My understanding is that the sink and shower are plumbed to the Waste Water valve at the bottom of the trailer as there is no grey tank. However, I saw someone mention that they drain in to the black tank. Can anyone confirm which is accurate? Also, if it does go in to black, is is possible for it to back up in to the shower or sink?
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it dose-not go into  black water tank. The tt that have both tanks use a common drain valve on some models. It is always wise to keep black water and gray water separate. The 150 and 155 only have 5 gal black water tank. So if you use the shower it would fill the tank. GBA!!SVJ
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