Buying Warewashing Equipment
If you have the budget and the space, then it is recommended that an establishment has a glasswasher and a dishwasher. Although one machine can be used for both glasswashing and plate washing, there are problems with putting everything in one machine. Your warewashing system will be one of the hardest working systems in the kitchen, so it's worth investing in it. The main problem is that combining the use will not give good results due to grease from the tableware contaminating glassware. Chemicals used for cleaning tableware are different to those used in Glasswashers. Also dishwasher rinse at a higher temperature which could crack glasses. Using the same machine to wash both dishes and glasses is a compromise which will give unsatisfactory results.
Choosing the Size of the Machine
Many small to medium businesses underestimate the capacity of warewashing machine they need. Many businesses choose warewashing machines on the average overall daily output, which is a mistake as they don't consider the peak demand times in the day when tableware and glassware is needed quickly. Also, by buying a machine for current needs, an establishment makes no allowance for an increase in business. Warewashers are rated by the number of dishes or racks (at about 20 dishes per rack) they can wash per hour. To determine the size of the dishwasher needed, first estimate how many dishes each customer uses. Check the overall height of your glasses or dishes and choose a machine which will accommodate them. Most undercounter machines come in basket sizes of: Glasswashers use square baskets 350mm, 400mm, 450mm and 500mm. Generally Dishwashers use square baskets sizes of 450mm or 500mm. Typically a 500mm basket will accommodate 14-16 plates or 20-24 cups per wash cycle.
Expected Number of Customers
Simply multiply the number of expected customers per hour by the dish count per customer to find the number of dishes you will use per hour. Then divide this by the rack size to get the number of racks per hour the warewasher needs to be able to process.
There are strict 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. Basically Glasswashers can only be connected to mains water supply through a WRAS approved no return valve. Dishwashers are classified as a higher contamination risk and can only be connected to mains water supply by an WRAS approved Class “A” air gap, basically this is a minimum 4” air gap between the water in the machine and the cold water main. This is usually achieved by a separate break tank or one integrated into the back of the machine.
Choose the Right Machine
Glassware washes in a much shorter time, so by putting glasses in with the longer wash cycle needed for tableware wastes energy. As well as this, food debris from tableware can easily cause smears and marks on glassware, leading to the need for hand finishing or re-washing. Even if you were to put glassware through on a separate wash after a tableware cycle, it could still produce soiled glassware. Dishwashers are often programmed to do a pre-rinse cycle to clear loose food waste stuck to plates and may have a high finishing hot rinse to aid sanitisation.
Glasswashers are normally front-loading compact machines for small to moderate usage of glassware. They will often be found fitted under a counter or on a bench in a preparation area and have a fast turnaround on soiled glasses. While they can often be found underneath the bar because of space restrictions, it is better to use the bar area for retailing rather than glasswashing. Busy pubs and bars may need to move to a pull-down hood machine which enables rapid washing of a large volume of glasses.
Whereas domestic dishwashers are usually designed to perform one wash per day, a commercial machine is designed to go through 30 washes or more per day. As throughput increases, the cycle time of the machine becomes a critical factor and domestic machines struggle to keep up with demand.
Front Loading Dishwashers
Compact Dishwashers are available in various sizes, starting with compact machines, which look and work in a similar way to glasswashers. Like glasswashers, these are designed to fit on a bench in a back-of-house cleaning area, still-room or satellite kitchen. These are in fact Glasswashers as they have a short wash cycle and usually are of a low amperage with slow recovery times between wash cycles. These machines are only suitable for washing glasses and clean plateware. They are not suitable for tea cups or coffee cups or heavily soiled plates. The wash cycle is too short which will allow tanning to build up in cups and on cutlery. The larger 450mm and 500mm Dishwashers have longer wash cycles and are suitable for all tableware or as large glasswashers. Some of these machines come with electronic programing and variable wash cycles. Also available as gravity or drain pumped machines with options for built in water softener and Class A air gaps.
If you have a very busy establishment you should consider a hood machine. These are more powerful, faster and are manually loaded with a basket of soiled tableware. They are usually configured with stainless steel tabling either side of the dishwasher so while a basket of dirty tableware is being washed, another basket of dirty tableware is being loaded ready to go in and a washed basket on the other side of the hood washer is waiting to be emptied. This gives a continual cycle of plate washing. It is more user friendly for the operator and minimises the need to carry heavy baskets and load into the machine. They do however take up more space and are more expensive to purchase due to the side tabling required, however a well designed dirties table with sink and cleans table can be fitted to the machine either in a straight line configuration or corner configuration and can include pre-wash spray and racking to store empty baskets and even draining racking above the cleans table to take the clean baskets while they dry off.
Rack Conveyor Dishwashers
Rack conveyor dishwashers work on a pass-through system where the baskets of soiled tableware are on a conveyor belt which passes through the washing machine, going through wash zones which start at pre-rinse, go to hot wash, then hot rinse and come out on the other side of the conveyor ready for stacking away.
To summarise when choosing your machine take into account:
Type of machine within your budget. The cheapest is not always the best buy.
How many items an hour you want to wash
Size and height of the items
The location of the machine, Drain type, electrical power available, water supply.
Water hardness ( do you need a water softener)
Access to the location, some larger machines may not go through doorways etc.
Recommended manufacturers: Classeq, Dawson, Halcyon, Meiko, Proton, Sammic. These are machines we have personal experience with over the last 25 years. For further help and advice contact us and we will be pleased to provide information and quotations for installations and machines