Is this a pressure valve?

Hi

I am rebuilding my laundry space and came upon this construct that is inserted in the cold water supply line. The whole ting looks like a later addition and was built outside the drywall behind the washer (see photos)

I would like to remove the parts that were built outside the drywall, but I don't know what the function or the other side connection is of the line coming off the cold water supply line. My guess is that this is a pressure relief and the 1/2": pipe coming down is to catch moisture. The fact that the device has a slot in it that sits just above the auction with this 1/2" pipe coming down (see close up picture) leads me to believe that this pipe is open at the top, but I cannot be sure without taking it apart.
So if this were intended to catch liquid when the valve released pressure (assuming it is a pressure valve) I do not understand why it does not go to a drain nearby that was installed to catch whaling machine leaks. It goes into the wall and then down into the floor, but there is nothing in the floor below.


So, 1) is this a pressure valve? Or is it a hammer arrestor (old style)
2) Is the pipe running down from the device under pressure
3) Where would it typically go? Waste or supply? (i.e. pressure or no pressure)
3) Can I just cut this pipe and cap it, and connect the cold water supply without it
4) Do I have to insert a better placed new pressure valve (or whatever its function was?)

Any help and suggestions are greatly appreciated

Ronald

Looks like some kind of mixing valve

Pressure balancing maybe?

It is a trap primer.

Thats a mifab mi-tsp-2 trap seal primer. It should be made easily accessable for service, not buried behind drywall.

It's going to a floor drain most likely.

johnjh2o said:

It is a trap primer.

Click to expand...

Bingo we have a wiener....winner

Thanks to everyone who correctly identified this as a trap seal primer. Once you know it you can easily find the picture of this MIFAB (flow) trap primer online.

I had a local plumber look at this and he did not have a clue even though I showed him the floor drain that was under the washing machine and pointed out that this was apparently a connected, working drain, because I noted water in the P-trap. He figured the device may have been a pressure valve and was planning to disconnect it from the washer supply line. We would have had bad smells sooner or later.

So now I will replace it with a pressure activated MIFAB MR500 in the branch I going to make to a small sink next to the washing machine. I am going to recess it in the wall, to get more space for the washer, but keep it serviceable. The MR500 suits be better than the current one because it uses threaded connectors and is thus more easily replaced.

Thanks and until the next plumbing surprise ,

Ronald

Good call on the trap primer would have been helpful to know there was a floor drain