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MarkRakowski
Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.

My father had a toilet replaced in his downstairs powder room recently. He noticed that the water in the toilet bowl dropped overnight. When he flushed the downstairs toilet, the water level in the bowl went back to normal.

I had him flush the upstairs bathroom toilet while I watched the one downstairs. When he did this, I noticed the water level in the downstairs toilet dropped. I suggested that there may be an obstruction in the vent stack and that flushing the upstairs toilet was causing the suctioning of the water from the downstairs toilet.

My father worked with the plumber that installed the new toilet and a contractor that went on the roof and cleaned the vent stacks. After the vent stack cleaning, flushing the upstairs toilet still suctions water from the downstairs toilet.

Looking for advice on what to try next.

HoustonRemodeler
Re: Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.

I'd look into re-routing the vent to the lowest toilet.

bill
Re: Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.

Definitely a venting problem. Is the lavatory sink in the bathroom vented? It should be. Sometimes in the middle of a cold winter a vent pipe such as the vent for the lavatory sink in that powder room will have a place where the water collects and freezes and then blocks the vent.

MarkRakowski
Re: Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.
bill shack wrote:

Definitely a venting problem. Is the lavatory sink in the bathroom vented? It should be. Sometimes in the middle of a cold winter a vent pipe such as the vent for the lavatory sink in that powder room will have a place where the water collects and freezes and then blocks the vent.

Both upstairs and down stairs bathroom/powder rooms have lavatory sinks which are vented through main stack as far as I can tell. Down stairs sink drain has been cleared. Will take a look at the upstairs sink drain. Thanks for suggestion.

MarkRakowski
Re: Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.
MarkRakowski wrote:

Both upstairs and down stairs bathroom/powder rooms have lavatory sinks which are vented through main stack as far as I can tell. Down stairs sink drain has been cleared. Will take a look at the upstairs sink drain. Thanks for suggestion.

Roto-rooter contacted to thoroughly clear vent stack. Problem resolved.

HoustonRemodeler
Re: Water pulled out of downstairs toilet bowl when upstairs toilet is flushed.

Thanks for the update

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