Anybody know what this is??

[Nick Welty]

This is a picture of the top fittings of a hydro massage pump under a large corner tub. I have seen many pumps before, but none with this "add-on" contraption. It would appear to be some sort of hook-up for a filter or cleanout attachment. Any ideas?

[A.D. Miller]

Who is the tub manufacturer?:confused:

[Jeff Remas]

Wow, look at the "do not wave hello" sign. Must be a strict factory where they assemble the parts.

[Jim Luttrall]

Certified WAG - air admittance valve to allow lines to be self draining.

[Jim Robinson]

I was guessing air admittance for the pump, to allow air in for the jets and bubbles. I see larger ones on outdoor hot tubs.

[Jim Luttrall]

I see two questionable items, the clear valve on top of the line connections and the tube strapped to the lines. The top could be a type of AAV for drainage and with the tube being the inlet for the air to feed the jets. Again CWAG.

[Jerry Peck]

Guys, that would not be an AAV (air admittance valve) as those are specialized things for special purposes, and they only work on non-pressurized systems.

That would be (I suspect) an atmospheric vacuum release backflow preventer.

That would be to allow air into the system.

Referring to the clear plastic thing at the top.

[Nick Welty]

Well.... okay. But the red tip of the strapped hose appears to fit into valve atop the pump like some sort of add on assembly just not hooked up.