What Is Chemical Dosing in a Commercial Glasswasher?

Commercial glasswashing relies on several processes working together.

Water temperature, wash action, rinse performance, water quality and chemical concentration can all influence the final result.

Two chemicals commonly used in the process are:

Detergent

Commercial glasswasher detergent assists the wash process in removing contamination from glassware.

Too little detergent may contribute to poor cleaning.

Too much isn't automatically better and can contribute to residue, unnecessary chemical consumption and poor results if the overall washing and rinsing process isn't correctly balanced.

Rinse Aid

Rinse aid is introduced during the final rinse process and helps water drain from the surface of the glassware more effectively.

Incorrect rinse-aid delivery can contribute to problems such as:

• Water spots

• Streaking

• Poor drying

• Film

• Uneven glass appearance

The objective isn't to maximise chemical use.

It's to achieve the correct chemical concentration for the equipment, product, water and operating conditions.

Signs Your Glasswasher May Have a Chemical Dosing Problem

Chemical dosing problems don't always produce an error code.

Instead, your staff may notice a change in glasswashing performance.

Common warning signs can include:

Glasses Suddenly Coming Out Cloudy

A film or cloudy appearance may involve detergent, rinse aid, water quality, scale or other wash and rinse conditions.

White Spots or Marks

White marks can involve mineral deposits and water hardness, but chemical dosing and rinse performance may also need to be considered.

Streaks Across Glassware

Incorrect rinse-aid concentration can contribute to streaking or an uneven finish.

Glasses Not Drying Properly

If excessive water remains on glassware after the cycle, rinse-aid delivery is one factor that may need investigation.

Poor Cleaning Results

If insufficient detergent is entering the wash process, cleaning performance may deteriorate.

However, poor cleaning doesn't automatically mean the machine simply needs more detergent.

Chemical Container Emptying Too Quickly

A sudden increase in detergent or rinse-aid consumption may indicate excessive dosing, an incorrect setting, a leak or another chemical-delivery problem.

Chemical Container Lasting Much Longer Than Normal

This can be just as important.

If a chemical container that normally requires regular replacement suddenly seems to last much longer while wash quality deteriorates, the chemical may not be entering the machine as expected.

No Visible Chemical Moving Through the Line

Depending on the dosing system and tubing, lack of expected chemical movement may indicate a delivery problem that requires investigation.

Why Has My Commercial Glasswasher Stopped Dosing Chemicals?

A dosing problem can have several possible causes.

Depending on the equipment and chemical system, areas that may need investigation include:

• Empty detergent or rinse-aid containers

• Chemical pickup tubes

• Blocked chemical lines

• Crystallised chemical within tubing

• Split, hardened or damaged tubing

• Air entering a chemical line

• Poor priming

• Dosing pump problems

• Incorrect dosing settings

• Chemical leaks

• Incorrect chemical

• Recent changes in chemical product

• Electrical or control problems

• Water conditions

• Other machine-specific faults

The visible symptom doesn't necessarily identify which one is responsible.

Diagnose the Dosing System Before Continually Adjusting It.

Commercial Glasswasher Dosing Pump Problems

Some commercial glasswashers use dosing pumps to deliver detergent, rinse aid or both.

When the dosing system isn't operating correctly, the machine itself may still appear to run normally.

The wash pump can operate.

The machine can heat.

The rinse cycle can occur.

The cycle can finish.

But the expected amount of chemical may not be reaching the wash or rinse process.

That can make dosing faults easy to overlook.

Depending on the system, diagnosis may involve checking the relevant:

• Dosing pump

• Chemical tubing

• Pickup lines

• Connections

• Priming

• Chemical supply

• Dosing settings

• Electrical supply

• Controls

Simply increasing a dosing setting won't fix a chemical pump or delivery system that isn't operating correctly.

Commercial Glasswasher Detergent Dosing Problems

Too Little Detergent

If insufficient detergent is being delivered, wash performance may deteriorate.

Staff might notice:

• Lipstick remaining on glass rims

• Drink residue

• Greasy film

• Fingerprints

• Poor overall cleaning

• Increasing numbers of glasses requiring rewashing

But detergent is only one part of the washing process.

Poor cleaning can also involve temperature, wash pressure, blocked jets, dirty filters, wash-water condition, loading or other equipment problems.

That's why poor cleaning should not automatically lead to the detergent setting being increased.

Can Too Much Detergent Cause Problems?

Yes.

More detergent doesn't necessarily mean better cleaning.

Excessive detergent can increase chemical consumption and may contribute to residue or poor finishing when the overall wash and rinse process isn't correctly balanced.

If staff continually increase detergent because glasses aren't coming out clean, they may be compensating for an entirely different fault.

For example, the underlying problem could involve:

• Wash performance

• Water temperature

• Rinse performance

• Blocked jets

• Water conditions

• Scale

• Loading

• Another mechanical or operating issue

Fix the Cause Instead of Compensating With More Chemical.

