Why is water bubbling up in sink when water is released from upstairs sink?

When water is let out with stopper from upstairs sink, it immediately bubbles up in downstairs sink, what would be the problem?

7 Answers

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  • Anonymous
    4 months ago
    Favourite answer

    Not a problem.  They use the same drain pipe so you get air displacement.

  • 4 months ago

    the drain below the sink needs to be snaked out.  job for plumber and his powered snake which may have to be done from the roof vent

  • elhigh
    Lv 7
    4 months ago

    Sounds like you have a partial blockage in the drain further down the line from the downstairs sink.  Get that cleared up and you won't have backflow coming up its drain anymore.

  • Anonymous
    4 months ago

    Clogged vent or no vented 

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  • Anonymous
    4 months ago

    For that to happen in most situations the large diameter vertical pipe to which they are both connected is running full bore. Which means there is an obstruction somewhere. 

  • Anonymous
    4 months ago

    Could be a clogged drain or a clogged vent.  Call a plumber.

  • A.J.
    Lv 7
    4 months ago

    They must be on a common drain line that is slow or nearly blocked. Downstairs sink should show a slow drain.

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