Why Is My Commercial Glasswasher Making a Strange Noise?

A commercial glasswasher contains several components capable of producing noise during normal operation.

Depending on the machine, these can include:

• Wash pump

• Drain pump

• Rinse pump

• Wash arms

• Rinse arms

• Inlet valves

• Drainage components

• Contactors and relays

• Fans on applicable machines

• Other moving or electrically operated components

Some sound is completely normal.

What matters is a sound that is new, louder than normal, intermittent or accompanied by another problem.

Possible causes of unusual noises can include:

• Broken glass or foreign objects

• Pump problems

• Restricted pump impeller

• Blocked filters

• Wash-arm problems

• Loose components

• Drainage restrictions

• Water-supply problems

• Worn mechanical components

• Electrical components

• Cavitation or abnormal water-flow conditions

• Other machine-specific faults

The Sound Is a Clue — Not a Diagnosis.

What Kind of Noise Is Your Glasswasher Making?

The type of sound can help narrow down where to start looking.

Staff commonly describe unusual glasswasher noises as:

Grinding

A harsh mechanical grinding or scraping sound.

Humming

A motor-like hum without the normal movement of water.

Rattling

A loose, vibrating or intermittent mechanical sound.

Buzzing

An electrical or mechanical buzzing sound.

Knocking

Repeated knocking or banging during part of the cycle.

Squealing or High-Pitched Noise

A new high-frequency sound during operation.

Gurgling

Unusual water or drainage sounds.

Loud Water Noise

Water circulation suddenly sounds different or more forceful than normal.

The description doesn't need to be technically perfect.

Tell us what it sounds like and when it happens.

That information can help considerably.

Commercial Glasswasher Making a Grinding Noise

Don't Ignore a New Grinding Sound.

Grinding is one of the noises that deserves prompt investigation.

Depending on where and when it occurs, possible causes may include:

• Broken glass

• Foreign material

• Pump impeller obstruction

• Pump damage or wear

• Wash-arm interference

• Loose mechanical components

• Other moving-component problems

Commercial glasswashers operate in an environment where glass breakage is unavoidable.

A small fragment can sometimes end up somewhere it shouldn't.

If the grinding began shortly after a glass broke inside the machine, tell the technician.

That timeline may be important.

A Small Piece of Glass Can Create a Much Bigger Problem.

Can Broken Glass Get Into a Commercial Glasswasher Pump?

Potentially.

Filters and strainers are designed to prevent debris from freely entering parts of the machine, but broken glass can create small fragments.

If foreign material reaches or obstructs a moving component, symptoms may include:

• Grinding

• Rattling

• Reduced circulation

• Pump jamming

• Poor drainage

• Intermittent operation

Don't reach into concealed pump areas while the machine is connected to power.

If glass has broken:

1. Turn the machine off as appropriate.

2. Follow the manufacturer's safe cleaning procedure.

3. Remove only debris accessible through normal operator-cleaning areas.

4. Don't dismantle electrical or mechanical components unless appropriately trained.

Commercial Glasswasher Making a Humming Noise

A humming noise can sometimes indicate that an electrically powered component is attempting to operate.

For example, a pump may be energised but unable to operate normally.

Possible areas requiring investigation can include:

• Pump motor

• Restricted impeller

• Foreign object

• Mechanical seizure

• Electrical supply

• Motor capacitor on applicable equipment

• Drainage restriction

• Other machine-specific components

The important distinction is:

Can You Hear the Motor but See No Result?

For example:

Humming + no wash circulation

may direct attention towards the wash system.

Humming + water not draining

may direct attention towards the drainage system.

The noise alone doesn't prove which component has failed.

Glasswasher Humming but Not Washing

If the glasswasher fills normally and then hums without producing its usual wash action, possible areas for investigation include:

• Wash pump

• Pump impeller

• Foreign objects

• Electrical components

• Water level

• Wash-system restrictions

• Controls

Look at the wash arms.

If they aren't operating normally at the same time the humming occurs, mention this when booking.

Weak or missing wash circulation?

Troubleshoot Commercial Glasswasher Pump Problems →

Glasswasher Humming but Not Draining

If the humming occurs specifically when the machine should be draining, the drainage system should be investigated.

Possible causes can include:

• Drain pump problem where fitted

• Pump obstruction

• Foreign material

• Blocked filter

• Drain hose restriction

• Waste restriction

• Drain valve problems

• Electrical faults

• Other drainage-system conditions

A humming drain pump doesn't necessarily mean the pump needs replacing.

It may be attempting to move water against a restriction.