Commercial Glasswasher Rinse Aid Problems

Rinse aid helps water drain from glass surfaces during the final stages of glasswashing.

Incorrect rinse-aid dosing may contribute to:

• Water spots

• Streaks

• Film

• Poor drying

• Uneven finish

• Excessive droplets remaining on glassware

However, these symptoms don't automatically prove the rinse-aid system is responsible.

Rinse performance, water pressure, rinse temperature, water hardness and scale can produce similar symptoms.

That's why the whole process needs to be considered.

Can Too Much Rinse Aid Cause Problems?

Yes.

If glassware isn't drying properly or has visible marks, repeatedly increasing the rinse aid isn't necessarily the answer.

Both insufficient and excessive dosing can affect the finished result.

The appropriate concentration depends on factors including the chemical product, machine, water conditions and operating requirements.

If a machine previously produced clear glassware and the problem suddenly developed, identifying what changed is often more useful than immediately changing the dosing setting.

Did the Problem Start After Changing Chemicals?

Tell Us.

This is an important diagnostic clue.

Different detergent and rinse-aid products can have different formulations, concentrations and recommended dosing requirements.

A dosing arrangement suitable for one product may not necessarily be appropriate for another.

If glasswashing performance changed shortly after:

• Changing detergent

• Changing rinse aid

• Changing chemical supplier

• Replacing a chemical container

• Adjusting dosing settings

• Servicing the dosing system

tell the technician.

The timing may help narrow down the cause.

Blocked Glasswasher Chemical Dosing Lines

Chemical delivery depends on the chemical being able to travel from its container through the dosing system.

Depending on the system and circumstances, chemical lines can become restricted.

Problems may include:

• Chemical deposits

• Crystallisation

• Kinked tubing

• Damaged tubing

• Blocked pickup points

• Air entering the line

• Incorrect installation or connection

A blocked line can mean the dosing pump is operating without the expected amount of chemical reaching the machine.

This is another reason simply changing the dosing setting may not solve the problem.

Damaged Glasswasher Chemical Tubing

Chemical tubing doesn't last forever.

Tubing can deteriorate with age, chemical exposure, heat, movement and normal use.

Depending on the type of system, damaged tubing may lead to:

• Poor chemical delivery

• Inconsistent dosing

• Air entering the system

• Chemical leakage

• Loss of prime

• Increased or reduced chemical consumption

Chemical leaks should be dealt with carefully because commercial cleaning chemicals can be hazardous.

Avoid direct contact and follow the chemical supplier's safety instructions.

Why Does My Glasswasher Keep Losing Prime?

If chemical isn't being drawn through the dosing system correctly, the line may fail to remain primed.

Possible causes can include:

• Empty chemical container

• Pickup tube problems

• Air leaks

• Damaged tubing

• Loose connections

• Dosing pump problems

• Blockages

• Other system-specific issues

Repeatedly priming a system without identifying why it keeps losing prime may only temporarily mask the problem.

My Glasswasher Is Using Too Much Detergent or Rinse Aid

Unexpectedly high chemical consumption costs money.

If detergent or rinse aid is disappearing much faster than usual, don't assume that's simply what the machine requires.

Possible factors may include:

• Excessive dosing

• Incorrect settings

• Leakage

• Chemical delivery problems

• Incorrect setup

• Changes to the chemical product

• Changes in operating conditions

Chemical usage should be considered alongside the quality of the finished glassware.

If chemical consumption has increased while results have become worse, that is particularly worth investigating.

My Glasswasher Isn't Using Any Detergent or Rinse Aid

The opposite problem can occur.

If a chemical container barely changes over time and glasswashing performance has deteriorated, check whether the chemical is actually being delivered.

Depending on the equipment, possible causes may involve:

• Dosing pump operation

• Blocked lines

• Pickup tubes

• Damaged tubing

• Priming

• Settings

• Controls

• Chemical supply

A machine can complete a normal-looking cycle even when the chemical dosing process isn't operating as intended.

Chemical Dosing or Hard Water?

They Can Look Like the Same Problem.

This is where glasswasher diagnosis becomes more complicated.

Cloudiness, white marks and poor glass appearance aren't always caused by chemicals.

Hard water contains dissolved minerals that can leave deposits as water evaporates.

Hard-water conditions can also contribute to scale accumulation inside the glasswasher.

That means repeatedly changing detergent or rinse-aid settings may not solve the problem if the underlying issue is water quality or water treatment.

Where relevant, the following may need consideration:

• Water hardness

• Water softener operation

• Salt levels

• Water treatment

• Scale accumulation

• Chemical suitability for the water conditions

Don't Try to Fix a Water Problem With More Chemical.

Chemical Dosing or Poor Rinsing?

