Why does the sink gurgle when the washing machine drains?

The gurgling sound when the washing machine drains is normal as long as there is no underlying cause.

A Gurgling sound is generally heard when the air in the P-trap is displaced by the incoming water. Additionally, if there is a blockage in the drain line between the washer and the sink, this can also cause a gurgling sound as the water tries to flow through the blockage.

Why do you hear the gurgling sound when the washer drains?

This is quite familiar to a kitchen sink that gurgles due to clogging or heavy stuff being drained along with the waste.

When your washer drains out the wastewater, it drains out the mixture of detergents residue along with dirt and lint i.e. the tiny fibers from the clothes.

The pressure from the drain pump lets the flow move through the narrow drainpipe usually creating a gurgling sound while reaching the sink.

It may also occur due to air blocks in the vent areas of the sink.

If the gurgle is unusual, then it is the right time to have a look at the sewage area of the sink for any blockages.

The sink and the sewage area inspection is preferred by an expert or the plumber, as it may require sewage drilling equipment.

Most of you may have the washer’s drain connected to your kitchen sink which is quite common, here it becomes difficult to identify the cause of blockage caused, either by the washer or the kitchen waste.

If possible, it is always a good idea to separate the drain connection of the washer from other sinks.

That being said, here are a few possible causes why your sink gurgles when the washing machine drains.

Shared Drain Lines

If the washing machine and kitchen sink share drain lines, the gurgling may occur.

This setup is common to reduce piping and labor costs.

However, if there’s a blockage in the shared drain lines, it can impede the water flow, leading to the gurgling noise.

Blockage in Drain Lines

When the washing machine drains water at a high volume, a blockage in the drain lines shared with the sink can hinder the water’s smooth flow.

This obstruction may cause the gurgling noise as the water struggles to pass through the pipes.

Obstructed Venting System

The plumbing system includes a venting pipe that allows air into the pipes, ensuring smooth water flow.

If this venting system is partially obstructed, it can result in sluggish draining and noisy gurgling sounds.

Proper venting is crucial for the efficient operation of plumbing fixtures, including washing machines.

Ok, now that you know what causes a gurgling sound when the washing machine drains, let’s take a quick look at some basic steps you can take to fix it.

Also Read: How to Calculate washing machine capacity?

How do I fix the gurgling sound in sink?

A normal gurgling sound will be heard while your washer is draining due to the water flow pressure created by the drain pump. If you still want to make sure of any damages or causes of unusual gurgling sounds, then you may check out the below points. 

Also Read: How get rid of the smell from washing machine?

Use Drain Clearing Solution

There are chemicals available online or at the local hardware stores which can be simply poured over the sink filter (net filters made up of steel).

It comes in liquid and powdered forms, these chemical solutions require a lot of caution due to the highly concentrated ingredients used.

Hence it is recommended to always use protective gloves, wear a mask to cover your mouth and nose, and also wear a clear glass to protect your eyes.

Note: If you are using a chemical solution to unblock the vents, make sure the vent pipes are either made up of metals or reinforced concrete. Using this method on soft plastic pipes may cause unwanted damage.

Also Read: How to reduce noise from the washing machine?

Use Enzyme-Based Cleaner for Main Drain Line Obstructions

Enzyme-based cleaners contain natural enzymes and bacteria that feed on organic matter, such as grease, soap, and other debris, commonly found in drain lines.

These cleaners are environmentally friendly and provide a biological approach to breaking down and digesting the blockage.

How does the Enzyme-based cleaner work?

When poured down the drain, the enzymes in the cleaner work to break down and digest the accumulated organic materials that may be causing the obstruction in the main drain line.

This process is gradual but effective, targeting the source of the blockage without resorting to harsh chemicals.

Are Enzyme-based cleaners safe for plumbing?

Enzyme-based cleaners are generally safe for pipes and plumbing systems. Unlike some chemical drain cleaners that may be corrosive, the biological action of enzymes poses minimal risk of damage to pipes. This makes them a preferred choice for regular maintenance without compromising the integrity of the plumbing.

Preventive Maintenance using enzyme-based cleaners

Beyond addressing existing obstructions, enzyme-based cleaners are also valuable for preventive maintenance.

Regular use of these cleaners can help keep drain lines clear of build-ups, reducing the likelihood of gurgling and ensuring smooth water flow from the washing machine.

Call A Professional Plumber

A plumber or an expert would be the right person to determine the cause of the gurgling sound from the sink. Accordingly, a fix is recommended depending on the severity of a clog or it may be due to inappropriate installation. 

Also Read: 16 things you must know about washing machine drum?

Why is my washer not draining?

Either the drain pipe has been blocked or the drain pump is not functional. Clean the drain filter and the drain pipe for any clogs and try again. On the other hand, if the drain pump is not working then you may need a replacement or get an expert to check for any loose connections within the washer.

Also Read: 20 Things you must know about Dryers and Vents

Why does the sink fill with water when my washer drains?

You may need to check for obstacles blocking the sink vent immediately, as this may cause damage to your washer. The drain pump will have to bear immense pressure to push the water flow towards the clogged sink’s vent, this can also result in a burnt motor at times.

Also Read: How to Use Affresh Washing Machine Cleaner?

Final thoughts

Next time when you hear the normal gurgling sound, I am sure you know what to do in order to fix it.

Regular cleaning of vents and the drain systems in your household is always a good idea.

Lastly, do not hesitate to seek a piece of expert advice when it comes to plumbing fixtures.

Also Read: Are Washing Machines Waterproof on the outside?

Manish Singh is an expert in electrical engineering with a Diploma in the field. With over 12 years of experience, he specializes in repairing music systems, washing machines, dryers, and other laundry-related appliances. His in-depth knowledge in electrical repairs and decent knowledge about garment care makes him a trusted authority in the field of appliance repair and laundry related topics. If you have any questions or need assistance with your appliances, you can reach out to Manish through email: manish.singh (at) portablelaundry.com