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superrayzor's avatar
superrayzor
Explorer
Jun 27, 2016

Gray/Black sensor problems

Been having issues with my gray/black sensors recently. Even after dumping it reports 1/3 full on black and 2/3 on gray.

First I verified that it was draining properly - after emptying I put a bowl of dyed water down the gray, and then I drained it into the bowl and got back the same amount and it was dyed.

After I empty I put Calgon/Blue Dawn in the holding tanks with 4-5 gallons of water. Yesterday I put all hot water in the gray tank with a generous amount of both before heading out on a 4 hour drive to try to let it swish around and clean the tank and sensors.

Is there anything I can do to fix it? The unit is less than 3 months old.

26 Replies

  • Thanks all - can I remove the probes/sensors and clean them off manually? I see there is some red sealant on the outside which I don't have so I am worried about taking them off?
  • Common problem. Fairly difficult to keep the sensors clean as they require constant cleaning.
  • Yea I got used to my black tank sensor being wrong. Everyone once in while ill travel with my black tank half full of water and treatment to get rid of the smell and clean off the sensor. but by the end of the trip the sensor is messed up again

    I do take care of my fresh water tank and sensor though. Where I live we have pretty hard water so the tank/sensors can get build up and jam the inline filter
  • superrayzor wrote:
    Been having issues with my gray/black sensors recently. Even after dumping it reports 1/3 full on black and 2/3 on gray.

    Is there anything I can do to fix it? The unit is less than 3 months old.


    This has nothing to do with the age of the trailer but rather the simplistic sensor probes which protrude into the tank and therefore clog quite easily. Many if not most of us who have been at this for awhile have decided we just don't care but for those that do the solution is to switch to a tank monitoring system using sensors that don't protrude through the tank wall. Walex recently introduced a tank cleaner called Commando that is designed to clear the probes ... I've used it myself and it does seem to clear a lot of additional crud out of the BW tank.
  • superrayzor wrote:
    Been having issues with my gray/black sensors recently. Even after dumping it reports 1/3 full on black and 2/3 on gray.

    First I verified that it was draining properly - after emptying I put a bowl of dyed water down the gray, and then I drained it into the bowl and got back the same amount and it was dyed.

    After I empty I put Calgon/Blue Dawn in the holding tanks with 4-5 gallons of water. Yesterday I put all hot water in the gray tank with a generous amount of both before heading out on a 4 hour drive to try to let it swish around and clean the tank and sensors.

    Is there anything I can do to fix it? The unit is less than 3 months old.


    Did this help??

    Personally, instead of using a dishwashing soap that makes tons of suds, I use a laundry detergent (Oxy-Clean), that seems to do a better job. Each morning, prior to travel, I use the liquid Oxy-Clean and liquid Calgon along with about 5 gals of water and I never experience odors or faulty tank gauge sensors. On non-traveling days, and when dumping the black tank, I will use the soapy water from the gray tank to help flush out everything in the black tank.

    If you haven't headed out yet, let us know after you have completed your initial trip. You may have to do this several times if your tanks are really dirty.

    Be sure to ALWAYS use LOTS of water in daily usage and when draining.

    Good luck

    Ron
  • After reading posts about this for years, I've concluded that almost nobody has working sensors.

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