Another common diagnostic mistake is assuming visible chemical residue automatically means too much detergent.

The actual problem could be that the detergent isn't being rinsed away effectively.

Poor rinsing can involve:

• Restricted rinse jets

• Blocked rinse arms

• Water-pressure problems

• Water-supply restrictions

• Rinse valve faults

• Rinse pump problems

• Temperature problems

• Scale

• Other rinse-system faults

This is why we look at the entire glasswashing process rather than one setting in isolation.

Having rinse problems too?

Troubleshoot Commercial Glasswasher Not Rinsing Properly →

Chemical Dosing or a Cleaning Problem?

If glasses are coming out dirty, chemical concentration is only one possible cause.

The wash system itself may need attention.

Problems can involve:

• Wash jets

• Wash arms

• Filters

• Wash pump

• Temperature

• Water level

• Wash-water condition

• Loading

• Scale

• Chemical dosing

Glasses still coming out dirty?

Troubleshoot Commercial Glasswasher Not Cleaning Properly →

Chemical Dosing and Cloudy Glasses

Cloudiness deserves its own diagnosis because several very different problems can look similar.

Possible causes include:

• Detergent concentration

• Rinse-aid concentration

• Hard water

• Mineral deposits

• Scale

• Poor rinsing

• Water treatment

• Glassware deterioration

• Permanent glass etching

A removable film and permanent damage to the glass surface aren't the same thing.

Before continually adjusting chemicals, determine what you're actually seeing.

Seeing cloudy glassware?

Troubleshoot Commercial Glasswasher Leaving Glasses Cloudy →

What Staff Can Check Before Calling for Service

Before booking a technician, there are several basic observations that may help.

Check the Chemical Containers

Are the detergent and rinse-aid containers empty?

Check the Pickup Tubes

Are they actually sitting in the correct chemical container?

Look for Obvious Tubing Problems

Without dismantling the machine, look for visible disconnected, kinked or damaged external chemical lines.

Think About What Recently Changed

Did the problem begin after changing chemicals, replacing a container or adjusting the machine?

Look at the Glassware

Is it:

• Dirty?

• Cloudy?

• Streaked?

• Spotted?

• Wet?

• Covered in residue?

Different symptoms provide different clues.

Check Whether Every Rack Is Affected

Consistent problems across every rack can point in a different direction from poor results affecting only certain rack positions.

Don't Randomly Adjust Internal Settings.

If you don't know the correct dosing requirements, repeatedly changing settings can make the original problem harder to diagnose.

How We Diagnose Commercial Glasswasher Dosing Problems

1. Tell Us What Changed

Tell us what the glassware looks like, whether chemical consumption has changed and whether anything happened shortly before the problem began.

Click here to provide us with the details.

2. We Assess the Relevant Systems

Depending on the symptoms and machine, this may include the relevant:

• Chemical supply

• Dosing pumps

• Chemical lines

• Tubing

• Pickup system

• Priming

• Dosing settings

• Wash performance

• Rinse performance

• Water conditions

• Heating

• Controls

3. We Identify the Actual Cause

A dosing problem shouldn't automatically become a dosing-pump replacement.

The problem may be a blocked line.

It may be damaged tubing.

It may be an incorrect setting.

It may be the chemical itself.

Or chemical dosing may not be the primary problem at all.

4. We Explain What We've Found

We'll explain what's causing the problem and what needs attention.

5. We Repair What's Required

If a glasswasher component requires repair or replacement, we'll recommend the appropriate action.

If the problem is related to chemicals, water treatment or operating conditions rather than a failed machine component, we'll tell you that too.

We Find the Fault Before We Sell the Fix.

Why Correct Diagnosis Matters

Imagine glasses suddenly start coming out streaky.

The immediate reaction might be:

"Turn the rinse aid up."

But what if the actual problem is poor rinse pressure?

Or a dosing line?

Or the chemical was recently changed?

Or the water conditions are contributing to the marks?

Increasing one setting can change the symptom without addressing the cause.

That's why our approach is based on diagnosis rather than trial and error.

Test. Diagnose. Then Repair or Adjust What Actually Requires Attention.

Commercial Glasswasher Dosing Problems Across Sydney

Worldwide CDM diagnoses and repairs commercial glasswasher performance and chemical dosing problems for:

• Restaurants

• Bars

• Pubs

• Clubs

• Hotels

• Cafés

• Function centres

• Catering businesses

• Commercial kitchens

• Hospitality venues

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

More Than 30 Years of Commercial Equipment Experience

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

We understand how disruptive poor glasswashing performance can become during service.

Staff shouldn't have to keep rewashing racks, polishing glasses or experimenting with chemical settings while clean glassware runs short.

Our approach is straightforward:

Understand the symptom.

Assess the system.

Identify the cause.

Explain what's wrong.

Repair what actually requires attention.

We Find the Fault Before We Sell the Fix.