Short answer: A softener prevents or reduces hardness scale; it does not fix every white mark. Cloudiness can be residue, incorrect dosing, poor rinsing, high dissolved solids or permanent glass corrosion.
Clouding continues after a softener is fitted. The common misconception is that all white marks are limescale caused by hard water. This article turns that assumption into specific checks that can be recorded on the drawing, survey or commissioning sheet.
Model-specific rule: Chemical dosing changes must follow the machine and chemical supplier instructions. Where gas, electricity, refrigeration, guarded components, hot oil, pressure or safety controls are involved, use the appropriately competent engineer and never bypass a safety device.
First decide whether the mark is removable
Mineral or chemical residue may wipe or dissolve; etching is permanent surface damage. Replacing treatment settings will not restore etched glass.
- Compare wet and dry appearance.
- Test an affected glass away from service.
- Separate residue from permanent damage.
Test treated water rather than assuming
An exhausted, bypassed or incorrectly regenerated softener may deliver hard water. Conversely, soft water with high total dissolved solids can still leave marks.
- Measure raw and treated hardness.
- Check salt/regeneration and bypass position.
- Record conductivity or TDS where relevant.
Dosing and temperature complete the process
Too much or too little detergent/rinse aid, incorrect final rinse and blocked jets affect drainage from the glass. Change one verified variable at a time.
- Check chemical product and dosing rate.
- Verify wash/final-rinse conditions.
- Inspect user-cleanable jets and filters.
What the site evidence may show
| Observation | Hidden issue | Next check |
|---|---|---|
| White film wipes off | Residue/dosing likely | Test water and chemical settings |
| Mark never removes | Glass may be etched | Confirm with supplier; replace glass |
| Softener is present | Treated hardness is still high | Check regeneration/bypass |
A practical verification sequence
- Confirm the exact duty and model. Record what the appliance or space must achieve at peak service and use the current model-specific installation information.
- Draw the complete interface. Include moving parts, service/removal access, connections, adjacent equipment and the real operator or trolley position.
- Measure under a representative condition. Static, empty or isolated tests can hide the issue. Record the operating state, value, unit and test point.
- Correct and prove. Repeat the same test after any change and retain the evidence with commissioning or O&M information.
Checks to record:
- Raw/treated hardness.
- TDS/conductivity.
- detergent/rinse dosing.
- rinse temperature.
- glass condition.
- drying result..
Separate temporary residue from permanent etching and check hardness, TDS, detergent, rinse aid, temperature, dosing and glasswasher setup in a defined order. The result should be a measurable decision rather than a generic note such as “allow sufficient space” or “services by others”.
Common mistakes to avoid
- Calling every white mark limescale.
- Changing several chemical settings together.
- Assuming salt in the softener proves treatment.
- Lowering or raising temperatures without the manual.
Frequently asked questions
Can soft water still leave spots?
Yes. Dissolved solids, rinse performance, dosing and drying can still create deposits.
Will polishing remove etching?
Permanent glass corrosion is not a normal removable wash deposit; affected glass usually needs replacement.
What should be checked first?
Determine whether the mark is removable, then test raw/treated water and verify chemical and rinse settings.
Related Kitchen Install Guide reading
- How Incorrect Drainage Causes Dishwasher Faults
- Commercial Dishwasher Not Cleaning Properly
- Dishwasher Wash Temperature vs Rinse Temperature
Record the installation detail before handover
Use the KIG 318 Commercial Kitchen Installation Checklist to record equipment interfaces, measured conditions, outstanding actions and acceptance evidence.
Sources and further guidance
- Winterhalter: PT Series passthrough dishwasher
- MEIKO: DV 120.2 installation and service manual
- Water Regs UK: Backflow protection
Last reviewed: 14 August 2026. This article provides general commercial-kitchen design and installation information. It does not replace the exact manufacturer instructions, a site-specific design, risk assessment or work by competent specialists. Stop use and obtain competent help where equipment or services may be unsafe.