Choosing the right dishwasher for a restaurant is a much bigger decision than simply finding a machine that can wash plates. A restaurant dishwasher must handle the volume of dishes generated during peak service, clean heavily soiled items, provide an appropriate sanitizing process, fit within the kitchen, work with the available water and electrical supply, and operate reliably day after day. Commercial dishwashers are specifically designed for establishments such as restaurants, bars, cafeterias, hospitals, schools, and other food-service operations where large quantities of dishes, glassware, and utensils must be processed quickly.
The right dishwasher can improve kitchen workflow, reduce labour requirements, control water and energy consumption, and help maintain consistent sanitation. The wrong machine can create bottlenecks, increase utility costs, require excessive manual washing, and potentially create compliance problems if it does not satisfy the requirements applicable to the restaurant. Commercial dishwashers are evaluated according to different machine categories and sanitation approaches, and efficiency criteria vary according to whether a machine is an undercounter, door-type, pot-and-pan, conveyor, or flight-type model.
This guide explains how to choose a restaurant dishwasher from the ground up. It covers dishwasher types, capacity, cycle time, sanitation, high-temperature versus chemical sanitizing, water and energy consumption, installation, detergent and rinse-aid systems, maintenance, restaurant size, kitchen layout, UK considerations, U.S. considerations, Canadian considerations, and the questions you should ask before purchasing.
Why Choosing the Right Restaurant Dishwasher Matters
Dishwashing is one of the most important support operations in a restaurant. Plates, glasses, cups, cutlery, cookware, trays, and utensils continuously move from the dining room or preparation area back into the kitchen. If the dishwasher cannot process these items quickly enough, the entire restaurant can experience a bottleneck. Commercial dishwashers are designed specifically to clean and sanitize large quantities of kitchenware in relatively short periods, making machine capacity an important part of restaurant planning.
A dishwasher should therefore be selected according to the restaurant’s peak workload, not simply its average daily workload. A restaurant might be relatively quiet for several hours but experience a large concentration of dirty dishes during lunch or dinner service. Choosing equipment based on the daily average can result in insufficient capacity precisely when the restaurant needs it most. Commercial equipment guidance emphasizes determining equipment requirements according to service volume, making customer volume and peak demand important factors when selecting commercial dishwashing equipment.
The dishwasher also affects operating costs. Restaurants consume substantial amounts of energy, and commercial dishwashers use energy to heat water, operate pumps, and maintain required operating temperatures. Efficient commercial models can reduce water and energy consumption compared with standard equipment, so the purchase decision should consider lifetime utility costs rather than only the initial equipment price.
Step 1: Determine How Many Dishes Your Restaurant Needs to Wash
The first question should be:
How many dishes, glasses, and utensils need to be washed during the busiest period?
Do not begin by choosing a dishwasher brand or looking at features. Start with the workload.
For example, a small café serving 50 customers during a busy period may have completely different dishwashing requirements from a large restaurant serving 300 customers. A restaurant serving breakfast, lunch, and dinner may also have different requirements from a bar that primarily washes glasses. Commercial dishwasher sizing is linked to the volume of service because the number of people served is a key determinant of the machine type and capacity needed.
Make a practical estimate that includes:
- Plates
- Bowls
- Side plates
- Cups
- Glasses
- Cutlery
- Serving dishes
- Cooking utensils
- Trays
- Pots and pans
- Food-preparation equipment
Then identify how much of this equipment returns to the dishwashing area during your busiest 30- to 60-minute period.
That number is more useful than simply knowing how many customers the restaurant serves each day.
Calculate Your Peak Dishwashing Demand
Suppose a restaurant serves 150 customers during its busiest hour. Each customer generates several washable items, including a dinner plate, side plate, glass, and pieces of cutlery. Additional dishes may be used for appetizers, desserts, sauces, beverages, or shared food.
The actual number of items can therefore be several times the number of customers.
The dishwasher must be capable of processing this workload while allowing for loading, unloading, pre-rinsing or scraping, rack changes, and inevitable interruptions. Commercial machines are designed around rack-based or continuous throughput, which is why commercial specifications often express water consumption in gallons per rack, gallons per square foot of rack, or gallons per hour depending on machine type.
Never select a machine solely because its advertised cycle time appears fast. The restaurant needs to know how many racks it can realistically process during the busiest period.
Understand the Main Types of Commercial Restaurant Dishwashers
There are several major categories of commercial dishwashers.
The most important are:
- Undercounter dishwashers
- Door-type or hood-type dishwashers
- Conveyor dishwashers
- Flight-type dishwashers
- Pot, pan, and utensil washers
- Commercial glasswashers
Commercial efficiency standards specifically distinguish among these categories because their operating characteristics, capacity, water consumption, and energy requirements differ substantially.
Choosing the correct category is often more important than choosing between individual models within the same category.
Undercounter Dishwasher
An undercounter commercial dishwasher is generally one of the most practical choices for a small restaurant, café, bar, or other operation with limited dish volume and limited kitchen space.
The machine is typically installed beneath or near a work surface and uses racks that are loaded manually.
Its major advantages include:
- Compact footprint
- Relatively simple workflow
- Lower initial investment than large conveyor systems
- Suitable for smaller operations
- Easy access
- Less floor space required
Commercial efficiency criteria separately recognize undercounter dishwashers and establish specific water and idle-energy limits for this machine category.
An undercounter machine can be an excellent choice when the restaurant needs commercial equipment but does not have enough dish volume to justify a larger hood-type or conveyor machine.
Door-Type or Hood-Type Dishwasher
A door-type dishwasher, sometimes called a hood-type machine, is designed for higher throughput than an undercounter machine.
A rack of dishes is positioned in the machine, and a hood or door closes over the rack during the wash and rinse process.
These machines can work particularly well in restaurants with moderate to high dish volumes.
