For hands that do dishes

Chefs may not gaze in admiration at their dishwashers in the same way they might a gleaming bespoke island cooking suite, but warewashing is every bit as important in the kitchen routine. That importance is not just in delivering clean tableware and glassware but, increasingly, in doing its job with cost efficiency.

The capital cost of buying warewashing equipment is not inconsiderable, but deciding on the type and size of machine and then looking for the cheapest price among the brands is a mistake. "The whole-life cost is what really matters - energy, water and detergent costs, servicing and how robust the machine is, and its expected working life are more important cost issues than purchase price when the number of wash cycles a machine will go through in a year are reckoned up," advises Terry Stack, marketing manager for Electrolux and Zanussi warewashing systems.

At Marsh UK, one of the world's largest risk-management and insurance companies, building services manager Eddie Boddy had to justify the investment in a new dishwasher for the staff restaurant at the company's head office in Witham, Essex.

Whichever machine he chose to wash the dishes for 900 staff not only had to do the job, but be cheaper to run than the existing system. "Energy saving was part of the buying brief - not just for the cost factor, but so we could say we had taken steps to reduce our energy consumption."

The choice of machine for Boddy was a Meiko K200VP rack-system dishwasher. The water- and energy-saving feature he liked was an additional rinse installed behind the prewash zone which uses the clean water from the final rinse at the end of the wash cycle to flush off more residual food waste on tableware. This halves the amount of detergent needed by a wash cycle compared with a machine not fitted with this clean water recycling system.

And, as with many modern dishwashers, the Meiko K200VP uses heat exchangers that take hot air exhaled by the dishwasher to preheat incoming cold water, so reducing energy consumption.

Increased versatility is how the Dawson Foodservice Equipment range of Commenda-branded machines is addressing energy efficiency. "Dawson Foodservice and Commenda have utility costs as a key task for our designers, and it's not just a UK issue, but a global one," says sales and marketing director Robin McKnight.

Dawson has just introduced the LF range of front-loading dishwashers to the UK which, despite being a machine for small to medium throughput, has a higher-than-usual wash cabinet which can take large cover plates, flatware and - on the biggest model in the LF range - trays and large serving dishes.

If heated wash water loses temperature during the wash cycle then thermostats will activate heating elements, which are a big drain on energy consumption. UK warewashing manufacturer Classic has tackled this energy cost issue by making its new S Series machines double-skinned to keep heat in and to operate with maximum efficiency.

The design also means a reduction in the amount of water needed for the initial fill compared with equivalent machines, which Classic sales director Chris Nowlan says can offer a 60% saving on water consumption and still deliver clean baskets at the end of the wash cycle. He claims that washing a rack of dishes in an S Series machine has a running cost of 4.5p per cycle, including detergent.

Flexibility in the way warewashing systems are configured in the kitchen is another way of containing cost. Expansion from 100 seats to 450 in the Galleries coffee shop in the County Durham port of Hartlepool meant that the existing dishwasher was unable to cope with the volume.

A full-rack dishwasher was needed, but the dishwash area was so small that a straight, in-line system could not be installed. Galleries group manager Barbara Meredith worked with distributor CNG Foodservice Equipment to have a new warewashing unit built in a U-shape, using two identical, more compact machines in the two corners of the wash area, but connected with tabling. With this, the same wash throughput could be achieved as with a larger in-line system. Machines chosen were two Winterhalter 502 pass-through models, which gave the configuration flexibility to avoid costly rebuilding or relocation. The tabling between the two washers is useful for unloading washed baskets, while the other two arms of tabling feed in soiled baskets.

The warewashing industry often takes the hourly rinse water consumption as a benchmark for measuring energy efficiency, since less water per hour means not only economies in water consumption but also reduced energy requirements for water heating. But Tim Bender, UK product development manager at Hobart, says there is more to consider when evaluating energy efficiency. He argues that features such as continuous filtration to remove debris throughout the wash cycle - as Hobart fits to its single-tank machines - keeps the water cleaner for longer, which reduces the number of times the machine is drained and refilled with wash water.

Yet while machine design plays a big role in energy efficiency, Les Starling, service manager for the Parry Group, believes it's often the caterer who causes the biggest drain on cost efficiency by failing to fit a water-softening system. The result is furring on heating elements, causing them to become inefficient and leave smearing and salty deposits on glassware and tableware, which then requires either rewashing or hand-finishing.

Training of staff to use warewashing equipment with respect is not an obvious cost saving, but a very real one, according to John Nelson, managing director of Nelson Dish and Glasswashing Machines.

Machines used as ashtrays or waste disposal units can quickly rack up big service and repair bills.

Warewasher types

• Glasswashers tend to be front-loading, compact machines for small-to-moderate usage, often fitting under a counter or on a bench, and providing a fast turnaround of soiled glasses, so avoiding the need for heavy stocking levels.
• Cabinet dishwashers (such as the Hobart FX300, below) are compact machines which look and work in a similar way to glasswashers and are designed to fit on a bench in a back-of-house cleaning area or under a counter in a still room or satellite kitchen.
• Pull-down hood machines are more powerful and faster and are manually loaded with a basket of soiled tableware. They are often configured with stainless-steel tabling either side of the washer, so while a basket of dirty tableware is being washed, another basket is being loaded ready to go in, and a washed basket on the other side is being emptied, giving a continual cycle of plate washing.
• Rack conveyor dishwashers work on a pass-through system where the baskets of soiled tableware are on a conveyor belt which passes through the machine's wash zones starting at pre-rinse, going to hot wash, then hot rinse, and coming out on the other side of the conveyor ready for stacking away.
• Flight dishwashers provide a semi-automatic dishwashing system, similar in principle to rack conveyor systems, but much bigger. They are designed to cope with huge volumes of soiled tableware in establishments such as universities, hospitals, airline food production kitchens, large staff-feeding facilities and conference and exhibition centres.

Consider before you buy…

SIZE Many small-to-medium businesses underestimate the capacity of warewashing machine they need. The big mistake is looking at the overall daily throughput and basing machine size choice on that. This ignores the fact there are always peak demand times in the day when tableware and glassware is needed quickly. Also, buying a machine for current needs makes no allowance for an increase in business.

REGULATIONS There are strict national regulations on how dishwashers and glasswashers should be connected to the water main to prevent contamination of the mains water system through accidental backflow of dirty water. Some cheaper machines may not fully comply with water supply regulations, involving costly modifications later. Check that the machine complies.

CONSTRUCTION
Ask about the type of steel. All warewashing machines offer stainless-steel wash tanks, but there are different grades used in their manufacture. The best is grade 304, much more corrosion-resistant than the cheaper, grade 430 stainless steel, though both look the same.

Ask, too, about noise and heat emissions. Double-skin casings will reduce noise and operating cost and be cool to the touch.

Get advice on the fitting of a water-treatment system to prevent limescale build-up in the internal pipework of the machine. Water treatment is essential in hard-water areas and recommended in other areas.

PERFORMANCE Study the energy and water consumption performance. What may seem a cheap machine to buy could prove to be an expensive machine to run.

Be specific about the availability of spare parts, the turnaround time for spares and the service options offered with the machine.

Source: CESA- the Catering Equipment Suppliers' Association

Contacts

CESA 020 7233 7724
Classic 01889 272300
Dawson Foodservice 01226 350450
Electrolux 0121-220 2800
Fagor 01732 860360
Hobart 07002 101101
Meiko 01753 561561
Nelson 0800 592833
Parry Group 01332 875544
Winterhalter 01908 359030
Zanussi 0121-220 2800