Find Out Why the Water Isn't Moving.

Water staying inside the machine?

Troubleshoot Commercial Glasswasher Not Draining →

Commercial Glasswasher Making a Rattling Noise

Rattling can have several possible causes.

Depending on when it occurs, investigation may include:

• Wash arms

• Rinse arms

• Loose components

• Foreign objects

• Broken glass

• Pump components

• Panels

• Racks or glassware

• Plumbing

• Other mechanical components

One simple distinction can help:

Does the Rattle Stop When the Rack Is Removed?

Sometimes what sounds like a machine fault is actually glassware or a rack moving during the wash cycle.

If the sound continues with an empty machine, the source is more likely to be elsewhere.

Glasswasher Wash Arm Making a Noise

Wash arms rotate while water is being circulated through them on many commercial glasswashers.

Unusual noise around the wash chamber may involve:

• Wash arm contacting something

• Incorrectly positioned arm

• Foreign material

• Blocked jets

• Damaged wash arm

• Rack interference

• Glassware positioned incorrectly

• Circulation problem

Before assuming the pump has failed, check accessible wash arms according to the manufacturer's operator instructions.

A poorly positioned item of glassware can sometimes interfere with normal arm movement.

Check the Simple Things Before Replacing Expensive Parts.

Commercial Glasswasher Making a Buzzing Noise

Buzzing can originate from electrical or electromechanical components.

Depending on the machine, possible sources may include:

• Contactor

• Relay

• Solenoid valve

• Pump motor

• Other electrically operated components

Some electrical components naturally produce a small amount of operating noise.

The concern is a new, unusually loud or abnormal buzz, particularly when accompanied by:

• Failure to start

• Intermittent operation

• Burning smell

• Electrical tripping

• Heating problems

• Filling problems

• Pump problems

If there is a burning smell, smoke, overheating or repeated electrical tripping, stop using the machine and follow appropriate safety procedures.

Commercial Glasswasher Making a Knocking or Banging Noise

Knocking sounds may be related to water movement, moving components or something physically contacting the machine.

Possible areas to consider include:

• Water supply

• Plumbing

• Wash arms

• Rinse arms

• Loose components

• Rack movement

• Pump operation

• Valves

• Drainage

If the noise happens only when the machine fills, that is useful information.

If it happens only during washing, that points the investigation somewhere different.

When It Happens Matters as Much as What It Sounds Like.

Glasswasher Making Noise While Filling

If the unusual sound occurs while the machine is taking in water, possible areas for investigation can include:

• Incoming water supply

• Inlet valve

• Water pressure

• Pipework

• Restrictions

• Solenoid operation

• Other filling-system components

Look for other symptoms occurring at the same time:

• Filling slowly

• Not filling

• Overfilling

• Pulsating water flow

• Water hammer or pipe movement

• Error codes

Machine also having trouble filling?

Troubleshoot Commercial Glasswasher Not Filling →

Glasswasher Making Noise During the Wash Cycle

A noise that begins when washing starts may direct attention towards components operating during the wash stage.

Depending on the machine, these can include:

• Wash pump

• Impeller

• Wash arms

• Filters

• Foreign objects

• Mechanical components

• Electrical controls

Also look at the wash result.

Is the machine:

• Cleaning normally?

• Producing weak spray?

• Leaving glasses dirty?

• Failing to rotate the wash arms?

Noise combined with poor washing gives us more diagnostic information than noise alone.

Glasswasher Making Noise During Rinsing

If the machine washes normally but the noise appears during the rinse stage, possible areas for investigation can include:

• Rinse system

• Rinse arms

• Rinse pump where fitted

• Water supply

• Valves

• Booster system

• Scale or restrictions

• Other machine-specific components

If rinse performance has also deteriorated, mention:

• Weak rinse

• Poor glass finish

• Residue

• Streaks

• Temperature problems

Rinse performance changed too?

Troubleshoot Commercial Glasswasher Not Rinsing Properly →

Glasswasher Making Noise While Draining

A noise that occurs specifically at the end of a cycle or while water is being removed can narrow the investigation towards the drainage system.

Possible causes can include:

• Drain pump where fitted

• Pump obstruction

• Broken glass

• Foreign debris

• Drain hose

• Waste restriction

• Drain valve

• Water flow through the waste system

If the noise is accompanied by water remaining inside the tank, drainage diagnosis becomes particularly important.

Glasswasher Making Noise but Still Working

"It Still Works" Doesn't Mean Nothing Is Wrong.

A machine can continue operating while a fault is developing.

For example, a foreign object may initially produce only a rattle.