One major advantage is workflow. Dirty racks can be placed into the machine, washed, sanitized, and removed without requiring staff to wait for a long domestic-style cycle.
Professional hood-type equipment can have very short cycles, although actual cycle times vary by model, program, sanitation method, and operating conditions.
Conveyor Dishwasher
A conveyor dishwasher is designed for higher-volume operations.
Instead of individually loading and unloading a stationary rack in the same way as a small machine, racks or ware move through a continuous washing system.
Commercial efficiency criteria distinguish single-tank and multiple-tank conveyor systems and measure their water and energy performance according to their specific configuration.
Conveyor systems can be appropriate for:
- Large restaurants
- Hotels
- Banquet facilities
- Institutional kitchens
- Large cafeterias
- High-volume food-service operations
However, they require more space and generally involve a greater installation and capital investment.
Flight-Type Dishwasher
Flight-type systems are designed for very high-volume operations.
Instead of relying exclusively on individual racks, dishes are placed on a moving conveyor or flight system and pass through multiple stages.
These systems can be appropriate for very large restaurants, hotels, hospitals, institutions, and other facilities processing extremely high volumes of ware.
Commercial efficiency requirements treat flight-type machines separately and evaluate their water use according to conveyor characteristics and throughput.
For most small and medium-sized restaurants, a flight-type machine will be unnecessary.
Pot, Pan, and Utensil Dishwasher
If your restaurant frequently washes large pots, pans, trays, mixing bowls, cooking utensils, and other heavy kitchen equipment, a normal plate dishwasher may not be enough.
Commercial standards recognize pot, pan, and utensil machines as a separate category because their design and washing requirements differ from conventional warewashing machines.
A restaurant with a large production kitchen should consider whether cookware requires its own washing solution.
Trying to force large commercial cookware into a standard dishwashing machine can reduce capacity and interfere with proper spray coverage.
Commercial Glasswasher
Bars, pubs, cocktail restaurants, cafés, and restaurants with high beverage sales may have a different requirement: glass turnover.
A glasswasher is designed specifically around glassware and can be particularly useful when large numbers of glasses need to be cleaned quickly.
If a restaurant is constantly running out of clean glasses during busy service, the problem may not be insufficient plate-washing capacity. It may be that the glasswashing process itself needs dedicated equipment.
Step 2: Choose Between High-Temperature and Chemical Sanitizing
One of the most important dishwasher decisions is the sanitation method.
Commercial machines can use high-temperature sanitizing or chemical sanitizing systems. Efficiency standards recognize these as separate approaches, with different water and energy requirements.
A high-temperature dishwasher uses hot water during the final rinse to achieve the required sanitizing conditions.
A chemical-sanitizing dishwasher uses an approved chemical sanitizing solution at the specified concentration and operating conditions.
Neither method should be selected casually. The restaurant needs to consider local regulations, equipment certification, incoming water temperature, installation requirements, chemical handling, operating procedures, and staff training.
High-Temperature Dishwasher
A high-temperature dishwasher uses heat as part of the sanitizing process.
One major advantage is that the machine does not depend on a chemical sanitizer for the final sanitizing step.
However, the machine must be capable of achieving the required temperature at the appropriate stage of the cycle.
In Canada, for example, Ontario’s food-premises regulation specifies requirements for mechanical dishwasher wash temperatures and sanitizing rinse temperatures, while recognizing an exception for machines carrying appropriate commercial certification. The regulation specifies a sanitizing rinse of at least 82°C for the water-based route under the stated conditions.
This illustrates why temperature capability should be considered together with local regulations rather than simply choosing the machine advertised as having the hottest water.
Chemical-Sanitizing Dishwasher
A chemical-sanitizing machine uses a sanitizer rather than relying entirely on very high rinse temperatures.
This approach can reduce the heating demand associated with a high-temperature system, but it introduces another operational responsibility: maintaining the sanitizer at the correct concentration and using the correct chemical.
Chemical sanitizers must be approved or otherwise permitted for the intended use and must be used according to their instructions and applicable regulations. Ontario’s food-premises requirements, for example, address approved sanitizing agents and require access to test reagents for determining sanitizer concentration where chemical sanitizing occurs.
A restaurant choosing chemical sanitizing should therefore have a clear procedure for chemical storage, dosing, concentration testing, staff training, and troubleshooting.
Which Is Better: High Temperature or Chemical Sanitizing?
There is no universal winner.
High-temperature machines can be attractive when the restaurant wants thermal sanitizing and can provide the necessary water and heating infrastructure.
Chemical-sanitizing machines can be attractive when energy requirements, incoming water temperature, or installation conditions make high-temperature operation less convenient.
The final decision should be based on:
- Local health regulations
- Certification
- Water supply
- Available electrical capacity
- Energy costs
- Chemical costs
- Staff procedures
- Maintenance
- Kitchen layout
In the UK, for example, local food-safety guidance commonly emphasizes achieving appropriate time-and-temperature conditions and keeping commercial dishwashers properly maintained. One current local-authority guidance page recommends commercial dishwasher temperatures above 81°C for effective disinfection and recommends monitoring temperatures.
Step 3: Check Dishwasher Certification
Certification is one of the most important things to verify before buying commercial restaurant equipment.
A restaurant should not simply ask whether a dishwasher “sanitizes.”
It should ask:
What commercial standard has the machine been tested or certified against?
Commercial warewashing equipment is covered by dedicated standards that address cleaning and sanitation performance. Current UK commercial-equipment performance requirements reference standards including BS EN IEC 63136 and hygiene requirements under BS EN 17735, while also recognizing relevant commercial warewashing standards for certain equipment.
In North America, commercial certification is also important. Ontario, for example, specifically references certification for commercial use as part of its mechanical-dishwasher provisions.
