My RV's Holding Tank Gauges are Inaccurate

by Anonymous

How to Fix Your RV's Inaccurate Holding Tank Monitor

How to Fix Your RV's Inaccurate Holding Tank Monitor

Why does it seem every time I empty the holding tanks at a dumping station the monitors always read that liquid is still present?

ANSWER: Hi, this is one of the most common complaints among all RVer regardless of what type of RV they have. The fact is that holding tank gauges in RVs are notorious for being inaccurate.

The most common cause for the gauges not showing the proper level in your holding tanks is due to the probes used to measure the waste level in the holding tank being dirty, which causes them not to work. The first thing you can try is some RV Probe Cleaner and see if that gets the probes working again. Do not use probe cleaner in your fresh water tank.

Some RVers have had good luck by dumping some original Dawn Liquid Dish Detergent in their Black and Grey Water Holding Tanks. The Dawn seems to break up all of gunk on the probes. Again, do not use the Dawn in your Fresh Water Holding Tank.

Thetford Tank Blaster

Many RVers swear by Thetford Tank Blaster (pictured above). Just add the reccommended amount to your RV's Black and Grey Holding tanks and let it sit for at least 24 hours and dump your tanks and all the crud should be eliminated.

Sometimes dumping a couple bags of ice cubes into the holding tank and driving the RV around will help clean the probes.

If the problem readings are coming from your Black Water Holding Tank you can get a flexible tank wand or a Master Blaster Tank Wand and use them through the toilet to help clean out the tank and the probes.

If none of the suggestions above work, there could be other problems causing the gauges not to work, such as a bad sending unit, a bad gauge, etc. In those cases you would have to have a Certified RV Technician diagnose and repair the problem.

Over 1,500,000 successful roadside rescues—Good Sam RV Emergency Road Service

Some RVers just throw up their hands in frustration and just give up on the tank gauges ever giving accurate readings and have become pretty good at just knowing when to dump the tanks.

Hope this helps.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

Happy RVing

RVing Al

Comments for My RV's Holding Tank Gauges are Inaccurate

Average Rating starstarstarstarstar

Click here to add your own comments

by: Anonymous

Original Dawn Dishwaher Liqud

Use 1/4 cup Dawn and 2 gallons of water in the tank with faulty readings. Then drive to your next RV park, hopefully, a couple of hours driving time or longer. Empty the tank upon arrival, the reading should show empty.

Click here to add your own comments

Return to Ask an RV Question.