Washing Machine Drain

[MikeM7]

My girlfriends washing machine drains into this contraption. The black hose leads to the machine. Does anyone know what this is? Is this a “cheater vent”?

I’m concerned that there is no way to catch the lint from the washing machine. She occasionally has minor sewer backups in the basement where dirty water will come up through the basement slopsink or through a floor drain. I wonder if this may have somthing to do with it.

 

[Silentrunning]

I have never seen a hookup like that. I am going to guess that top cap is some kind of vent.

 

[udraft]

I'm gonna guess that's a bit of plumbing left over from a no longer there fixture, like a sink or something. You could plumb a filter in there, but it would be better to power snake the drain, it should easily handle anything from a washer.

 

[cecwarrant]

That is a device to allow a drain to vent but close off when not venting. Similar but not same as a dishwater vent which is only a back-flow device. I do not remember the proper name for that device you show. It must be installed at the highest point of the system/sub-system. Installed like it is; if there is a sewer line backup like being experienced it will spill sewage, especially if the flapper valve is clogged or worn out. Installed like it is it is probably clogged up with lint balls as well as the rest of the drain line. This is a gross code violation; a washer drain is required to be at a 48 +/- " above the floor the machine is setting on. It is an open top drain with a trap at the bottom where it connects to a sewage line. That is why someone put in that venting device, bad move but cheaper than plumbing up through the wall. If worried about lint accumulation a clean out can be installed in the horizontal drain in the basement. That long hose with the loop in it isn't helping either.

Get Taunton's "Plumbing Complete" at Lowes or Home Depot to get the info to fix it right. If the house is a rental inform your landlord as it is also a sanitary issue you can get help from your local health department or building inspector.

Ron

 

[piglet11]

I agree with cecwarrant.
It looks like an air admittance device, otherwise known as a Durgo valve (Marley trade name)
Normally, the open soil pipe "stink pipe" provided the anti-vacuum ventilation to stop water traps being emptied in the event of low pressure (vacuum) in the sewer system. The valve has a very weak spring and flap valve and is not designed to hold back pressure in a waste system, only to open on reduced pressure. It should only be fitted above the highest waste outlet on the property, so unless the wasing machine is in the loft, it's a no-no and best removed. In any case, if it was acting as a whole house air-admittance device, it would be too small. Most vent pipes are 4 or 6-inch at least. As far as I know, a Durgo valve cannot be fitted at the head of a sewer branch, and then at only one in four of the properties on the branch. Professionaly, I never came across negative pressures in sewers (usually the other way round). About as risky as as negative pressure on mains water and the need to fit double check valves

 

[abraham5]

I guess the top cap is some kind of vent.