A pump may become progressively louder before performance deteriorates.

A loose component may vibrate without immediately stopping the machine.

This doesn't mean every new noise requires an expensive repair.

It means a persistent change shouldn't simply be dismissed.

Early Diagnosis Can Be Much Simpler Than Waiting for Complete Failure.

Glasswasher Suddenly Much Louder Than Normal

A sudden increase in operating noise is useful diagnostic information.

Ask:

Did it happen after something changed?

For example:

• A glass broke

• The machine was cleaned

• Filters were removed and refitted

• Wash arms were removed

• The machine was serviced

• Plumbing work was completed

• The machine was moved

• A blockage occurred

• A previous repair was performed

If the timing lines up with another event, tell us.

Changes Leave Clues.

Glasswasher Gradually Getting Louder

A gradual increase in noise can indicate a different pattern from a sudden grinding sound.

Possible causes may involve:

• Mechanical wear

• Pump condition

• Increasing restrictions

• Loose components

• Scale

• Vibration

• Other developing faults

Try to identify whether the sound has changed over:

• Days

• Weeks

• Months

and whether performance has changed at the same time.

Could Scale Make a Glasswasher Noisy?

Scale itself doesn't explain every mechanical noise.

However, mineral accumulation can restrict water pathways and affect the way water moves through parts of the machine.

Scale may also contribute to problems involving:

• Wash jets

• Rinse jets

• Wash arms

• Water flow

• Heating systems

• Valves

If unusual water noise appears alongside visible scale, cloudy glasses or poor rinse performance, water hardness may be relevant to the wider diagnosis.

Scale keeps returning?

Troubleshoot Commercial Glasswasher Water Softener Problems →

Pump Noise Doesn't Automatically Mean the Pump Has Failed

This is particularly important.

If a noise seems to come from the pump, it's easy to conclude:

"We need a new pump."

But abnormal pump noise can also be associated with:

• Foreign material

• Broken glass

• Impeller obstruction

• Restricted water flow

• Incorrect water level

• Drainage restrictions

• Electrical conditions

• Other surrounding components

A pump may need replacement in some cases.

In others, the pump itself may not be the root cause.

Find the Cause. Fix What Matters.

Suspect a pump problem?

Troubleshoot Commercial Glasswasher Pump Problems →

Could Low Water Level Make a Glasswasher Pump Sound Different?

Potentially.

A pump is designed to operate under particular water conditions.

If the machine doesn't contain the expected amount of water, the sound and performance of the circulation system can change.

Possible water-level problems can involve:

• Filling system

• Inlet valve

• Water-level sensor

• Pressure system

• Drainage

• Controls

If unusual pump noise appears alongside a low water level or poor circulation, mention both symptoms.

Is the Noise Actually Coming From the Glasswasher?

Not always.

Commercial kitchens are noisy environments.

A vibration can travel through:

• Stainless benches

• Drain pipes

• Water pipes

• Adjacent equipment

• Wall panels

• Racking

A noise that appears to come from the glasswasher may actually originate from connected plumbing or nearby equipment.

Diagnosis should establish the source before parts are replaced.

Should I Keep Using a Noisy Commercial Glasswasher?

It depends on the nature of the noise and whether other symptoms are present.

A minor new vibration may have a very different level of urgency from:

• Severe grinding

• Electrical buzzing with burning smell

• Smoke

• Repeated electrical tripping

• Water leaking near electrical components

• Pump seizure

• Violent knocking

• Significant mechanical damage

If there is any electrical or workplace safety concern, stop using the equipment and follow appropriate safety procedures.

For persistent abnormal mechanical noise, arranging diagnosis before continuing heavy operation can help prevent a developing problem from becoming more serious.

What Staff Can Check Before Calling for Service

You don't need to dismantle the machine.

A few observations can make diagnosis much easier.

Listen for When It Happens

Does the noise occur during:

• Filling?

• Washing?

• Rinsing?

• Draining?

• Heating?

• The entire cycle?

Describe the Sound

Is it:

• Grinding?

• Humming?

• Rattling?

• Buzzing?

• Knocking?

• Squealing?

• Gurgling?

Check the Glassware and Rack

Is something interfering with the wash arms?

Check Operator-Accessible Filters

Clean and inspect filters according to the manufacturer's operating instructions.

Check Accessible Wash Arms

Make sure they are correctly fitted and able to move as intended.

Think About Broken Glass

Did a glass break shortly before the noise began?

Look for Other Symptoms

Is the machine also:

• Not cleaning?

• Not draining?

• Leaking?

• Filling slowly?

