Sewer Vent Question

[JustAGuy85]

So we remodeled our master bathroom and the shower turned out great. Working and draining perfectly.

Fast forward a week and I decide instead of using a shallow electrical box for a vanity light in front of the drain pipe that putting four 90 degree turns was a better solution. Now I know that likely wasn’t my best bet.

Anyway, I had no additional horizontal run on the sewer vent pipe, but it seems to have created a negative pressure situation. The shower would drain fine for a minute then back up and drain ever so slowly.

I’ve now recoupled the 1.5” vent pipe to recreate the straight run up and out of the roof. It seems to have extended the time it takes for the drain to start backing up (2-3 minutes) but it eventually does back up.

Can anybody tell me what I’m likely missing here? The drop on the shower drain is fine. I left it as existing and double checked it all with a level before closing up the floor. It also ran fine for a week. Is it possible I’m missing the forest for the trees here? No other drains are backed up in the house, granted I don’t have the vanities or toilet hooked up yet in that bathroom.

Thanks!

 

[Jeff H Young]

youve got a drain stoppage . lets clarify to be sure you put 4 90s to offset around a light fixture you said it was a drain pipe ? Im thinking it was a vent but going with your description of it being a drain . so this drain is for a shower on the master bedroom on the floor above ? then you say you recoupled a vent pipe a bit confusing to me ?
sounds like you have plugged drain pipe to me but im pretty sure the story is inaccurate so I cant give best advice

 

[Sponsor]

 

[Jeff H Young]

So we remodeled our master bathroom and the shower turned out great. Working and draining perfectly.

Fast forward a week and I decide instead of using a shallow electrical box for a vanity light in front of the drain pipe that putting four 90 degree turns was a better solution. Now I know that likely wasn’t my best bet.

Anyway, I had no additional horizontal run on the sewer vent pipe, but it seems to have created a negative pressure situation. The shower would drain fine for a minute then back up and drain ever so slowly.

I’ve now recoupled the 1.5” vent pipe to recreate the straight run up and out of the roof. It seems to have extended the time it takes for the drain to start backing up (2-3 minutes) but it eventually does back up.

Can anybody tell me what I’m likely missing here? The drop on the shower drain is fine. I left it as existing and double checked it all with a level before closing up the floor. It also ran fine for a week. Is it possible I’m missing the forest for the trees here? No other drains are backed up in the house, granted I don’t have the vanities or toilet hooked up yet in that bathroom.

Thanks!

all fixed yet?