Always confirm that the exact model not merely the manufacturer or product family is certified for the intended application.
Step 4: Check Cycle Time
Cycle time is one of the most important specifications for a restaurant dishwasher.
A home dishwasher may take a long time because it is designed to run relatively infrequently.
A restaurant dishwasher has a completely different job.
During service, the restaurant may need to:
- Load a rack
- Wash it
- Sanitize it
- Remove it
- Reload
- Repeat
The faster this process can be completed while still achieving the required cleaning and sanitation performance, the greater the potential throughput.
Commercial equipment is specifically designed around short repeated cycles, and some professional machines can complete cycles in only a few minutes or less depending on the configuration.
However, never judge a dishwasher solely by the shortest advertised cycle. Check which program achieves the required sanitation performance and what the real-world throughput is under restaurant operating conditions.
Step 5: Consider Realistic Rack Capacity
Rack capacity should be evaluated together with cycle time.
A dishwasher that holds a large rack but takes considerably longer to complete the cycle may process fewer racks per hour than a smaller machine with a faster cycle.
Likewise, a machine’s theoretical capacity may differ from its practical capacity because staff need time to scrape dishes, load racks, unload clean items, and replace racks.
Ask the supplier for realistic throughput figures rather than relying only on maximum specifications.
Step 6: Look at Water Consumption
Water consumption is a major operating cost for restaurants.
Commercial dishwasher efficiency is often expressed in gallons per rack or other throughput-based measurements rather than simply gallons per cycle. Current efficiency criteria specify different water-use limits for undercounter, stationary door-type, pot-and-pan, conveyor, and flight-type machines.
This means that when comparing two restaurant dishwashers, you should ask:
- How much water does each rack require?
- How many racks can it process per hour?
- How much water is used during idle periods?
- Does the machine have energy or water-saving modes?
- Does the specification account for the chosen sanitation method?
The lowest water consumption per cycle is not necessarily the lowest water consumption per plate or per customer.
Step 7: Consider Energy Consumption
A commercial dishwasher uses energy for:
- Water heating
- Wash pumps
- Rinse systems
- Tank heating
- Controls
- Drying or heat-management functions
- Standby operation
Commercial efficiency programs therefore evaluate both water consumption and idle energy. Current criteria establish different idle-energy and water-use limits depending on machine category and sanitation method.
This is important because a dishwasher can spend substantial time waiting between service periods while keeping tanks or heating systems warm.
A machine with lower idle energy can therefore reduce operating costs even when it is not actively washing dishes.
Step 8: Do Not Ignore Standby Energy
Restaurants sometimes focus entirely on energy consumed during a wash cycle.
That is a mistake.
A dishwasher can spend significant periods switched on but not actively processing racks.
During these periods, heaters and controls may consume energy.
Commercial efficiency testing specifically accounts for idle energy, including energy used by machine heaters and controls under defined test conditions.
When comparing machines, ask about both:
Energy per operating cycle
and
Idle energy consumption.
Step 9: Check the Restaurant’s Water Supply
Before purchasing a dishwasher, determine whether the restaurant’s plumbing system can support it.
Important considerations include:
- Incoming water temperature
- Water pressure
- Water flow
- Pipe size
- Drain capacity
- Hot-water availability
- Backflow or air-gap requirements
- Local plumbing regulations
A dishwasher cannot perform correctly if the incoming water supply is inadequate.
For high-temperature machines, incoming water temperature can be particularly important because the machine may need to raise the water to the required operating temperature.
The exact requirements must come from the manufacturer’s installation documentation and the applicable local plumbing requirements.
Step 10: Check Electrical Requirements
Commercial dishwashers can have substantially different electrical requirements depending on their heating configuration and size.
Before ordering, verify:
- Voltage
- Phase
- Amperage
- Circuit requirements
- Breaker requirements
- Electrical connection
- Booster heater requirements
- Local electrical code
A machine that cannot be supplied with the correct electrical service is not a bargain.
Always have the electrical requirements checked before finalizing the purchase.
Step 11: Check Whether a Booster Heater Is Required
Some commercial high-temperature installations may use a booster heater to increase incoming water temperature to the level required for sanitizing.
Whether one is necessary depends on the dishwasher design, incoming water temperature, machine configuration, and local requirements.
A booster heater can increase installation and operating costs, so it should be considered before purchasing the machine rather than after installation.
Ask the supplier:
Does this model require a booster heater with our available water temperature?
That single question can prevent an expensive installation surprise.
Step 12: Consider Kitchen Space
Dishwasher capacity is only useful if the machine fits into an efficient workflow.
Measure:
- Machine width
- Machine depth
- Machine height
- Door or hood clearance
- Rack clearance
- Operator access
- Adjacent work surfaces
- Drain location
- Water connection
- Electrical connection
- Chemical storage
- Ventilation requirements
A large dishwasher placed in a cramped corner may technically fit but still create an inefficient kitchen.
The dishwashing station should allow dirty dishes to enter from one direction and clean dishes to leave without unnecessary cross-traffic.
Step 13: Plan the Dirty-to-Clean Workflow
The dishwasher should be part of the restaurant’s overall workflow.
A typical station may include:
Dirty dish collection → scraping → pre-rinse → rack loading → dishwasher → clean rack → drying/air drying → clean storage
The exact layout varies by restaurant, but the principle is important.
Dirty items should not repeatedly cross paths with clean items.
UK food-safety guidance requires food businesses to establish effective cleaning procedures and schedules covering what is cleaned, how often it is cleaned, and which products are used.
The dishwasher therefore should be selected and installed as part of a complete cleaning and sanitation system rather than treated as an isolated appliance.
Step 14: Consider Pre-Scraping and Pre-Rinsing
Restaurant dishwashers work best when excessive food waste is removed before dishes enter the machine.
