floor u-bend

[drestie]

I do not know anything about plumbing, so I apologise if this is a stupid question...

I just moved in to a 6th floor condo. In the laundry room, there is a drain in the middle of the floor. The surveyor told me to always keep water inside so that it doesn't dry out and allow sewer smells to come up.

So my question is what is that drain for? If it's for catching water if the washer overflows, how can it do that if it is sitting full of water constantly?
Will additional water draining in push the original water down, or will it just overflow?

Adding a cup of water today just raised the water level in the pipe almost to the floor level, so I am confused :(

Any comments welcome!!

[dot.hawkes]

Not a clue I am rubbish at plumbing issues

[Clanad]

What he's saying is that under the floor just below what you can see as the entry to the drain is a "gooseneck"... a part of the drain pipe shaped somewhat like an "S" on its side. the lower part of that "S" traps water and keeps sewer gasses from coming up. On drains that aren't used very often (the one under your sink is used several times a day) can dry out from evaporation and let the gasses come up. Keep pouring some water in it... probably once or twice a week is sufficient. Building codes, at least here in the U.S., require a drain in a basement floor for several good reasons, not the least is to have a place for overflows from washers or hot water heaters to go...

[carrust]

As it's in a laundry room I summise it's a drain to allow water to escape if the washing machine overflows. It will work on the same principle as a trap on a sink or the U bend on a toilet. Added water will drain away into a pipe under the floor & then into the mains drainage. Hope this helps.

[drestie]

Thanks all, but why doesn't it drain at all if I add more water to it? It just fills all the way up to the top.
Is it possibly just clogged?

P.S. Hiya Clanad :)

[Clanad]

It could be clogged, drestie (didn't look at the submitter). Floor drains are notorius for clogging due to all the junk that goes down them. You could try removing the drain top. It should be (if similar to ours) a perforated "cap" on it and is held in place by a couple of screws. Then you can run a coat hanger into it to tee if you can get it to drain. Failing that, call a plumber... Good luck!

[drestie]

Thanks, Clanad.

So it should drain normally, right?
Will try the coat hanger trick tomorrow. The cap isn't even screwed in - it pops right off.
The condo rules prohibit using drano, so if the hanger doesn't work I will have to call a plumber.

Thanks again!

[heathfield]

Or a rubber plunger might clear it.

[drestie]

Thanks, heathfield. Will try that tomorrow too!