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 toilets syphon water from each other
Author: cft (OH)

We just had 2 new toilets installed in different bathrooms but in a back to back orientation on a dividing wall.
When we flush one toilet, water is syphoned from the other toilet, about a 1/4 inch per flush...no leaks on floor just water level is lowered.
Our plumber has no idea what to do.
Anyone have any ideas?

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 Re: toilets syphon water from each other
Author: KCRoto (MO)

If water is being siphoned, then you have insufficient venting. As the water passes down the pipe, the pressure differential is causing a vacuum in the opposite toilet. Normally, the vent would compensate and provide the air that the drain requires, but it is instead drawing through the other toilet. I am guessing that there isn't a vent until you get to the sinks at least, or it would probably be sucking the traps dry with them as well.

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 Re: toilets syphon water from each other
Author: packy (MA)

Anything fall down the pipes during replacement?

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 Re: toilets syphon water from each other
Author: hj (AZ)

How are they connected to the main line?

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 Re: toilets syphon water from each other
Author: bernabeu (SC)

proper back-to-back venting:



= = = = = = = = =

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

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 Re: toilets syphon water from each other
Author: hj (AZ)

The question is "HOW are the back to back toilets connected". Your drawing shows a sanitary cross, and I do not know any code that would accept that.

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 Re: toilets syphon water from each other
Author: bernabeu (SC)

I forget the vernacular, but there are / were 'baffled' fittings specifically for the purpose.

The point of the drawing was to show the proper venting.

= = = = = = = = =

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

Post Reply

 Re: toilets syphon water from each other
Author: hj (AZ)

quote; but there are / were 'baffled' fittings specifically for the purpose.

Now, you are going back a long, long ways and they were cast iron, usually referred to as "Stringer fittings" because that was the name of the patented line of specific use fittings.

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 Re: toilets syphon water from each other
Author: bernabeu (SC)

... yep, I am older than dirt

older than the rocks that eventually FORM the dirt


frowning

= = = = = = = = =

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

Post Reply





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