The dishwasher finishes its cycle. The clean rack cannot move because the landing bench is full. Meanwhile, someone carries dirty plates across the same space to reach the pre-rinse. Buying a faster machine will not fix that junction.
A pass-through dishwasher is a station, not a stainless-steel box. The buying decision is whether dirty ware, loaded racks, clean ware and people can keep moving through it. A straight line often makes that route easy to read. A corner can make better use of a difficult room. Both can fail if the drawing ends at the machine’s outlet.
This guide compares two hypothetical proposals using the same incoming work. Use the rack-flow calculation, then take the printable survey to your own busiest service.
Draw the rack’s complete journey
Start at the dirty return, not at the machine. Follow a plate through sorting and scraping, any preparation required by the operating procedure, loading, washing, clean landing and unloading. Then trace the empty rack back. Mark storage and waste removal too: those movements still happen when the drawing looks tidy.
Scroll the diagram sideways to read every label.
On the plan, colour dirty handling one colour and clean handling another. Where the colours cross, write what actually happens there. “Clean rack waits while trolley passes” is a more useful note than “tight area”. A rack that must be lifted off its table to get around a corner deserves its own mark.
Corner capability is model-specific. Winterhalter’s PT Series information describes straight and corner configurations and alternative working directions. That establishes an available design option, not permission to rotate any dishwasher beside any bench. Obtain the exact Australian model drawing and compatible tabling proposal before ordering.
A worked example: the machine fits, but does the station work?
Hypothetical planning example—not a machine rating or a customer trial. A restaurant wants to process 12 loaded racks arriving over 20 minutes. For this simplified comparison they arrive evenly: one every 100 seconds. The proposed operating programme and changeover are assumed to occupy the machine position for 90 seconds per rack. Those figures must be replaced with an observed arrival trace and a supplier-validated operating trial.
Both layouts provide two usable clean-rack positions. For arithmetic only, each rack occupies a measured 500 × 500 mm square. Thus two rack squares need 1,000 mm along a straight landing edge. That excludes table lips, gaps, machine connections, support details and working space; it is not a fabrication dimension.
| Planning input | Straight proposal | Corner proposal |
|---|---|---|
| Incoming work | 12 racks / 20 minutes | 12 racks / 20 minutes |
| Machine position occupied | 90 seconds per rack | 90 seconds per rack |
| Clean positions | 2 | 2 |
| Clean rack removed to storage | One every 80 seconds | One every 120 seconds |
| Reason for assumed difference | Storage is on the clean-side route | Operator waits at a shared trolley crossing |
Scroll the table sideways to see every column.
The clean-removal intervals are deliberately different assumptions to expose a bottleneck. They are not inherent speeds of straight and corner layouts. A different room could reverse them.
First, separate three rates
Demand is 12 ÷ 20 = 0.6 racks a minute, or 36 racks an hour expressed as an equivalent rate. The assumed machine interval allows 60 ÷ 90 = 0.667 racks a minute, equivalent to 40 an hour. That small arithmetic margin says nothing about wash quality, recovery, interruptions or staff availability.
The straight proposal clears clean racks at 60 ÷ 80 = 0.75 a minute. The corner proposal clears them at 60 ÷ 120 = 0.5 a minute. Under these assumptions, the corner’s clean exit is slower than incoming demand, even though the machine position is fast enough on paper.
Then locate the blockage
Assume the first rack enters at time zero, completes at 1:30, and every subsequent rack enters 100 seconds after the previous one. A clean rack occupies a landing position from completion until its removal finishes. Clean removal begins as soon as a rack is available and proceeds continuously at the stated interval.
| Event | Time from start | What it reveals |
|---|---|---|
| Rack 1 completes | 1:30 | Clean removal starts; finishes 3:30 |
| Rack 2 completes | 3:10 | Both landing positions occupied until 3:30 |
| Rack 6 completes | 9:50 | Rack 5 is being removed until 11:30; rack 6 waits |
| Rack 7 completes | 11:30 | Removal of rack 5 frees a position at that instant |
| Rack 8 completes | 13:10 | Racks 6 and 7 occupy both positions until 13:30: outlet blocks for 20 seconds |
Scroll the table sideways to see every column.
