Is it a gate valve on the street side? I don’t have your model but sometimes coaches with the bathroom on the right side will have two valves. The second one is there so that the, um, solids, in your holding tank won’t settle into a long drain pipe possibly clogging it with unpleasantness. Other coaches address this with a single valve that is on the right side but cable or pushrod operated. Each approach has its advantages and it’s disadvantages. Just one more thing to get used to.
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