Bad venting?

It seems that after building my great vent without using a 'goof vent,' all PVC to vent stack, I wonder if I went too far?

The 1 1/2" vent runs horizontal to sink, then washing machine drain from higher than the utility sink drain.

I added a loop above the 4' high vent...going maybe 2.5' above (to go above a cabinet) and then over 5' to pick up the 'last vent,' that of the utility room sink.

First time I did the wash, I noticed a 'bad' smell, not terribly strong, but I'm sure it's vent gases getting trapped up in this higher section of vent pipe.

Is that gas going to do anything more than get my wife to yell at me? It won't build up any appreciable pressure and combust or explode, will it?

Or, do I really need to add a goof vent at the end of the line. Sorry, thought I was handy!

Doug

vent

If you did everything correctly, and it strains the brain trying to follow the path the way you describe it, then there should not be any odors.

Sorry, my brain went way past strain years ago.

I'm going to live with it...doesn't leak...drains at full bore and I'll have time to fix it if this is more than a glitch. Thanks again, hj...you've helped cover some nice nubie stuff with me!

Doug

I think he means it goes up, but then comes back down before connecting to the stack. Sort of an upside-down P trap, where gases collect... except there's a leak somewhere in it?

Frenchie said:

I think he means it goes up, but then comes back down before connecting to the stack. Sort of an upside-down P trap

Click to expand...

Yeah, but that doesn't explain the odor - must be something else wrong with it. BTW - the upside down p-trap thing? That's wrong.

In the basement I have a vent stack going up through the roof without anything above it.

I've got, in this order going to the stack...

A vent, utility sink drain, washer drain, sink drain with vent. When 'they' installed the washer downstairs, they worked in a wall and didn't or couldn't install a vent specifically for the washer.

The first vent listed above, goes up to the ceiling, over 5' horizontal and then comes down 3' to connect with the second vent, so there's a loop up high.

I obviously really don't know what I'm doing...but I'm good at it!

Every drain has a p-trap, though the washer isn't independently vented, I don't think, unless you count the gap between the washer drain hose and the 1 1/2 pvc it's stuck into. When the washer drains it will back up a little into the utility sink...is that a problem?

Sorry guys, don't worry if you can't figure this out...I will eventually! thanks for any thoughts!

Doug

Ah, I think because the washer doesn't have a vent, it's sucking the water out from the p-trap behind it in line, and that's allowing a 'burp' of sewer gases to come up from the utility sink.

The contractors burnt one of the fittings on the 'washer' service area and also put copper piping where a vent should have gone...will try to splice in to real vent. If I can't, is a goof vent acceptable or better than nothing and how high must it be relative to something else?

Doug

Thanks guys for all your thoughts, especially after my awkward attempt at writing instead of posting a photo.

...and just in case anyone is still reading here...am I correct in understanding that a vent line must always go up into the stack? I've got this one section that rises 3' straight up...about 6' downline from where I connect into the vent stack...no water ever gets up to that point anyway, so is that extra 'gas collecting' section impermissible?

Doug

From the point of connection to the roof outlet, the vent pipe should have some slope upwards so there can be no accumulation of water (say rain that ran down the pipe) that could block the movement of air like a secondary p-trap. If it makes loops, or has negative slope, you risk it being blocked and therefore no longer a vent.