JackHoppus Report post Posted July 20, 2014 Hi everyone!I have a new to me 2011 Dutch Star after trading in my new Tiffin 36la gasser whose engine blew up! Tiffin wouldn't help.The DSDP has a tecma silence plus toilet with the two flush button.During the last few weeks that we have had it flushing the toilet, on 4 occasions, has produced a shot of water out the black vent pipe.....mostly clear but smelly. The toilet bowl was empty until I flushed it again.Did not refill on its own.Grey tank was open, black tank about half full, vent pipe was clear ( put hose down it and water came into black tank).Called Thetford and they said to keep gray tank closed unless dumping or using washer.Called Newmar and they told me the same thing!Says some pressure is being created???So....what do you all think?? Jack Share this post Link to post Share on other sites
hermanmullins Report post Posted July 20, 2014 Jack, Welcome to the Forum. For most folks the standard procedure is to keep both tank valves closed and to allow the Holding tank to get to at least 3/4 full. Then to drain the Holding tank first and close the valve then dump the Gray Water. This way the Holding tank will not allow solids to dry on the walls and bottom and the Gray Water will act as a flush or rinse for the hose. When you say that it is shooting water out the vent stack do you mean the vent on top of your coach? Does it happen only when the toilet is flushed? Being that it is clear but smelly appears to me to be the Gray Water. Do you only have one vent where both tanks are vented together or is there a vent for each tank? It seems that there is a back pressure coming from some where. Have you called the tank manufacturer? You might start there and see if they might have a suggestion. Herman Share this post Link to post Share on other sites
JackHoppus Report post Posted July 20, 2014 Thanks for the welcome Herman ! Yes, the water is coming out of the vent pipe on the roof. There are two vents, one directly on top of the wet bay and another in the right rear corner of the roof. It only happens when the toilet is flushed.....but doesn't happen every time, and the grey tank open. I am assuming the vent over the wet bay is from the black tank. We ran a hose into that vent and the water came into the black tank. I only called thetford and Newmar and they told me to keep the grey tank closed. What I don't understand is how the grey tank being open or closed can create pressure in the black tank?????? Jack Share this post Link to post Share on other sites
