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LG dishwashers have a lot of moving parts that clean your kitchenware inside. Still, they’re not supposed to be noisy at all. Grinding or groaning noises from your dishwasher is abnormal and must be checked quickly.
Your LG dishwasher will make a grinding or groaning noise if the water inlet valve can only open partially. The noise comes from the water rushing in through a smaller-than-usual opening. Besides that, the drain or circulation pumps and their impellers are likely causes behind grinding and groaning noises.
You shouldn’t use your dishwasher if it’s making these noises. Instead, this guide will show you how to troubleshoot it immediately.
Why Is My LG Dishwasher Grinding Loudly?
Grinding noises in your dishwasher can be scary when you hear them for the first time. Still, there’s no need to panic.
Here’s what you need to know about the source of that grinding or groaning noise and what kind of fixes are needed:
Water Inlet Valve Issue
About this: The water inlet valve is the connecting point between the dishwasher and your household plumbing. It’s a mechanical valve that opens at the beginning of a new dishwashing cycle to let the water fill the appliance.
Once there’s enough water inside, the valve will shut entirely and stop any more water from entering.
Depending on your chosen cycle, you might hear the water inlet valve opening more than once. That will happen any time the appliance needs more clean water to function.
How it grinds or groans: A water inlet valve in excellent condition will open or close fully and never halfway. Unfortunately, you’ll hear the grinding or groaning sound when the valve is only partially open.
That partial opening forces the water to rush through only a tiny opening, which can cause the noises you hear.
How to fix it: Firstly, you must inspect the water inlet valve closely. A foreign object is likely to be stuck inside, preventing the valve from fully opening or closing.
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Besides that, you can also check around the valve’s openings for dirt, debris, or rust buildups. Those can also prevent the valve from opening and shutting correctly.
Foreign objects and buildups can be removed without much effort.
But if the valve is causing that noise because it’s faulty, you must replace it with a new one.
Read: 5 LG Dishwasher Problems You Need To Know
Circulation Pump Bearing Worn Out
About this: Your LG dishwasher has at least 2 water pumps inside. One is the circulation pump, which is crucial for cleaning your dishes.
As the name suggests, this pump is responsible for circulating water throughout your LG dishwasher. More specifically, it takes water in and drives it through the wash arms, so all your kitchenware gets washed.
The circulation pump spins an impeller at high speeds to make water move. That spinning is supported by bearings inside the motor that allow it to turn the impeller with no friction or noise being produced.
How it grinds or groans: The circulation pump will run throughout every wash cycle that you begin on your LG dishwasher. That means the pump and bearings are constantly under stress and will wear out with extended use.
When the bearings start to wear out, they’ll prevent the motor from turning the impeller smoothly and without noise. Instead, the motor will produce a grinding or groaning noise as it struggles to work correctly.
How to fix it: Unfortunately, the bearings inside the circulation pump motor can’t be replaced separately. So, if the one in your dishwasher is making lots of groaning and grinding noises, you’ll have to replace the entire pump with a new one.
Read: How To Fix LG Dishwasher Which Has No Power?
Drain Pump Bearing Worn Out
About this: Above, you read about two pumps in your LG dishwasher, with the circulation pump being one of them.
The second one is the drain pump, located at the bottom of the dishwasher. This pump helps to drive used water out of the appliance and into your household drain.
The pump will run any time the dishwasher empties before refilling with clean water. On top of that, it’ll also run one final time at the end of a cycle to remove all remaining water inside.
How it grinds or groans: Just like the circulation pump, the drain pump relies on bearings to spin an impeller. The bearings reduce friction so the motor can turn the impeller smoothly at high speeds without making noise.
Similarly, the bearings here can also wear out. When they do, you’ll hear grinding or groaning noises coming from this motor instead.
How to fix it: Sadly, you can’t repair or replace bearings in the drain pump motor separately either. So, you’ll have to replace the pump entirely if there’s a problem.
Be sure to test the pump thoroughly before spending money on a replacement.
You can try to turn the impeller manually to see if its movements are restricted by worn-out bearings.
Besides, you’ll also know the pump is the problem if the grinding and groaning noise only happens while the appliance drains.
Read: How To Fix LE Error Code On LG Dishwasher?
Jammed Pump Impeller
About this: The circulation and drain pumps consist of motors and bearings, as you’ve read above. However, they also have impellers that spin to drive water in a specific direction, whether towards the spinning wash arms or out through the drain.
Those impellers are kept in a very tight space within each pump. That way, they can pump water out with much more force.
How it grinds or groans: A final reason for the grinding and groaning you’ll want to consider is a jam in the pump impeller.
To clarify: the problem isn’t with the circulation or drain pump bearings. Instead, it’s with the impeller that the pump is trying to spin.
For example, a foreign object like a bone or stone might be stuck at the impeller, grinding against the pump’s inside.
As the part grinds against the turning impeller, it’ll create a loud grinding or groaning noise that you hear.
How to fix it: You might have a chance to save the affected drain or circulation pump if something is jamming its impeller. That will depend on whether or not you can get the foreign object out.
For instance, a single piece can be removed, and the pump will go back to working usually. However, if too many things are jammed inside, you’ll have to replace the entire pump.
Frequently Asked Questions (FAQs)
These are a few more questions and answers you’ll find helpful when troubleshooting your noisy LG dishwasher:
How Noisy Should A Dishwasher Be?
A dishwasher typically operates at 40-60 decibels, depending on the model. However, those noise levels aren’t very high. Instead, they are similar to the gentle humming noise that typically comes from your refrigerator.
Read: How To Reset CL Error Code On LG Dishwasher?
What Are Normal Dishwasher Noises?
Some normal dishwasher noises are the sounds of water swishing or rushing and a very gentle humming. However, grinding and groaning noises are not normal.
How Many Pumps Are There In A Dishwasher?
All dishwashers have at least two pumps. The first is the circulation pump that supplies water to the spray arms to clean your dishes. The second is the drain pump which removes used water from your dishwasher and drives it into your plumbing.
Read: How To Fix E1 Error Code On LG Dishwasher?
How Long Do LG Dishwashers Last?
You can expect your LG dishwasher to last 10-15 years with regular cleaning and maintenance. Typically, you’ll only face an increasing number of problems related to wear as the machine approaches the end of its lifespan.
Is It Worth It To Repair A 7-Year-Old Dishwasher?
You’ll have to see how much the repairs will cost. If the cost to repair that dishwasher is almost or over the price of a new dishwasher, you’re better off upgrading to a newer model with better features.
