Slow main drain. A Mystery I Cannot Solve

[PhilL]

Hello all, thank you for your time. Here is my situation as best I can describe it.

Moved into new rental house last week, and was told one of two toilets did not work. I was able to solve this by cleaning the siphon jet with a long screw. The other issue was, a very slowly draining kitchen sink.

Also, strange gurgling noises each time someone flushed the other toilet from all the drains in the house.

The other day, I plunged the sink with great force (the trap and pathway from drain to trap was spotless) and it didn't do anything. On my 3rd vigorous attempt, I heard a "glug glug glug" sound from all the drains and the double sink emptied out with zero delay. All was fine. Or so I thought.

The next day, I woke up and my toilet bowl didn't have any water in the bowl. When I went to flush, the water rose to the rim, but didn't drain. It slowly drained over the course of a day, kitchen sink also clogged again.

So I spend hours reading and watching videos. And I come away with the conclusion that I have a clog or some type of blockage in my main sewer drain line.

BUT THEN, I was informed by a neighbor that it was snaked last year with a 100' powered line and there were no clogs.

He says its a pressure issue and you need an Air Remittance Valve.

What say the experts? Thank you so much for your time. God bless

Phil

P. S. Is this something I could do myself? I love to learn and do things myself but recognize that sometimes it's best to let experts handle things.

 

[Terry]

Normally plumbing have venting that goes through the roof. Looking outside, you should see some pipes going out the top of the roof there.

What you describe sounds more like a main line back up though.
Even an AAV (auto air vent) needs at least one vent through the roof to function correctly.

 

[Sponsor]

 

[PhilL]

I do not have these vents or any indoor venting I can see. The plumbing was renovated a few years back by someone who took a lot of shortcuts in every other part of the house. I'm sure this was no exception.

So next stop is YouTube videos on how to install a vent, right? Lol I don't have much money at all and calling someone isn't really an option.

 

[Jeff H Young]

You got plugged main drain/ sewer. Its not a vent issue (95 percent) . Thought you said rental unit? Your loosing me you go to rent a house and landlord tells you toilet don't work? Aren't rentals inhabitable there?

 

[PhilL]

I'm renting a place from a friend who is in a very tight spot financially because of Covid. Thank you so much for your input.

 

[Reach4]

So I spend hours reading and watching videos. And I come away with the conclusion that I have a clog or some type of blockage in my main sewer drain line.

BUT THEN, I was informed by a neighbor that it was snaked last year with a 100' powered line and there were no clogs.

He says its a pressure issue and you need an Air Remittance Valve.

A venting issue alone will not cause bad draining. I am not a pro.

I infer the house is connected to a sewer rather than a septic tank.

Pay attention to what the lowest drain is. Usually that would be a shower or tub, unless there is a basement.

No clogs last year doesn't mean no clogs now.

 

[PhilL]

Okay so about an hour after having a full toilet bowl, it's now down to just the very bottom part. If it was a main line clog, why would the levels drop beyond the usual minimum at random intervals? I'm sorry.. This honestly makes me want to go to school to learn about plumbing, it's so frustrating but so cool at the same time.

 

[Reach4]

Okay so about an hour after having a full toilet bowl, it's now down to just the very bottom part. If it was a main line clog, why would the levels drop beyond the usual minimum at random intervals?

At random intervals, without your attempting to flush the toilet?

 

[PhilL]

Correct. It was filled to almost the brim. No leaks. I came back an hour later and the water has fallen to where there just a little bit in the very bottom cup. Nowhere near where it sat normally in the few days I was using it without incident.

 

[PhilL]

Also, the toilet is bubbling every 2 minutes for a 3 second duration. No one is using any water.

 

[Reach4]

Correct. It was filled to almost the brim. No leaks. I came back an hour later and the water has fallen to where there just a little bit in the very bottom cup. Nowhere near where it sat normally in the few days I was using it without incident.

Here is what I picture happening. The path through the toilet, or the pipe the toilet feeds into, became mostly clogged, and you then flushed. The water rose in the bowl.

