Why Is My Dishwasher Making a Loud Noise? Check These 5 Things

Is your dishwasher making loud and unusual noises? Dishwashers are a regularly used appliance in both commercial and home kitchens, so detecting early warnings of mechanical issues early on can save you from expensive repairs, water damage, and additional hassle down the line. 

Here’s how to identify dishwasher noises you shouldn’t ignore and troubleshooting steps to address them before the problem escalates. 

How To Identify Noise From Your Dishwasher and What It Means

It’s normal for your dishwasher to make noises during operation. A steady humming from the motor, water splashing against the plates, and clicking during changes in the cycle, are all to be expected. 

However, if you notice noises coming from your dishwasher that weren’t present in previous cycles, especially if it’s loud, inconsistent in volume, and occurs unpredictably, this could be a cause for concern. These are some noises that indicate a problem with the dishwasher:  

• High-pitched squealing or whining: usually caused by loose belts, debris obstructions in the pump impeller, or faulty pump bearings.  
• Intermittent clicking: usually caused by electrical problems from the control board, or a malfunctioning water inlet valve, especially when the clicking is loud or irregular. 
• Thumping or banging: usually caused by unstable or broken spray arms or improper loading of the dishes in the dishwasher. 
• Humming or buzzing: usually caused by a straining pump or a blocked drain hose, which prevents water from flowing normally. 
• Scratching or grinding: usually caused by faulty motor bearings or foreign debris trapped in the filter or pump.

How To Fix a Dishwasher That Is Making Noise

Once you’ve identified the type of noise produced by your dishwasher, you can do a systematic examination of critical components most likely to be at fault. Note down when the noise occurs, whether it’s during the filling, washing, or draining cycle, and try to narrow down the sound to a specific area within the dishwasher. 

1. Check The Drain Pump

The drain pump is responsible for forcing dirty water out of the appliance. Loud noises like grinding or humming indicate a faulty pump. Check for blockages in the drain hose and pump, clean out the filter, and if needed, use a multimeter to determine if it needs to be replaced. 

2. Check The Spray Arms

If the spray arms are shaky, they can wobble and strike dishes during operation which results in thumping or banging sounds. Check the spray arms for looseness or damage, clean debris around it, and ensure they are firmly screwed or clicked into the nozzle. If they’re broken, replace them. 

3. Check The Impellers 

Impellers drive water into the spray arms and expels water from the unit. When they are broken, this can cause a squealing or grinding noise. You may also notice standing water that doesn’t drain properly. Replace either impeller if you notice cracks or damage and if they don’t turn normally with manual rotation. 

4. Check The Inlet Water Valve 

The inlet water valve can make screeching or buzzing sounds near the start of a cycle if there’s a blockage leading to restricted water flow or mineral buildup. A failure in the valve mechanism can also cause a loud humming sound as the valve is trying to open. Clean the valve screen thoroughly to remove food debris. Check the valve for rust and corrosion, and use a multimeter to determine if it needs to be replaced. 

Other Reasons Why Your Dishwasher Is Making a Loud Noise

There are also other less common reasons why your dishwasher may be making a loud noise. Before you call a professional, double check your dishwasher with these tips:

• Your dishes are loaded too close to each other, which causes the spray arms to hit dishes or utensil holders. Follow dishwasher loading best practices and do multiple rounds of washing if you have a lot to clean.  
• Worn or damaged dish rack rollers can vibrate or grind when the water pressure from the spray arms hit it. If you notice they’re warped, cracked, or broken, replace them immediately.
• A damaged dishwasher belt can cause loud noises during operation, so replace them if you notice slackness, cracks, or fraying. 
• Worn down motor bearings can create grinding sounds as the metal rubs against each other, so replace them if you notice excess heat or shaky equipment. 

How To Prevent Noises From Your Dishwasher 

Proper maintenance can ensure that unnatural noises from your dishwasher are kept to a minimum. Aim to clean and carry out routine inspections at least once every 2-3 months, and do it more if you use the appliance very often. Check for unusual wear and tear, loose or broken components, and clean filters regularly to remove food debris buildup. 

With regular care, your dishwasher will be better equipped to handle operations without breaking down. If you notice critical danger signs like smoke, a burning smell, visible cracks on the outside or in the tub, and electrical shock, stop use immediately and unplug the dishwasher from the power source. You will need to get assistance from a dishwasher repair technician. 

Final Thoughts 

Timely troubleshooting is crucial to get your dishwasher back to normal quickly. Because dishwashers operate using a complex system of parts, it can be tricky to identify and fix the cause of the noise. 

By identifying the type of noise it is and when it occurs during operation, you will be better equipped to fix the problem. In most cases, repair and replacement can be done by yourself, but if in doubt, call a repair technician to help you with multiple component breakdown or if you notice danger signs from your dishwasher.