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2003 Minnie Winnie Fresh Water Holding Tank Problems.

by glen
(dallas texas)

We bought a 2003 Minnie Winnie that sat unused for 3 years. The previous owner left water in the fresh water holding tank. Now the meter reads 2/3 full all the time. Also, we are having trouble draining the water from that same tank. We used the bleach/water sanitizing recommendations for cleaning, but not sure about these other issues.

ANSWER Hi Glen, congratulations on your new RV. Since you have already sanitized your RV's fresh water holding tank, we will not go over that procedure here. But if any of our visitors are interested in learning how to properly sanitize their RV's fresh water holding tank we have a great article in the RV Lifestyle Articles section of our website by RV Expert Mark Polk from RV RV Education 101 called Freshen Up Your RV Water System.

Depending on the length your Minnie Winnie is, you either have a 30 or 40 gallon fresh water holding tank. When you sanitized your fresh water tank, I assume that you ran your RV's water pump until no more water was coming out of the faucets. If you still have water in the tank and you want to get rid of it, you are going to have to locate the drain plug or drain petcock for your RV's fresh water tank. To locate this drain you are going to have to crawl under the RV and locate the freshwater tank and then the petcock or drain plug. These drain plugs or petcocks are usually located near the bottom of the tank. Remove the plug or open the petcock to drain all of the remaining water out of the tank.


Helpful Tip: If your RV's fresh water tank only has a plug, now would be the time to go to the hardware store and buy a petcock or ball valve and install it on the tank. That way it will be a little easier the next time you decide to drain the fresh water tank on your RV.

Now to your fresh water tank gauge (dummy lights) issues. One of the most common complaints by all RVers is that the gauges or dummy lights for their RV's holding tanks are either inaccurate or non-functional. There are several ways that the levels of holding tanks can be measured, it varies by RV manufacturer. In some cases probes are actually drilled into the side of the tank to measure how full the tank is. Other times they use sensors taped or glued
to the outside of the tanks, etc. Regardless of which method is used most RVers will tell you that they do not work most of the time. below is a ranking report of which tanks in the RV experience the most problems.

1. Black Water Tank
2. Grey Water Tank
3. Fresh Water Tank

As you can see the fresh water tank does not normally have as many problems as the grey and black water tanks do. Below is a ranking of the causes of these measurement problems.

1. Dirty sensor or probe.
2. Bad sensor or probe.
3. Bad wiring to sensors or probes.
4. Bad RV Monitor Panel

in all likelihood, your sensor or probes are dirty or corroded. If you live or travel in areas that have hard water you could have mineral deposits on these probes causing them to malfunction. These mineral deposits will also affect your hot water heater.

There are all kinds of chemicals you can buy that will clean the probes and sensors in your black and grey holding tanks, but these products (chemicals) should not be used in the fresh water tank. You do not want to put any of these products in your fresh water tank due to chemical residue, after all this is the water you are going to be drinking, showering with, washing dishes with, etc. Some RVers have used a little baking soda or vinegar in their fresh water tanks and drive around for a while and then flush and drain their tanks in the hopes that it will fix the problem.

If the above method does not work for you, then you are left with three options.

1. Take the RV to an authorized RV mechanic and have them diagnose and repair the problem.

2. Install an after-market holding tank monitoring kit. Some of these kits are even wireless, so you do not have to run any wiring from the tanks to the monitor.

3. Do what a lot of RVers do and just do not fix the problem and live with it. A lot of RVers have learned by experience and instinctually know when they need to dump the tanks and when they need to fill up the fresh water tank.

I hope that this information has helped you. If any of our visitors have any tips or tricks to add they can do so by clicking on the add a comment link near the bottom of this page.

Happy RVing

RVing Al

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