Originally Posted by jrwalkerpa1
Yep. Most likely low point drain. Mine does the same....I can tighten it and it is ok for a while then vibrates loose. Seems to leak worse when water pump is on but that does not really make logical sense. I have it on my list to put real valves on mine soon.
Nah, leaking more with the water pump on makes perfect sense. You've generally got higher PSI from the water pump than you do in city water, if you're using a basic regulator.
But to the OP's question, I can't tell if that has a cap or not in that video. In total I see 3 drain holes under there, one flush to the bottom, one with no cap, and the one in black that's dripping. The dripping one could be low point drain, if that's cap. Otherwise, that might be a drain tube from a fridge.
The other two drains appear to be the ones to route water away from a slide? If it's like mine, there's a eaves tough just inside the slideout opening to catch leaks or whatnot and route that away.