Clogged vent stack

[wannabervin]

Toilet gives a big burn when flushing full bowl of water. I think my vent stack may be clogged. What is a safe way to unclog it?

 

[wannabervin]

I meant burb, of course, lol

 

[Hoopy Frood]

Burp?

 

[Chaps2018]

I thought mine was blocked one time too. I turned the flush port on and went up topside. Pulled the cap off the vent tube and took a peek, I was surprised to hear the water shooting into the black tank.

If you determine its blocked, you could (gently) use a snake down the vent pipe or shoot a water hose down it to clear the blockage.

 

[CedarCreekWoody]

Oh my. I misread your post and omitted the letter "k" from peek. That was a strange mental image! Lol

 

[Riverbug]

Remove the vent cover on the roof and pour a pitcher of water down. If it makes it to the tank, you don't have a clog. More likely you have an issue with the vent stack. Perhaps it slipped down into the tank. Ours was near the bottom of the tank from the factory. I chose to fix it myself, but you may want to verify what's happening and bring it in under warranty.

Assuming that you ruled out a clog in the vent stack, I think the best method to verify what is happening is to do the following: Flush the tank. Fill to about 20% with fresh water, check to see if it burps. Fill to about 40%, check again. Fill to 60%, etc. Continue until you figure out at what point it starts to burp. If it is less than nearly completely full, then you have an issue with the vent pipe sticking too far down into the tank. It is easiest to use a flow meter so you know how many gallons you are putting into the tank for this test. That way you can be sure of how full the tank is and at what point the bottom of the vent pipe is in the water. The other, less desirable, method is to flush the tank well, shut off the water, and stick an endoscope down into the toilet and locate the vent stack. You will be able to see if the pipe is sitting at the top of the tank as it should or if it is sticking too far down into the tank.

Good luck!

 

[Chaps2018]

Excellent diag strategy Riverbed!