Two RV Holding Tank Rules
Rule #1: Think before you panic!
Once he had possession of the 5th wheel and was living in it, he discovered his black tank dump valve was stuck open. He thought this was better than having it stuck shut, but that is not true either.
Any experienced rv'er with a motor home, travel trailer, or 5th wheel knows the black tank should only be used with the dump valve CLOSED so that liquids and solids are together.
If there are no liquids in the black RV holding tank this obviously leaves only solids which eventually will lead to black tank flush problems. I was there to replace his black tank dump valve and once I was into the job I discovered I didn't have the correct dump valve to complete the job therefore, I left everything as I had found it...valve open as he had been using it. By mid afternoon he called the office with what he thought was a problem, of course caused by no one else than "yours truly".
I called him for the specifics of his problem and this is what he told me. "My toilets plugged so you must have done something to cause this." I responded that I left the black tank valve "open" just as I had found it. I then calmly asked him this question : Are you telling me you filled your black RV holding tank since I left you? (He was assuming his tank must be full). After being presented with this question and pondering over it, he knew this likely was not the case. All he knew was that his toilet was plugged. (Yuk!)
Toilets with angled pipe to the black tank require lots of water to properly flush. I have also learned this the hard way with our Holiday Rambler 5th wheel. Angled pipes from the toilet to the holding tank plug easily but the good news is its easy to diagnose. Here's some pointers :
Normally this procedure will be successful (if the tank is not full). If it is not successful and the tank is not full most likely this problem has been developing and growing worse with time in an RV that is not used on a regular basis, and guess what? This blockage has had time to sit and dry out...only exacerbating the problem. Your option now is to let it sit and add an environmentally safe substance that will hopefully break down the blockage. If time is of the essence someone (like me) is going to have to try to ream the blockage out or the last resort, tear things apart.
Ray Oberreuter is a RV technician has a web site on information regarding the technical aspect of rving. He has articles to help you on batteries, electrical, holding tanks, purchasing used rv's, motor home chassis and much more. http://www.rv-motorhome-answers.com
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