This trace assumes an immediate transfer when a position opens and ignores knock-on delays after the first blockage. It is a screening calculation, not a complete simulation. Real arrivals bunch, removal stops, and some loads need extra handling. Record those events rather than smoothing them into an attractive hourly average.
The useful change is to test a different clean exit. Move storage or the trolley route, then time clean removal again. Adding a third landing position could absorb a short pulse but does not cure a sustained 0.6-in/0.5-out imbalance. Buying a faster machine would feed the blocked exit sooner.
Which arrangement deserves the next drawing?
| What your survey shows | Better next step | What could overturn it |
|---|---|---|
| Dirty arrival and clean storage lie on opposite ends of one usable run | Develop the straight proposal first | Door swings or service access interrupt that run |
| Room geometry prevents a continuous run; adjacent walls offer a clean exit | Develop a manufacturer-supported corner proposal | The turn puts clean unloading into the dirty return |
| Both fit, but only one avoids repeated lifting or a shared crossing | Mock up that route with actual racks | Staff cannot reach controls or unload comfortably |
| Clean landing stays full in both | Resolve unloading and storage first | A measured trial identifies a different bottleneck |
| The model cannot support the proposed connection or working direction | Change the machine/tabling package | Written manufacturer confirmation supplies an approved alternative |
Scroll the table sideways to see every column.
Use tape or cardboard to mark the complete station before fixed tabling is fabricated. Walk it with the people who will operate it. Include a returning trolley and an open neighbouring door. This exercise exposes conflicts; it does not establish compliant access widths, installation clearances or ergonomic suitability.
Take this survey to one busy service
Count actual loaded racks, including rewashes and separate load types. Record each arrival time and clean-removal completion, rather than converting covers into an assumed racks-per-hour figure. Note who is available to sort, load and unload; one person’s time cannot be allocated to simultaneous tasks twice.
- Measure: room edges, rack dimensions, usable table areas, door swings and nearby routes.
- Watch: record the busiest 20 minutes and the largest short arrival pulse within it.
- Trace: follow dirty ware, clean ware, empty racks and waste separately.
- Test: compare both proposals using the same observed arrivals and staffing.
- Confirm: obtain the exact installation drawing, tabling connections and services schedule.
For your own supplier brief, record station measurements, task route, supported configuration, actual observations and supplier confirmations. Replace the fictional inputs with actual evidence and leave unresolved decisions visible.
Ask for a station quote, not a machine price
Give the supplier both marked-up layouts, rack dimensions, the arrival record, intended loads and site photographs. Ask for the nominated Australian model, compatible inlet/outlet tables, any corner components, working direction, rack guides and usable landing areas on one drawing.
The installation scope should identify electrical supply, water conditions and treatment, drainage, dosing, ventilation or steam-management requirements, commissioning and service access against that exact model. Do not import clearances from an overseas manual or assume an existing connection is suitable.
“Please demonstrate this station against our rack arrival trace, including clean unloading. Identify where racks wait, who handles them, and which installation and tabling assumptions remain unconfirmed.”
Browse Atlantic’s pass-through dishwashers with that brief beside you. The right proposal is the one that explains the complete route and its limits.
Sources and assumptions
Winterhalter PT Series manufacturer information, accessed 18 October 2026, describes straight/corner configurations, working directions and matched inlet tables/drain tops. This is configuration evidence, not a local installation specification. All demand, timing and rack-space figures in the comparison are hypothetical inputs. Obtain current Australian documentation for the exact quoted model.
About this guide
Prepared by Atlantic Equipment. This guide turns a pass-through dishwasher layout into a testable rack-flow brief. Its worked comparison separates incoming demand, machine occupation and clean-side removal so an apparent capacity problem can be investigated before equipment is ordered. The example is hypothetical; it reports no customer trial and specifies no universal installation dimensions.