Large food particles can increase soil load, contaminate wash water more quickly, clog filters, and reduce cleaning effectiveness.
Commercial kitchen guidance recommends scraping food before loading commercial dishwashers and maintaining the equipment properly.
However, excessive manual pre-rinsing can also waste water.
A practical workflow is often to scrape plates thoroughly and use an appropriate pre-rinse process where necessary rather than continuously running large quantities of water over every plate.
Step 15: Look at Filtration and Wash-Tank Management
Commercial machines recirculate wash water during their cycles.
Effective filtration helps remove food particles from the wash system.
The restaurant should understand:
- How the filters are removed
- How frequently they must be cleaned
- Whether staff can clean them easily
- Whether the machine alerts operators to maintenance needs
- How wash water is changed
- How tanks are drained
A dishwasher that is difficult to clean is more likely to be neglected during busy service.
Maintenance convenience should therefore be considered a purchasing feature.
Step 16: Consider Spray Arms and Wash Coverage
The dishwasher should provide effective spray coverage across the rack.
The loading pattern matters as much as the machine itself.
Plates should not be stacked tightly together, bowls should not block one another, and large pans should not obstruct spray arms.
A powerful pump cannot compensate for poor loading.
When evaluating equipment, ask whether replacement spray arms and other wear components are readily available.
Step 17: Choose the Correct Rack System
Commercial racks should match the restaurant’s dishes.
Consider racks for:
- Plates
- Bowls
- Glasses
- Cups
- Cutlery
- Trays
- Utensils
- Specialty cookware
A restaurant may require several rack types.
The cost and availability of racks should be included in the purchase calculation.
A dishwasher can have excellent specifications but still be inconvenient if the restaurant cannot efficiently organize its ware in the available racks.
Step 18: Evaluate Detergent and Rinse-Aid Systems
Commercial dishwashers frequently use professional detergent and rinse-aid systems, and some use automated chemical dosing.
The machine should deliver chemicals at the appropriate rate for the manufacturer’s operating instructions.
Incorrect chemical dosing can lead to:
- Poor cleaning
- Excess foam
- Residue
- Spotting
- Increased chemical costs
- Equipment problems
- Unsatisfactory sanitation
Restaurants should also ensure staff understand chemical handling and storage.
UK workplace guidance emphasizes managing risks associated with cleaning and disinfecting chemicals, including appropriate controls for employee exposure.
Step 19: Check Chemical Availability
Before choosing a chemical-sanitizing dishwasher, make sure the required chemicals are readily available in your area.
Ask:
- What sanitizer does the machine require?
- What detergent does it require?
- What rinse aid is recommended?
- How frequently must chemicals be replaced?
- Is automatic dosing included?
- How is sanitizer concentration checked?
- Is technical support available?
A machine that depends on specialized chemicals that are difficult to obtain can become a serious operational problem.
Step 20: Consider Water Hardness
Hard water can create mineral scale inside commercial dishwashers.
Scale can accumulate on:
- Heating elements
- Spray components
- Internal surfaces
- Pipes
- Valves
- Pumps
This can reduce efficiency and increase maintenance requirements.
If the restaurant is located in a hard-water area, consider whether the installation requires:
- Water softening
- Filtration
- Scale control
- Regular descaling
The correct approach depends on the local water characteristics and the dishwasher manufacturer’s requirements.
Step 21: Check Drying Requirements
A restaurant does not necessarily need dishes to be completely dry immediately after the cycle, but it does need a practical system for handling cleaned ware.
Some restaurants rely primarily on the final rinse temperature and air drying.
Others may need specific drying arrangements depending on the type of equipment.
The important principle is that cleaned and sanitized items should be handled and stored in a way that prevents recontamination.
The restaurant’s cleaning procedures should cover utensils, dishes, and cooking equipment and specify how and when cleaning is performed.
Step 22: Consider Noise
Noise may not be the first concern in a restaurant, but it can still matter.
A dishwasher located close to the dining room, bar, or open kitchen can contribute to the overall noise level.
A machine located in a dedicated back-of-house dishwashing room may have less impact on customers.
If the restaurant has an open kitchen, noise should be included in the equipment comparison.
Step 23: Compare Reliability and Service Support
A commercial dishwasher is a critical piece of restaurant equipment.
If it stops working during dinner service, the consequences can be significant.
Before buying, investigate:
- Local service technicians
- Parts availability
- Warranty coverage
- Response time
- Preventive-maintenance options
- Emergency repair support
- Availability of pumps
- Availability of heating components
- Availability of seals and gaskets
- Availability of control components
A dishwasher with excellent specifications but poor local support may be a worse investment than a slightly more expensive model that can be repaired quickly.
Step 24: Calculate Total Cost of Ownership
Never compare restaurant dishwashers based only on purchase price.
The total cost includes:
Purchase + installation + utilities + detergent + rinse aid + sanitizer + maintenance + repairs + labour + downtime.
Energy-efficient commercial equipment can reduce utility expenses, and current efficiency programs report significant potential savings from qualifying commercial dishwasher models.
A more expensive machine can therefore become the cheaper machine over its working life if it uses less water, less energy, requires less maintenance, or reduces labour requirements.
Step 25: Look for Energy-Efficient Equipment
Energy efficiency is particularly important in restaurants because commercial kitchens can have substantial energy demands.
Restaurants are among the more energy-intensive commercial building types, making efficient kitchen equipment an important part of overall energy management.
When comparing commercial dishwashers, look for independently verified efficiency information rather than relying only on marketing descriptions.
For qualifying commercial dishwashers, efficiency criteria address both water consumption and idle energy.
Step 26: Compare Water Consumption Per Rack
Do not simply ask:
“How many gallons does this dishwasher use?”
Ask:
“How much water does it use per rack at the required operating condition?”
