I have a 2017 29.3 and the santi flush sometimes take a while to see water coming out due to water pressure at the dump station. Or there is no water pressure at all. We have seen this quite a few times. But we were told to let it fill a bit and then dump the water. Using Dawn helps a lot with smell and somewhat getting the tank clean. As of late, I've been dumping the tanks and then adding some clean water, say 5 gals, and then add in some Happy Camper chemicals. This really helps dissolve any solid waste left.
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