Dumb question about washing machine outlet box

Hello,
I just moved into a fore closed home, that has two washing machine spaces. The upstairs one is installed working fine. This came with the house.
The downstairs one is the one we brought from our last house and we would like the use of it too (okay if you guys can help me out - it would help win some brownie points with the wife).

Here is my dumb question, the outlet box has two sealed tabs on the left and right and the cold and hot water, which is hooked up to our machine. The problem is the drain hole (I assume one of the two sealed tabs) is completely sealed (as I say), I thought maybe I could poke through with a knife, but its quite thick and I am not even sure if there is an actual drain there.

So specifically, how can I open up the hole (what's the best tool) and how can I be sure that there is drain there and I am not pumping water into the wall - that wouldn't be fun.

I am a bit of an amateur when it comes to plumbing, but I need to save money and don't like paying for a plumber.

Thanks
D

It might help if you'd post some pictures. Sight unseen, it's a bit difficult to make suggestions, but understand that the boxes are only for convenience. Each washer needs hot water and cold water faucets and a 2" drain that has a P trap, vent, and a connection to a sewage line. The vent and sewage line connection can be a problem especially for a novice. While it's not exactly brain surgery, it is a bit more involved that just gluing PVC pipe together. You can find photos and discussions on washer installations on this forum, but connect the drain to the sewer may be a problem for you.

hadfield43 said:

Hello,
I just moved into a fore closed home, that has two washing machine spaces. The upstairs one is installed working fine. This came with the house. The downstairs one is the one we brought from our last house and we would like the use of it too.

Click to expand...

How in the world do you bring a washing machine space from your last house?

I think they mean they brought their washing MACHINE from the other house. There is a pipe under ONE of those two openings. Unsnap the trim ring from the box and either slide a knife under the box or use a flashlight to see which of the two is connected. A hammer and screwdriver will remove the proper seal.

While HJ is probably right, some of the boxes have an optional matching piece to take the drain line. You might want to do this, for example, to have more room for the drain plumbing verses having both the water and drain in the same stud bay. They may have intended to use a utility sink to dump the WM outlet into rather than a dedicated standpipe and there's no drain in either spot. You'll only know if you look...

quote; They may have intended to use a utility sink to dump the WM outlet into rather than a dedicated standpipe and there's no drain in either spot.

IF that were the case, then there would be a sink drain out of the wall close by, along with hot and cold connections for the sink.