Commercial machines are categorized according to throughput and water consumption, with different criteria for undercounter, stationary door, conveyor, and flight-type machines.
This makes water per rack one of the most useful numbers when comparing commercial dishwashers.
Step 27: Consider the Restaurant’s Menu
The menu affects dishwasher requirements.
A fine-dining restaurant may have:
- Large quantities of plates
- Multiple small courses
- Delicate glassware
- Numerous cutlery pieces
- Presentation dishes
A casual restaurant may have:
- Heavy plates
- Bowls
- Cups
- Serving dishes
A pizza restaurant may have:
- Plates
- Pizza trays
- Dough equipment
- Pans
A bar may have a much higher glasswashing requirement.
A restaurant serving large amounts of cooked food may need additional pot-and-pan capacity.
Dishwasher selection should therefore follow the menu and service model.
Step 28: Consider Glassware Separately
If beverages are a major part of sales, calculate glassware demand separately.
A restaurant can have sufficient plate-washing capacity and still suffer from a glass shortage.
Ask:
- How many glasses are used per hour?
- How many types of glasses are used?
- Are glasses fragile?
- How quickly must they return to the bar?
- Does the restaurant need dedicated glasswashing?
A separate glasswasher can sometimes solve a problem that a larger general dishwasher would not solve efficiently.
Step 29: Consider Pots and Pans Separately
Heavy cookware can consume a surprising amount of dishwashing capacity.
Large pots and pans take up substantial rack space and may prevent plates and glasses from being loaded efficiently.
If cookware volume is high, determine whether a separate pot-and-pan washer is more efficient.
Commercial equipment standards specifically recognize pot, pan, and utensil machines as a distinct category, reflecting the different requirements of heavy cookware washing.
Step 30: UK Restaurant Dishwasher Considerations
Restaurants in the UK need to ensure that their cleaning and disinfection procedures are effective and properly documented.
Food businesses must have cleaning schedules covering what needs to be cleaned or disinfected, how frequently it is cleaned, and which products are used.
Commercial dishwasher performance should also be monitored appropriately. Current local-authority guidance recommends commercial dishwasher temperatures above 81°C for effective disinfection and emphasizes maintaining the machine and using suitable detergent.
UK businesses should also consider the applicable commercial equipment performance standards when selecting equipment. Current UK efficiency testing requirements reference commercial dishwasher performance and hygiene standards including BS EN IEC 63136 and BS EN 17735.
Because food-safety enforcement involves local authorities, restaurants should verify any specific requirements that apply to their premises and food operation.
Step 31: U.S. Restaurant Dishwasher Considerations
U.S. restaurants should select commercial equipment appropriate for the applicable local and state food-code requirements.
Commercial dishwashers are a distinct equipment category, with commercial sanitation and efficiency requirements differing from residential appliances. Commercial equipment may be evaluated under recognized commercial warewashing standards, while efficiency criteria distinguish different commercial dishwasher types and sanitation methods.
Restaurant operators should therefore confirm:
- Commercial certification
- Sanitation method
- Required temperatures
- Water supply
- Drainage
- Electrical requirements
- Local health-code requirements
- Chemical requirements
The applicable local health authority should be consulted before finalizing a machine when there is uncertainty.
Step 32: Canadian Restaurant Dishwasher Considerations
Canadian requirements can vary between provinces and local jurisdictions.
Ontario, for example, specifies requirements for mechanical dishwashers covering wash-water temperature, sanitizing-rinse temperature or chemical sanitization, and temperature indication, while providing specific treatment for appropriately certified commercial machines.
This demonstrates why restaurant owners should not assume that one dishwasher specification automatically satisfies every Canadian jurisdiction.
Before buying, confirm the applicable provincial and municipal requirements.
A commercial dishwasher that is appropriately certified and installed according to the relevant requirements can make compliance considerably more straightforward.
Step 33: Check Dishwasher Temperature Monitoring
Temperature monitoring should be considered part of the purchasing decision.
A commercial dishwasher should provide an appropriate means of determining whether required wash and rinse conditions are being achieved.
Ontario’s requirements, for example, specifically address thermometers showing wash and rinse temperatures and their accessibility, subject to the stated commercial-certification provision.
UK local guidance likewise recommends using temperature displays and periodic checks with temperature strips or stickers where appropriate.
A machine that makes temperature monitoring easy is generally preferable to one that leaves operators uncertain about whether the required conditions are being achieved.
Step 34: Consider Staff Training
Even the best commercial dishwasher cannot compensate for poor operating procedures.
Employees should understand:
- How to scrape dishes
- How to load racks
- How to select the correct cycle
- How to use detergent
- How to use rinse aid
- How to handle sanitizer
- How to check temperatures
- How to clean filters
- How to drain tanks
- How to identify problems
- How to store clean dishes
Food businesses are expected to demonstrate effective cleaning procedures, making staff training an important part of the overall sanitation system.
Step 35: Create a Dishwasher Maintenance Schedule
Restaurant dishwashers should be maintained according to manufacturer instructions and the restaurant’s sanitation procedures.
A practical maintenance schedule can include:
Every Shift
- Remove food debris
- Clean filters
- Check detergent
- Check rinse aid
- Check sanitizer where applicable
- Inspect spray arms
- Check temperatures
- Drain the machine according to instructions
Daily
- Clean internal surfaces
- Clean door seals
- Inspect nozzles
- Check racks
- Clean surrounding areas
Weekly
- Inspect spray arms
- Inspect filters
- Check chemical lines
- Inspect hoses
- Check for leaks
- Look for mineral scale
Periodically
- Descale as required
- Service pumps
- Inspect heating components
- Check temperature controls
- Inspect chemical dosing
- Replace worn components
The exact schedule should always follow the manufacturer’s instructions and the restaurant’s food-safety procedures.
Step 36: Think About Downtime
Downtime has a financial cost.
