cup REGULAR (not anti-bacterial) Dawn dishwashing liquick, about 5-8 gallons of water (I added six) and drive.. 50-70 miles, then dump again.

However I mentioned above two other sensors

one is the See Level System (Google: See Level RV) This is an external sensor, it sticks to the outside of the tank, and uses some electronic magicery (Capacatince) to measure the level in the tank. This is a full system, it is 100% different from your current sensors.

The other is HORST sensors.. Now, I have seen the See-Level system with my own eyes, Never seen a horst sensor save on the net.. But folks who use 'em swear by, not at, them (So far) I plan on upgrading.. Some day.

http://www.horstmiracleprobes.com/buy.php

As I said,, I've not tried them.... yet.

[bwwaddell@yahoo.com]

When adding Dawn, be sure to put the water in first, then add Dawn. Otherwise you will have bubbles sprouting out your vent.

[cebuffett]

I have the same toilet / SaniCon setup. I have used the method recommended in the SaniCon manual quite sucessfully. It uses the contents of the gray tank to rinse the black tank. By empting the black tank and then rinsing it this way two or three times, it seems to do a very good job of removing the solids.