CLEANING BLACK TANK SENSORS

[LEAH DRAPER]

Has anyone ever tried to clean the black tank sensors using white vinegar??
I have used it for other descaling issues and have thought about it for cleaning the sensors.

If you have done so what results did you have??

[Tom and Pam Brown]

Leah

On the way to or back from a trip I dump a cooler full of ice in the tank.

If seems to work very well.

[Joel Ashley]

I don't know that calcium scale is the big issue in a black tank, though a gallon or two of vinegar might dissolve some other residues.  The ice and water trick I've heard of before, but I'd toss in some detergent to help put greases and oils into suspension.  Sloshing around for awhile on the road home or to a dump should be effective on all but the most solidly adhered dried gunk.  As to your primary question, I've not tried vinegar myself.  Hopefully someone else here has.

Joel

[Joel Weiss]

We had both our black and gray tanks power cleaned by Deborah Pope in Kerrville TX.  Our black wasn't bad, but an incredible amount of calcium-based material came out of  the gray tank.  I highly recommend having this done, especially on older MH's like ours.

[David T. Richelderfer]

How does one get access to the inside of the tanks with a power washer?  Hmmmmmmmm...

Anyways, I've learned to put some vegetable oil into the tanks after emptying to lubricate the sticky valve slides... not after every emptying, but regularly... like every couple months.  I have electric valves so if the motor doesn't overcome the stickiness, then I'm stuck... can't move.  And it happened once in Rexburg.  After 25 tries the motor got the valve closed... finally... and it was the black tank valve that was sticking partially open.

[Gerald Farris]

Leah,
Vinegar, a cooler full of ice, or a pressure washer may work on the older model coaches, but on coaches with Aladdin tank monitors, the sensor is a pressure sensor and not a conductivity sensor. Therefore, the tank sensor rarely needs cleaning, and many cleaning methods like a pressure washer will do irreparable damage to the diaphragm on the sensor.    

Gerald  

[LEAH DRAPER]

Gerald
I presume when you say pressure sensors in the tanks that when the sensor detects pressure from waste at a particular level in the tank that it then activates the sensor with a resulting light display on readout display.  The issue I am having is that I can throughly drain and flush the black tank (several times) and the display reading will always show 1/3 full.  
Then after limited use it goes to 2/3 full and stays there until it almost full.  

My next step was going to be using a water wand on a garden hose to attempt to clean the tank.  My water pressure here is only about 45-50 as I am on a well supplied water system.  

What kind of pressure ( i.e., what psi) are you saying could damage these diaphragms on these sensors??

Leah

[Gerald Farris]

Leah,
The method that you plan to use to clean your black tank should not harm the sensor, but it probably will not correct your problem. However, it should not hurt the situation, so why not try. I said that a pressure washer would damage the sensor because all pressure washers have a pressure in excess of 1,000 PSI, and the sensor can not stand that kind of pressure if it hits it.

If cleaning the tank does not help, and it probably will not, I would try recalibrating the sensor as per your Aladdin manual. If recalibration does not correct the problem, replace the sensor. Also, if sensor replacement is necessary, be sure to install the sensor in a 90 degree elbow with the sensor facing down. This seems to make the sensor work better and last longer.

Gerald

[Joel Weiss]

I just had my gray and black tanks cleaned by http://rvholdingtankservices.com/ in Kerrville TX.  They used a pressure washer with special nozzles and very thin tubing that they could "coax" into going into the tanks through the outlet.  The amount of calcium-based "stuff" that came out of my gray tank was enough to make me a believer that investing in this cleaning was worthwhile.  We had had some issues with the gray tank prior to the cleaning, but I had no idea how much was inside it.

The cleaning process does get the tank sensors working again but it's possible they will still show erratic behavior due to electrical issues as my black sensors seem to have.  My gray sensors are perfectly fine, but my black ones still jump up quickly to >50% even though they drop to zero when the tank is drained.  I think it's time to invest in a set of SeaLevel sensors.

[Gerald Farris]

Joel,
The tank sensors in your 2000 Thunder are just brass pin pairs that are installed in the tank wall at different levels. When the pins are covered with liquid or debris the conductivity between the pins at that level in the tank changes. The tank sensor module interprets the change in conductivity as the tank being full to that level. That is why tank cleaning helps the accuracy of your tank sensors. However, tank cleaning usually does not correct sensor errors on the Aladdin pressure sensors that were used in the Monaco built coaches.

Gerald  

[Jerry Emert]

Joel,
The tank sensors in your 2000 Thunder are just brass pin pairs that are installed in the tank wall at different levels. When the pins are covered with liquid or debris the conductivity between the pins at that level in the tank changes. The tank sensor module interprets the change in conductivity as the tank being full to that level. That is why tank cleaning helps the accuracy of your tank sensors. However, tank cleaning usually does not correct sensor errors on the Aladdin pressure sensors that were used in the Monaco built coaches.

Gerald  

Gerald, I just bought a 2003 Patriot Thunder.  It has Aladdin controls all over the place that I haven't figured out yet.  Since it has Aladdin does it have the sensors you spoke of?  And since it's an older coach is how should I clean the tanks.  I've been studying every forum I know of and have seen a bunch of different ways people talk about.  What do you think?

[Steve Huber Co-Admin]

Was talking to BCS today on a related matter and asked them about cleaning tank probes. They suggested a mixture of TSP and warm water. Fill tanks about 1/2 full and drive to slosh mixture in tank. Will report if successful. Tried ice this weekend but no joy.
Steve

[Gerald Farris]

Jerry,
Your 2003 coach has a factory installed flushing system in the black tank that will adequately clean the tank if it is used when the tank is dumped. The gray tank can be cleaned in several ways if it is necessary. You can install the same flushing system in it that the black tank has, but this is rarely necessary. The common way to clean the gray tank is to fill it half full of water, add detergent, and drive the coach for at least several hours. The detergent can be TSP or several other good grease cutters. I usually just pour half a bottle of laundry detergent from the dollar store in the gray tank as the detergent. Just remember, we are talking about sewer tanks, and they do not need to be keep clean at all times.

Gerald

[Joel Weiss]

All I can say is that the stuff that came out of my gray tank wasn't going to be easily affected by TSP or anything similar.  Admittedly my coach is 14 years old, but the buildup was substantial and some of the lumps that came out were nearly the size of golf balls. I'm now a believer in power tank cleaning.

[Richard And Babs Ames]

The 1997 Owners manual says to use a certain chemical which the local store said to use powdered dishwasher detergent as it is mainly that chemical as it is low foam and a good grease cutter Put in twenty gallons of water and  the detergent in the gray and black tanks and drive. We also have a flush on the gray and black tanks.