If the dishwasher stops working during peak service, employees may need to wash dishes manually.
That can increase:
- Labour costs
- Water consumption
- Service delays
- Staff stress
- Risk of running out of clean dishes
For a busy restaurant, service support can therefore be almost as important as machine specifications.
Before buying, ask how quickly a qualified technician can reach the restaurant.
Step 37: Ask About Spare Parts
Important spare parts can include:
- Pumps
- Heating elements
- Thermostats
- Sensors
- Solenoid valves
- Door seals
- Spray arms
- Filters
- Control boards
- Chemical pumps
Parts availability can determine whether a breakdown lasts two hours or two weeks.
A restaurant should prefer equipment with reliable local parts distribution.
Step 38: Do Not Choose Based on Cycle Time Alone
A very short cycle sounds attractive.
But the shortest cycle is not necessarily the best cycle.
Ask:
- Does the cycle achieve the required sanitation?
- Does it provide sufficient cleaning?
- What is the rack capacity?
- What is the water consumption?
- What is the energy consumption?
- What is the actual throughput?
- Is the cycle suitable for the restaurant’s soil load?
A dishwasher that completes an extremely fast cycle but produces poor results is not efficient.
The goal is fast, consistent, compliant cleaning and sanitizing, not merely fast machine operation.
Step 39: Compare Machines Using a Buying Checklist
Before purchasing, compare each machine using the same criteria.
| Feature | Dishwasher A | Dishwasher B | Dishwasher C |
|---|---|---|---|
| Machine type | |||
| Rack capacity | |||
| Cycle time | |||
| Racks/hour | |||
| Water/rack | |||
| Energy use | |||
| Idle energy | |||
| Sanitation method | |||
| Certification | |||
| Booster heater | |||
| Electrical requirements | |||
| Water requirements | |||
| Drain requirements | |||
| Chemical system | |||
| Noise | |||
| Warranty | |||
| Local service | |||
| Parts availability | |||
| Purchase price | |||
| Installation cost | |||
| Estimated operating cost |
This makes the decision much more objective.
Step 40: Calculate Cost Per Rack
One of the best ways to compare commercial dishwashers is to estimate cost per rack.
Consider:
Water cost per rack + electricity cost per rack + detergent + rinse aid + sanitizer + maintenance
Then multiply that figure by the number of racks processed each day.
This can reveal why a slightly more expensive machine may be financially attractive over several years.
Commercial efficiency programs specifically provide water and energy performance information for different dishwasher categories, allowing operators to compare machines on more than purchase price.
Step 41: Avoid Buying Too Small
Buying an undersized dishwasher is one of the most expensive mistakes a restaurant can make.
A small machine may look attractive because it costs less.
But if staff constantly wait for clean racks, the restaurant loses productivity.
Signs that a dishwasher is too small include:
- Dirty dishes accumulating
- Clean dishes running out
- Staff waiting for cycles
- Multiple racks waiting in line
- Manual washing becoming necessary
- Glass shortages
- Cookware washing becoming a bottleneck
The machine should have enough capacity for peak demand rather than only average demand.
Step 42: Avoid Buying Too Large
Oversizing can also be a problem.
An unnecessarily large dishwasher can consume more space, require greater infrastructure, cost more to purchase, and potentially use more resources than necessary.
A small café does not normally need the same equipment as a hotel banquet kitchen.
The correct approach is to select the smallest machine that comfortably handles the restaurant’s peak workload with an appropriate operating margin.
Step 43: Choose a Dishwasher That Fits Your Growth Plans
Restaurant businesses can grow.
If you currently serve 100 customers but expect to expand to 200, buying equipment that barely handles today’s workload may result in another major investment later.
Consider:
- Planned seating expansion
- Additional meal periods
- Catering
- Delivery growth
- Events
- Additional menu items
- Increased beverage sales
However, do not dramatically oversize the machine based on speculative growth.
Use realistic business forecasts.
Step 44: What Dishwasher Should a Small Restaurant Buy?
For a small restaurant, an undercounter or compact door-type commercial dishwasher may be appropriate depending on the number of racks required during peak service.
The decision should be based on:
- Peak customers
- Dish volume
- Available kitchen space
- Cycle time
- Required sanitation method
- Utility availability
Commercial efficiency criteria specifically recognize undercounter and stationary door-type machines as separate categories, making them practical options for different small and medium-sized operations.
What Dishwasher Should a Medium Restaurant Buy?
A medium restaurant may benefit from a door-type machine if it has substantial dish volume but limited floor space.
If demand becomes high enough that racks are continuously waiting, a conveyor system may be more appropriate.
The key indicator is throughput.
When the dishwasher station consistently becomes the limiting step in kitchen operations, it may be time to increase capacity.
What Dishwasher Should a Large Restaurant Buy?
Large restaurants may require conveyor or flight-type equipment depending on their throughput.
Hotels, banquet kitchens, institutional kitchens, and very high-volume restaurants can process large quantities of ware continuously, making conveyor and flight-type systems more appropriate than small stationary machines.
The installation should be designed as part of the entire kitchen layout rather than added after construction.
What Is the Best Restaurant Dishwasher?
There is no single best restaurant dishwasher for every business.
The best machine is the one that:
- Handles peak demand
- Provides appropriate sanitation
- Fits the kitchen
- Works with available utilities
- Uses resources efficiently
- Has reliable service support
- Has available spare parts
- Matches the restaurant’s menu
- Fits the budget
- Meets applicable regulations
A dishwasher that is perfect for a small café may be completely unsuitable for a 500-seat restaurant.
Restaurant Dishwasher Buying Mistakes to Avoid
Choosing Based Only on Price
The cheapest dishwasher may have higher lifetime operating costs.
Choosing Based Only on Cycle Time
A fast cycle does not automatically mean adequate cleaning or sanitation.
