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Author Topic: dumping system  (Read 398 times)


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dumping system
« on: July 23, 2017, 06:06:11 PM »
Hello to all,
 I have a 1997 fleetwood tioga class c. I thought I had really figured out this bus but just ran into a slight problem... I think! I'm hoping some of you folks can help me with this problem.
Getting ready for a short trip and started breaking down for the drive. while the mh was on our pad, I had the gray water pulled out for draining. I started running the water in the bathrm sink to put some water in the gray holding tank to flush the hose after the black water was dumped. Well, the black water tank started filling up and I quickly opened the black water valve and dumped the holding tank. I closed the bw valve and opened the gray water tank but nothing came out of the dump hose. This doesn't sound right! Am I missing something or is there something wrong with my sewer system?


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Re: dumping system
« Reply #1 on: July 23, 2017, 06:23:01 PM »
Some campers have the bathroom sink drain into the black tank instead of the gray tank. Sounds like that's how yours is set up.
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Rene T

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Re: dumping system
« Reply #2 on: July 23, 2017, 06:24:00 PM »
Shut all your drain valves. Then open up the one you think is for the toilet black tank. Then go in and run water down the toilet and see if water comes out of the drain valve you opened. If nothing come's out after a couple of minutes, shut it and open the other one which should be the gray tank. If water comes out, then they're labeled wrong.
Rene, Lucille & co-pilot Buddy
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Re: dumping system
« Reply #3 on: July 23, 2017, 06:54:16 PM »
As Happy said, some RV's do have the bathroom sink plumbed into the black tank. The rationale could be that it helps keep the black tank contents liquefied, but more likely it's because it saves the manufacturer a couple of bucks. The RVIA allows one other fixture besides the toilet to be connected to the black tank, but it cannot be the shower or tub.
2001 GBM Landau 34' Class A
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Re: dumping system
« Reply #4 on: July 23, 2017, 11:42:03 PM »
I have a much newer Tioga Class C, and I am pretty sure my sink is also connected to the black tank.  I have never tested it, but I hear gurgling in it sometimes when i flush the toilet.  I think they do it that way because it is closer to the black tank than the grey tank.

So, try running water through the kitchen sink.  I can guarantee that one is connected to the grey tank!  However, don't forget to make sure the plug in the sink is open.  I made that mistake once and flooded my kitchen floor. 
Full-timing for over six years in a
2012 Fleetwood Tioga Ranger 31N


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Re: dumping system
« Reply #5 on: July 24, 2017, 04:28:11 PM »
Thank you so much to all for the advise! I went out today and shut gray and black valves. I then ran water in the kitchen sink and, I believe you folks were right. Everything worked just fine. The gray tank filled to 1/4 and I opened the gray valve and it drained just fine. I then shut gray valve and ran water in the btrm sink and then opened the black water valve and it drained just fine so you folks were right! thanks again for the assistance.