Hi Cookie, and welcome to the forum.

It sure sounds to me like a venting problem.
Did someone flush the other toilet when you heard this?
Go pour more water slowly into the empty toilet and see if it sucks it down or not.
If not, leave it as it blocks sewer gasses from entering the home.

DM

 

Possible answer here: I have ran across a few, a small few at that, toilets where the "flapper" did not seal properly. Water would dribble through this flapper and normally this water would pass on through the bowl as it dribbled through. Case in point: A toilet that goes through one of those "1000 flush" cleaners in 2-3 days because of constant water flow. BUT--I have actually witnessed one in which the water coming into the toilet had to get to a certain height in order to drain, and this height was very close to the "flush height". When this one dribbled enough water into the bowl, it would flush by itself. This one took almost five hours to do a self-flush. Strange things can happen with crappers in life.

 

Strange things can happen with crappers in life.

So... crap happens? Po)

I see no reason why you wouldn't be able to use the other toilet.

DM

 

Hi,
No one flushed the other toilet. Is the other toilet ok to use right now? I also turned off the water in that bathroom (the one that flushed itself) I'll turn it back on. So does someone have to go on the roof and use a snake for the vent?
Thanks!

 

There's nothing wrong with your toilet. It's probably not a ventilation problem either. With the history of problems you've had, I'd be willing to bet the line was clogged again. It was a soft blockage that basically cleared itself. When it did, it sucked the toilet dry. Either that or the city came by with their jetter cleaning the city main. If conditions were right, the same thing could happen. I'm sure the plumber you called initially that jetted from the roof vent, didn't have anything to do with it not lasting as long either. The problem will continue until it's properly repaired. If you have the line cleared again, whether it lasts for 2 days or 2 years is merely a matter of anyone's speculation. It will also somewhat depend on the amount of use and/or abuse it's subjected to.

 

I agree with lateralconcepts
sounds like a clog. Last person to do number 2 didn't flush twice when they saw the contents not going down properly. ( think about getting a plumber's helper) Then the items in question did break free and used the toilet as a vent because of a possible blockage above the toilet drain. Suction from the passage of black water thru the pipe draining down to the sewer or septic sucked the water out of the toilet and caused the noise you heard. Falling water created a vacumn and in turn pulled the water from the bowl down with it cause it couldn't get the air it needed from the vent. If the other toilet is working properly then it might be on it's own vent pipe and it is safe from the clog. If they are back to back then the clog may be right at the connection. Sounds like the problem could still be there but worry only if this problem persists. Might just have been a one time issue. Or the passage is still partially clogged and could use some help. Just follow DangerMouse's advice and make sure there is water in the bowl to keep sewer gases from entering the house. Turning off the water will not have any positve effect. The tank has a device called a flapper that seats at the bottom of the bowl and holds back the water in the bowl until it is flushed and then it releases enough water to start the siphon process to normally flush a toilet. Remeber, a toilet should drain quickly and cleanly if the items are not of sufficient mass to cause blockage and the vent and drain pipes are not restricted.

Walt

 

I disagree with everyone that thinks its a vent or clog problem.
I think Thurman got it right. If a toilet fills with enough water it will flush itself. If this is correct, you have good news. $20 a beer and an hour, you can swap out all the guts of your toilet, or maybe 2 hours if you've never done it, but first try just a new flapper. Turn your toilet back on, if a while after you flush you see ripples in the bowl, you got a bad flapper seal.

 

Sound good Michael. Tell her to put some dye in the tank and see if it's leaking to the bowl..

For drain cleaner I use bleach. Add a quart at bed time and wake up to healthy drains. Just don't use too much bleach if you have a septic tank. I put less than 3 gallons per year in my 1500 gallon tank. Of course you know, I can get the 12% bleach.

 

Sounds like the BF is going to get the sort of news I hate to get when I get home from work.

 

Thanks for everyones reply. The toilet seems to be working fine now. My bf came home early from work and one of his friends told him it could have been from a clog in the ventilation cause we had heavy rain last night and it just unclogged itself.