Ignoring Peak Demand
Average demand can hide the actual bottleneck.
Ignoring Installation Requirements
Water, drainage, electrical capacity, and heating must be confirmed before purchase.
Ignoring Certification
A commercial restaurant should verify that the machine is appropriately certified for its intended application.
Ignoring Local Regulations
UK, U.S., and Canadian requirements can differ.
Ignoring Service Support
A broken dishwasher during dinner service can be extremely expensive.
Ignoring Water Quality
Hard water can increase scale and maintenance.
Choosing the Wrong Machine Type
An undercounter machine may be inadequate for a high-volume restaurant, while a conveyor may be excessive for a small café.
Restaurant Dishwasher Buying Checklist
Before placing an order, confirm all of the following:
Capacity
- What is the peak number of customers?
- How many racks are required per hour?
- What types of dishes are being washed?
- How much glassware is generated?
- How much cookware is generated?
Sanitation
- High-temperature or chemical?
- What certification does the machine have?
- What temperature or chemical concentration is required?
- How are conditions monitored?
Utilities
- Voltage?
- Phase?
- Amperage?
- Water pressure?
- Water temperature?
- Drain requirements?
- Booster heater?
- Ventilation?
Efficiency
- Water per rack?
- Energy per cycle?
- Idle energy?
- Chemical consumption?
Installation
- Available space?
- Door or hood clearance?
- Rack storage?
- Drain location?
- Chemical storage?
- Workflow?
Maintenance
- Filter cleaning?
- Descaling?
- Chemical-system maintenance?
- Spare parts?
- Service availability?
Financial
- Purchase price?
- Installation cost?
- Utility cost?
- Chemical cost?
- Maintenance cost?
- Warranty?
- Expected downtime?
Frequently Asked Questions
What size dishwasher do I need for a restaurant?
The required size depends primarily on peak dishwashing demand rather than restaurant floor area. Calculate how many racks need to be processed during the busiest service period and choose a machine capable of handling that volume with an appropriate operating margin. Commercial dishwasher sizing is closely related to the number of people served and the volume of food service.
What type of dishwasher is best for a small restaurant?
An undercounter or compact door-type commercial dishwasher is often suitable for a small restaurant, provided its rack capacity and cycle time can handle peak demand. Undercounter and stationary door machines are recognized as separate commercial dishwasher categories with their own efficiency characteristics.
What type of dishwasher is best for a large restaurant?
Large, high-volume restaurants may need a conveyor or flight-type dishwasher. The correct choice depends on the number of racks or ware that must be processed during peak service and the available kitchen space.
Is a high-temperature dishwasher better than a chemical dishwasher?
Neither is universally better. High-temperature machines use heat for sanitizing, while chemical machines use an approved sanitizing solution. The correct choice depends on local regulations, available utilities, energy costs, chemical handling, certification, and restaurant workflow.
What temperature should a commercial dishwasher reach?
The required temperature depends on the dishwasher type, sanitation method, certification, and local requirements. For example, Ontario’s food-premises regulation specifies a water sanitizing rinse of at least 82°C for the applicable water-based route, while commercial certification can alter how certain requirements apply.
Does a restaurant dishwasher need to be certified?
Restaurants should choose equipment appropriately certified for commercial warewashing and verify the requirements applicable to their jurisdiction. Commercial dishwasher performance is evaluated under dedicated commercial standards rather than household dishwasher requirements.
How fast should a restaurant dishwasher be?
There is no universal ideal cycle time. The important number is how many racks the machine can realistically process during peak service while achieving appropriate cleaning and sanitation. Some professional machines have very short cycles, but actual performance varies by machine and program.
How much water does a commercial dishwasher use?
Water consumption varies significantly by machine type. Commercial efficiency specifications measure water consumption using metrics such as gallons per rack, gallons per square foot of rack, or gallons per hour depending on the machine category.
How can I reduce restaurant dishwasher water consumption?
Choose an efficient machine, scrape food before loading, avoid unnecessary pre-rinsing, fully load racks without blocking spray patterns, maintain filters and spray arms, and operate the machine according to manufacturer instructions. Efficient commercial machines can substantially reduce water consumption compared with standard models.
How can I reduce restaurant dishwasher energy use?
Choose an efficient commercial dishwasher, minimize unnecessary idle operation where permitted by the equipment instructions, maintain heating systems, and select the sanitation method appropriate for the restaurant’s infrastructure. Commercial efficiency standards specifically address idle energy and operating water consumption.
Should I buy an ENERGY STAR commercial dishwasher?
An independently verified efficiency label can be useful when comparing commercial equipment because it provides standardized criteria for energy and water performance. Current qualifying commercial dishwasher criteria cover multiple machine types and sanitation approaches.
Do commercial dishwashers need hot water?
Requirements vary by machine and sanitation method. High-temperature systems require appropriate heating capability, while chemical-sanitizing systems rely on a chemical sanitizer under specified operating conditions. The restaurant should follow the manufacturer’s installation requirements and applicable local regulations.
Does a restaurant dishwasher need a booster heater?
Not necessarily. Some machines have suitable internal heating systems, while others may use or require a booster heater depending on incoming water temperature and machine configuration. Confirm this before purchasing.
How often should a restaurant dishwasher be cleaned?
Commercial dishwashers should be cleaned according to the manufacturer’s instructions and the restaurant’s food-safety procedures. Filters, tanks, spray arms, doors, and other components generally require routine attention. Food businesses should have documented cleaning schedules covering what is cleaned, how often it is cleaned, and which products are used.
Should restaurant dishes be scraped before going into the dishwasher?
Yes. Removing excess food before loading reduces the soil entering the machine and helps the dishwasher operate effectively. Commercial kitchen guidance specifically recommends scraping food before loading commercial dishwashers.
