In this post, I outline how I cleared my sink drain blockage that had persisted even with clear pipes. But first, I narrate my sad story. I was almost going insane due to the bathroom sink that had blocked for about a week. My kids and I had already started using a basin to take our shower. ????
By this time, I had called my plumber numerous times, but he was not available as it was Christmas times. My plumbing snake, drain cleaners, and hot water, the wet-dry vacuum cleaner was not working.
I had disconnected the u-bend under the sink and tried using a wire coat hanger to clear any drain clog, all with no success.
Summary: Assuming that the waste line sits at a small decline, you’ll need to solve a possible airflow issue for your vent stack. This will keep neutral air pressure (prevent negative or positive pressure).
Thus, wastewater will flow down the drain with the help of gravity. You should know that the toilet waste line and the sink waste lines are connected at their vent stack.
Sink Not Draining But Pipes Clear
My issue was that maybe I had a more significant problem because, in the previous three months, I had just miraculously unclogged my stubborn bathtub that had standing water.
What is vent stack? Where is it, and how can I check/fix it?
Vent stack blocked? The gurgling sound usually means it is “starving” for air. Without venting, the flush operation would act as a vacuum and would not properly flush.
The vent stack is usually hidden behind the wall. It is a vertical pipe to which all the drains along with that line tie into. Check the toilet too to make sure there is no partial blockage. Does the sink do anything funny also?
Check if the vent stack opening up on the roof?
Maybe yes? It is a black pipe that extends past the roof and is open at the top allowing rain to enter. So perhaps some rain froze on the lip and is restricting the opening of the pipe.
I have the same problem since installing new efficient flush toilets. If a vacuum created could cause p-traps to dry out or the toilet bowl level to drop when not in use? ( no leaks).
Raps should NEVER be dry!! Sewer gases can enter your home. In general, if there is a vacuum in the line, it can suck the water out of your traps and drop the toilet water level.
Read Also: Is drain cleaner acid or base?
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