[denemante]

Hey all - I've posted similar topics before, but I'm starting fresh here because I seem to have isolated things a bit. Now that I've learned all about septic and learned the ins-and-outs of my system, I have more comfort with it. But there is one thing I can't figure out.

The basement toilet, which would appear to be the lowest drain in the home, occasionally "burps". This seems to happen when there are larger sums of water leaving the home via drains, like when someone showers upstairs or the washer is running. These are like single bubbles perhaps a little larger than golf balls coming back up the toilet every 3-5 second, with an audible noise. It only seems to last a short time. There is no smell.

So we figure it's a venting issue. There is a Studer (is that how you spell it?) vent on the toilet. There is also the same size Studer vent coming off the main house drain. Both are in my basement. I'm fairly certain there are no vents going out the top of the house.

What I'm trying to figure out is why this burping happens. I understand that if you try to pour liquid into a plastic bottle, air rushes out as water rushes in.

But that being said - since I believe the septic is a closed system, the air rushing out (and presumably finding the easiest exit out the basement toilet) should smell rank - yet it doesn't. Perhaps the toilet has swallowed clean air, the the "burps" are just what is near the toilet so somewhat "clean" smelling.

And the Studer vents are supposed to be one-way - so they would be dead-ends for air trying to escape.

I'm wondering if the air is supposed to be pushed deeper into the septic system and out in the fields to escape slowly, but something about the design isn't allowing that.

I and all my neighbors have soil issues we've learned to deal with. We moved in recently - but they've lived with it for 13 years. After heavy rain and when the ground is soaked and after water use, basement toilets won't flush. Give it a few hours or overnight - and everything is back to normal. Multiple professionals have told me "that's septic for you! Live with it!".

So the fields can't purge off liquids fast enough - but it seems they eventually do, and work fine 97% of the time.

Still - something is causing the burping. And it happens even after a long dry spell. I can live with it. But I hoping for advice as to whether it's a sign of a big future problem - or just the nature of my system.

Thanks.

 

[Just Bill]

I hate long posts, I tend to skim them for the actual question.

My first guess for the 'burping', is a vent problem. Clear large vents are necessary for all plumbing systems to function, it matters not where the other end goes. If the system can't get sufficient air from a vent, it finds it at sinks and toilets.

 

[denemante]

Thanks Bill,

Whoa - are you saying the toilet is not burping air out - but instead, sucking it in? That would make sense as to why there is no smell.

But is that possible? I mean, there are a few gallons of water or so in the toilet trap and bowl - could so much suction be being created within the system that it pulls on that toilet water so much it actually pulls air all the way through that water?

As noted, there is a Studer valve on that toilet as the vent. I think it's a 2.5 inch PVC pipe. Could putting a second one or a larger one on that help?

 

[AllanJ]

The upstairs plumbing is supposed to have its own vent, going up through the roof (or its own Studer vents).

You may need to have someone go up on the roof and see that this vent is not clogged.

 

[denemante]

Hmmm - I'll have to go outside or into the attic and look for the PVC vent.

Are you saying that if the upstairs was vented properly, perhaps the burp wouldn't happen in the basement since it's a closed system?

Or do you think by chance when the basement toilet was installed (when basement was finished a few years ago) - perhaps there is a trap or something that has separated that toilet from the rest of the plumbing, so instead of the whole system being vented as it should be - somehow, the easiest vent is now through the toilet?