Since I need to contact Wunda about some dented UFH pipe they supplied, I thought I would also question them about the manifold they supplied. I noted this when I fixed it to the wall that a number of the flow guages were wet (You may just be able to make it out in the pic). I haven't plumbed anything in yet or pressure tested anything either. So, is it normal that these are sometimes wet? Packaging was all dry. I suspect that they perhaps test their manifolds at some point before shipping to the customer in which case that is fine.
I also purchased some acoustic ufh panels and noted that a number of these had scratches/dents and drips of plaster/paint on the foil layer in addition to coffee stains, so clearly these returns from another customer. So I may question them on that also whilst I'm at it. Not even as though these were discounted panels so a bit annoyed about that. So my overall thinking is that a lot of this stuff was returns from another customer including the manifold.
Maybe I'm just a fussy old git.