Why Does Your Sink/Tub Gurgles When The Washing Machine Drains? [Explained with Fixes]
Are gurgles drained from the sink or bath tub as the laundry machine removes the water? Although most people disregard this, some homeowners are very perplexed about what triggers the creation of bubbles and the sound of ‘gur gur’ emanating from the drain of the sink/tub. If you are an astute analyst of things and want to know why sink gurgling arises due to the runoff of the washer, we are here to answer your question and give these enigmatic burbles a remedy.
Why My Sink Gurgles When The Washing Machine Drains Water?
This happens because your sink, tub, and the washing machine – all share the same drainage pipe for draining the water. The moment the washing machine releases a huge volume of water down the drain, the water pushes the air into the pipes and the air exits at sink or tub creating gurgling noises. Simply stated, the gurgling is attributed to the difference in pressure within the drain pipe that is shared by your laundry machine and your sink or shower.
Now there are several reasons for this pressure difference and the solutions:
1). A clogged vent.
If airflow is blocked, negative pressure draws air from everywhere it can. When water passes into the drain pipes, it creates an airtight seal. As water moves, air is pushed and a vacuum is formed. This vacuum is strong enough to pull air through the sink, or bathtub drain, and generate the guttural growl. A gurgling toilet normally implies that the vacuum is forcing water out of the toilet trap and the space may be swamped with sewage gas. To clear a clogged vent, inject a jet of water into the central vent stack.
2). The sink and/or tub vent is not installed properly.
Flawed installation of the sink vent is also a factor that could trigger your sink to gurgle. If the sink contains 1 ½ inch drain tubing, so the vent must be at least 3 ½ feet away from the bottom of the trap.
If this is not the case, the vent would not be able to drain enough air out and this would cause a pressure gap inside the plumbing framework.
The laundry machine emits water at an immense pressure. The vent will not be able to control the pressure enough, causing the sink to gurgle.
If the vent is located higher than 3 ½ feet from the trap, vacuum would be produced within the drain pipes. This vacuum effect causes your sink to gurgle because it pushes the air through the sink drain.
3). There is vent leakage.
if the sink vent is leaking, this indicates that the pressure present is poor and air cannot reach the vent, so it begins leaking through the sink drains. Low pressure and the vacuum effect can produce a gurgling sound within your sink.
4). The washing machine drain is using your kitchen sink as a vent to relief pressure in drains.
Some plumbing systems aren’t vented. If you look at those pipes under your sink and at no point do you see any pipe going inside the wall nor do you see a portion that is going to the attic, it means the vent is not there.
The vent pipe is identical in appearance to the pipe of the sink drain. The drain pipe passes underground within the wall, whilst the vent pipe heads to the attic and exits on the roof. When the laundry machine pumps water into the drain hose, the air enters in so the vacuum is generated in the pipe. If there’s no vent outlet, air enters from the opening of the kitchen sink. Therefore, air will only be sucked from the kitchen sink, causing gurgling.
Simply install a cheater vent and get rid of this gurgling sound.
5). The main drain line is partially blocked.
If you think the key source of water in the house is obstructed, you can attempt to repair the obstacle yourself. An enzyme-based drain cleaner is the safest alternative. The cleaner may be purchased at a Home Depot shop. Place it in the kitchen sink, the drain for the washer and the drain for the bathtub. Do this at night when you are not planning to use the sinks and the toilet. As long as practicable, let the enzyme cleaner stay and repeat several times. If the source of your gurgling problem was a partially blocked sewage pipe, you would begin to see changes.
When the gurgling ceases, every 3 months or so, it is best to start using the cleaner because you will have no issues. It is possible to use most industrial cleaners daily. The enzymes help to break down the soap and organic content in the drain line. This helps the sticky gunk and sludge to be washed out absolutely. It would open the drain lines and allow the waste water to run properly, so there will be no gurgling anymore.
So these are the causes and solutions to those sink/tub gurgles when the washing machine drains. First evaluate if your case falls in any of the aforementioned reasons, and then get started with the treatment.