Should restaurant dishes be pre-rinsed?
A suitable pre-rinse or scraping procedure can be useful for heavily soiled dishes, but excessive running-water pre-rinsing can waste water. The restaurant should establish a practical procedure based on the dishwasher, soil level, and manufacturer instructions.
Do restaurants need a separate glasswasher?
Not always. A general commercial dishwasher may handle glassware, but a separate glasswasher can be useful where beverage volume is high and rapid glass turnover is essential.
Do restaurants need a separate pot-and-pan washer?
Not always. A standard commercial dishwasher may handle some cookware, but restaurants with substantial pot, pan, tray, and utensil volumes may benefit from dedicated equipment. Commercial standards recognize pot, pan, and utensil machines as a separate category.
Is an undercounter dishwasher enough for a restaurant?
It can be enough for a small restaurant, café, or bar with moderate dish volume. The deciding factor is whether its actual rack throughput can handle peak demand.
Is a conveyor dishwasher better than a door-type dishwasher?
A conveyor machine can be better for high-volume operations because it is designed around greater throughput. A door-type machine can be more practical for restaurants with moderate volume and limited space.
What should I look for in a restaurant dishwasher warranty?
Look for coverage on major components, labour, heating systems, pumps, controls, and other critical parts. Also investigate the availability and response time of authorized service technicians in your area.
How important is local dishwasher service?
Very important. A restaurant dishwasher is operationally critical, and extended downtime can force staff to wash dishes manually and disrupt service. Local service availability should be evaluated before purchasing.
Does hard water affect restaurant dishwashers?
Yes. Hard water can contribute to mineral scale, particularly on heating components and water-contact surfaces. Restaurants in hard-water areas should ask about water treatment and descaling requirements.
What detergent should a restaurant dishwasher use?
Use detergent specifically designed and approved for the commercial dishwasher and follow the machine manufacturer’s dosing instructions. Chemical requirements vary between machines and sanitation systems.
Can household dishwasher detergent be used in a commercial dishwasher?
It should not be assumed to be compatible. Commercial machines are generally designed around specific detergent, rinse-aid, and, where applicable, sanitizer systems.
What should I do if the restaurant dishwasher is not sanitizing properly?
Stop relying on the machine until the problem is investigated. Check the operating temperatures or sanitizer concentration according to the machine’s procedures, inspect filters and spray components, verify chemical supply, and contact qualified service personnel when necessary. Food businesses are responsible for ensuring that cleaning and disinfection procedures are effective.
How do I know if my dishwasher is too small?
If dirty racks regularly accumulate, staff wait for cycles, clean dishes run out during service, or employees frequently resort to manual washing, the machine may not have enough practical capacity for the restaurant’s peak demand.
How do I know if my dishwasher is too large?
If the machine occupies excessive kitchen space, requires substantially more utilities than necessary, and operates far below its intended throughput, it may be oversized. The goal is sufficient capacity with a reasonable margin rather than maximum possible capacity.
Should a restaurant buy a dishwasher based on the number of seats?
Seats can provide a useful starting point, but they are not enough. Customer turnover, meal periods, menu style, dish type, glassware volume, cookware, and peak service demand are all important.
Is dishwasher efficiency really important for restaurants?
Yes. Restaurants operate energy-intensive kitchens, and commercial dishwashers can consume significant amounts of water and energy. Efficient models can reduce operating costs over the equipment’s working life.
What is the most important feature when choosing a restaurant dishwasher?
There is no single feature. The most important consideration is whether the complete system can reliably meet the restaurant’s peak dishwashing demand while achieving the required cleaning and sanitation performance.
Final Verdict: How to Choose the Right Dishwasher for a Restaurant
Choosing a restaurant dishwasher should begin with workload, not brand or price.
First determine how many dishes, glasses, utensils, pots, and pans must be processed during the busiest period. Then determine the required rack throughput. From there, select the appropriate machine category—undercounter, door-type, conveyor, flight-type, glasswasher, or pot-and-pan equipment. Commercial dishwasher standards distinguish these categories because their capacity, water consumption, energy requirements, and operating characteristics are different.
Next, determine whether high-temperature or chemical sanitizing is appropriate. Check commercial certification and verify the sanitation requirements applicable to your location. Requirements can differ between the UK, individual U.S. jurisdictions, and Canadian provinces, so restaurant owners should not assume that a machine acceptable in one location automatically satisfies the rules in another. Ontario’s requirements, for example, specifically address mechanical dishwasher temperatures and commercial certification, while UK guidance emphasizes effective cleaning, appropriate disinfection conditions, and monitoring.
After that, examine water and energy consumption. Look beyond the purchase price and compare water per rack, energy use, idle energy, chemical consumption, maintenance requirements, and service costs. Efficient commercial dishwashers can provide meaningful savings over their operating life, making lifetime cost more useful than initial price alone.
Finally, make sure the dishwasher fits the kitchen physically and operationally. It should be positioned so dirty dishes can enter efficiently, clean dishes can leave without unnecessary cross-traffic, staff can load racks easily, filters and spray arms can be maintained, and the machine can be serviced without disrupting the entire kitchen.
For a small restaurant, start by evaluating an undercounter or door-type commercial machine. For a medium-volume restaurant, consider a door-type machine and compare it with a conveyor if rack demand is high. For a large restaurant, hotel, banquet kitchen, or institutional operation, investigate conveyor or flight-type systems.
The best restaurant dishwasher is not necessarily the biggest, fastest, or cheapest machine. It is the machine that provides the right combination of capacity, sanitation, reliability, efficiency, installation compatibility, service support, and total cost of ownership for your particular restaurant.
When those factors are evaluated together, the dishwasher becomes more than a piece of kitchen equipment. It becomes an important part of the restaurant’s productivity, food-safety system, and long-term operating costs.