If you use a plunger on the toilet vigorously, and the clog is below the toilet, you could create a lot of pressure. That pressure could blow out the wax seal. If the clog is in the toilet trapway, that should not happen. See https://terrylove.com/forums/index.php?threads/how-to-unclog-toilet.67075/#post-563093

Then the water siphoned out slowly (due to the clog). The water level went down and stayed down, because the refill tube had long ago stopped refilling the bowl.

A toilet is intended to siphon out, and the bowl refills as the tank refills. Normally the siphoning is fast, so the bowl can refill after the siphon has completed.

Now if you say the toilet can be sitting with the water at the normal level for a long while, and then without you touching the toilet, the level drops or bubbling starts, then that could be vent related... but that would also probably involve an additional problem.

 

[Jeff H Young]

Phil good friend you are to help your friend it sounded like a slumlord but I understand . its a drain stoppage not vent. So Id concentrate on all of the unknown age of property, sewer or septic? tree roots ? any clean outs to go down? clay pipe , cast iron, plastic? work that's been done history? you ever had it videoed?

 

[PhilL]

Phil good freind you are to help your freind it sounded like a slumlord but I understand . its a drain stoppage not vent. So Id concentrate on all of the unknown age of property, sewer or septic? tree roots ? any clean outs to go down? clay pipe , cast iron, plastic? work thats been done history? you ever had it videoed?

 

[JohnCT]

I am NOT a pro, but let me pass on a story that happened to me two years ago: I own a small 1950s block commercial building on a slab and both sides had backed up toilets. Plunging one side affected the other toilet, so we both plunged at the same time. No joy. I called a rooting service and waited. Meanwhile, before the rooter guy arrived, I located the trap under a storage bin and went outside to locate the vent, which was about 2' above the ground near the dumpster. I found the vent grate missing and also found some trash stuffed in it including a Gatorade bottle from the convenience store next to mine. I removed the garbage and heard water running. The rooter guy showed up at that point, we went inside, and both bowls flushed with a whoosh. The rooter guy flushed both at the same time and both flushed with authority. The rooter guy told me that a blocked vent could cause this problem. I realize there could have been a blockage that just disappeared on its own, but it really seemed like it was air bound. Just throwing that out there.

John

 

[Jeff H Young]

I am NOT a pro, but let me pass on a story that happened to me two years ago: I own a small 1950s block commercial building on a slab and both sides had backed up toilets. Plunging one side affected the other toilet, so we both plunged at the same time. No joy. I called a rooting service and waited. Meanwhile, before the rooter guy arrived, I located the trap under a storage bin and went outside to locate the vent, which was about 2' above the ground near the dumpster. I found the vent grate missing and also found some trash stuffed in it including a Gatorade bottle from the convenience store next to mine. I removed the garbage and heard water running. The rooter guy showed up at that point, we went inside, and both bowls flushed with a whoosh. The rooter guy flushed both at the same time and both flushed with authority. The rooter guy told me that a blocked vent could cause this problem. I realize there could have been a blockage that just disappeared on its own, but it really seemed like it was air bound. Just throwing that out there.

John

That sounds like a FAI for a building trap your toilets have vents that go out roof if its anything plumbed to any code in the country . I'm glad your case worked out , but in my experience and opinion I don't find your scenario likely. Me too just throwing that out we all want to help , at a certain point action needs to take place Just wondering What the op is trying? garden hose down vents? a bladder? rent a sewer snake? hire outfit to come out? or wait for it to go down.
Neighbor said someone ran 100 ft of cable. they didn't do that for nothing

 

[Reach4]

That sounds like a FAI for a building trap your toilets have vents that go out roof if its anything plumbed to any code in the country .

Good call. I think a building trap would change things significantly. I think those are supposed to be cleaned periodically.

 

[JohnCT]

That sounds like a FAI for a building trap ..

Good call Jeff: the vent in question was right at the corner of the building where the main trap is located so it does appear it's located above the trap. If that is the fresh air vent for the main trap, it couldn't cause a issue if plugged? Thanks.

John

 

[Jeff H Young]

Im not sure John. if only the vent was plugged i dont think it would though. in any case the OP probebly got a little head scratching figuring this out .
Phil any progress, sorry not helping much at this point