• Rinsing poorly?

• Showing an error code?

Record the Noise

If possible, take a short video with sound.

A recording can be extremely useful if the noise is intermittent.

What Not to Do With a Noisy Glasswasher

Don't:

• Put your hand near moving components

• Reach into concealed pump areas

• Remove electrical panels unless appropriately qualified

• Repeatedly operate a machine making severe grinding noises

• Keep resetting electrical protection that trips

• Assume every pump noise means a new pump

• Ignore broken glass inside the machine

• Randomly replace components based on sound alone

A Noise Tells You Where to Investigate. Testing Tells You What to Repair.

How We Diagnose Unusual Commercial Glasswasher Noises

1. Tell Us What It Sounds Like

You don't need technical terminology.

Tell us:

• What the sound resembles

• When it happens

• How long it has been happening

• Whether it started suddenly

• Whether anything else changed

If possible, send us a video. Click here to send us an enquiry.

2. We Identify Which Stage Produces the Noise

Is it happening during:

Filling?

Washing?

Rinsing?

Draining?

Heating?

That immediately helps narrow the investigation.

3. We Inspect the Relevant System

Depending on the symptoms and equipment, diagnosis may involve relevant:

• Wash pump

• Drain pump

• Rinse pump

• Pump impellers

• Wash arms

• Rinse arms

• Filters

• Foreign objects

• Drainage system

• Inlet system

• Water level

• Valves

• Contactors

• Relays

• Wiring

• Plumbing

• Mechanical components

• Controls

4. We Find the Source

The objective isn't simply to make the sound disappear.

It's to understand why it started.

5. We Explain What's Required

Once the cause has been identified, we can explain the appropriate repair or corrective action.

Find the Cause. Fix What Matters.

Why Correct Diagnosis Matters

Imagine a glasswasher starts grinding during the wash cycle.

Someone assumes:

"The wash pump is failing."

A new pump is ordered.

But when the machine is inspected, a fragment of broken glass is interfering with the system.

Or consider a humming machine that won't drain.

Again, the pump gets blamed.

But the real problem is a restriction in the drainage system.

Different faults can produce similar sounds.

The Most Expensive Assumption Is the One That Replaces the Wrong Part.

That's why Worldwide CDM starts with diagnosis.

Find the Cause. Fix What Matters.

Commercial Glasswasher Noise Problems Across Sydney

Worldwide CDM diagnoses and repairs noisy commercial glasswashers for:

• Restaurants

• Bars

• Pubs

• Clubs

• Hotels

• Cafés

• Function centres

• Catering businesses

• Commercial kitchens

• Hospitality venues

We provide commercial glasswasher servicing and repairs throughout Sydney and surrounding service areas.

Commercial Glasswasher Brands We Repair

Worldwide CDM diagnoses and repairs faults across many commercial glasswasher brands used throughout Sydney hospitality venues, including:

• Lamber

• Eswood

• Washtech

• Sammic

• Norris

• Adler

• Aristarco

• Baron

• Jemi

• Smartwash

Contact us with your glasswasher brand, model and a description of where the water is appearing. Click Here To Submit An Enquiry.

More Than 30 Years of Commercial Equipment Experience

A strange noise doesn't tell you which part to order.

It tells you that something has changed.

Worldwide CDM is a family-run commercial catering equipment business with more than 30 years of experience supporting Sydney hospitality businesses.

Our approach is straightforward:

Listen to the symptom.

Identify when it happens.

Inspect the relevant system.

Find the cause.

Repair what's actually required.

Find the Cause. Fix What Matters.

Keep Serving Customers With Confidence.

Related Commercial Glasswasher Problems

Commercial Glasswasher Pump Problems

Humming, grinding or weak water circulation?

Troubleshoot Commercial Glasswasher Pump Problems →

Commercial Glasswasher Not Draining

Humming or unusual drainage noise with water remaining inside?

Troubleshoot Commercial Glasswasher Not Draining →

Commercial Glasswasher Not Filling

Noise occurring while the machine attempts to fill?

Troubleshoot Commercial Glasswasher Not Filling →

Commercial Glasswasher Not Rinsing Properly

Unusual noise occurring during the rinse stage?

Troubleshoot Commercial Glasswasher Not Rinsing Properly →

Commercial Glasswasher Leaking Water

New noise accompanied by water underneath the machine?

Troubleshoot Commercial Glasswasher Leaking Water →

Commercial Glasswasher Water Softener Problems

Scale, water-flow changes or mineral build-up occurring as well?

Troubleshoot Commercial Glasswasher Water Softener Problems →