Water level dropping for 3 toilets on 2 different floors in my house.

[chrisbell86]

Hi, I live in a two story house with two toilets located upstairs, one downstairs. In Dec the sewer pipe to our home was clogged and was fixed by a plumber. No issues with the pipe after that, however about two weeks later we noticed that the water level in all of the toilets dropped by about an inch in each bowl. For the toilet that is used the least, it dropped about 2 inches.

I don't think unclogging the sewer pipe has anything to do with it, but wanted to include the information just in case. From everything I've read this appears to be a blocked vent. Does it sound like this could be the case?

Thank you in advance for any help or advice.

 

[WorthFlorida]

The water now drains faster than before which in itself is OK but it causes a higher negative pressure (vacuum) behind the flowing water. The higher atmospheric pressure inside the home pushes down on the water in the bowl. Probably less than a ounce at a time. It's why good venting is important. As you said, there could be some blocked venting. Fully blocked and you would hear gurgling from sinks drains and slow draining. My home built in 2007 uses mostly AAV's and there are one or two roof vents. I haven't yet figured it all out. My second floor bathroom the toilet bowl level will drop and I know for sure an AAV is used for that bathroom. Most of the time it's the 1st floor toilets that are flushed.

I remember as a kid in the home I grew up in, on extreme windy days, the bowl water level would go up and down. The wind blowing over the roof vent pipe was causing negative pressure in the vent pipe.

 

[Sponsor]

 

[chrisbell86]

Thank you for the info!