How a commercial dishwasher works
A commercial dishwasher cleans a rack in one to three minutes. It can do that because it relies on chemicals and heat far more than scrubbing, so detergent, temperature and clean rinse jets all have to be right.
Watch: Robbo and Kiri on dishwasher basics
Short cycles, so chemicals do the heavy lifting
In Kitchen Talk Episode 3, Robbo and Kiri get back to basics. Washing by hand is mostly mechanical action: scrubbing with a brush. A commercial dishwasher flips that around. A wash cycle is short, around one, two or three minutes, so there's little time for mechanical action and the machine relies on good chemicals. A quality detergent is essential.
Detergent concentration and titration
Concentration is critical too. If the detergent is too weak, it won't clean. When we service a machine, we test the concentration with a simple test called a titration, which tells us whether the dosing is right.
A good wash comes down to four factors: time, temperature, chemical action and mechanical action. If one drops off, the others have to work harder.
Temperature matters
If the wash water isn't hot enough, the detergent doesn't work well. If it's too hot, proteins like egg bake onto the dishes. The reference standard, DIN 10512, puts the wash tank at 60–65°C.
A cycle runs through prewash, wash, rinse and dry. The final rinse needs enough temperature and time to sanitise: 80–85°C under DIN 10512. Machines that sanitise with chemicals instead run at the manufacturer's temperatures.
Clean jets and a working rinse pump
Rinse temperature only helps if the rinse jets are clean and the water pressure or rinse pump is working properly. Blocked jets mean dishes that aren't properly rinsed or sanitised.
Good water treatment, such as reverse osmosis or BWT filters, helps keep scale off the elements and jets and gives a better finish.
What we check on every service
- Detergent concentration, tested by titration
- Wash and final rinse temperatures
- Wash and rinse jets
- Water pressure and the rinse pump
- Sanitation testing, helping you meet health and safety requirements
- An electronic service report when the job's done, so you have a clear record of the work
See our dishwasher hygiene check and planned maintenance for more. CES Wellington offers 7-day cover with after-hours emergency cover.
Need your commercial dishwasher checked?
Call 0800 90 60 30, email service@cesw.co.nz or book a job. 7-day cover with after-hours emergency cover.