How to choose a dishwasher or glasswasher
Quick answer. For most operators: a bar or cafe should go for a quality undercounter glasswasher with built-in softening (add RO if glass presentation matters), and a restaurant kitchen doing real covers should step up to a pass-through hood dishwasher. Match the basket to your ware, confirm your power and drain before you buy, and treat your water. If you're near Tamworth or anywhere in the UK, Lordwell will spec the right machine against your actual peak throughput and water hardness, and stand behind it with proper trade support rather than leaving you to a drop-shipper.
Get warewashing wrong and it shows up everywhere: cloudy glasses on the pass, a bottleneck at the wash-up station on a busy Friday, or a machine that trips the board every third cycle. The right choice comes down to three things: what you're washing, how much of it, and how hard your water is. Nail those and the rest of the spec falls into place quickly.
The questions to ask before you buy
What am I actually washing, and how much per hour?
Glasses only, or plates, pans and gastronorm too? A busy bar might clear 1,500+ glasses a night; a 60-cover bistro turns plates and cutlery. Count your peak-hour throughput, not your daily total. That number decides basket size, cycle speed and whether you need a pass-through or conveyor rather than an undercounter.
How hard is my water?
Hard water is the number one killer of results and machines. In hard-water areas (most of the South and East, parts of the Midlands), you'll get limescale, cloudy glasses and dead elements within months without treatment. Budget for built-in softening or an external ion-exchange softener. For crystal-clear glassware with no polishing, add reverse osmosis (RO).
What power supply do I have at the wash-up point?
Undercounter glasswashers usually run off a standard 13A plug. Larger dishwashers, pass-throughs and anything with a booster heater often need a dedicated 30A hardwired supply or three-phase. Check what's at the wall before you buy; upgrading the supply can cost more than the machine, so confirm with your sparky early.
Does my site have a gravity drain or do I need a drain pump?
If your waste outlet sits above the machine's natural drain height, or the run to the gully is long, you need a built-in drain pump to push water out. Many buyers skip this and end up with standing water and slow cycles. When in doubt, spec the drain pump version; it's a cheap insurance.
How fast do I need each cycle to be?
Cycle time drives real-world throughput. A 2 minute glasswasher cycle is fine for steady trade; a hammered late bar wants 90 seconds or a conveyor. For dishes, look at plates-per-hour or racks-per-hour, not the shortest advertised cycle, which is often the light setting.
Is the machine WRAS-approved and compliant?
WRAS approval means the machine won't contaminate your mains supply via backflow, which UK water regs require for commercial installs. Reputable brands are WRAS-listed as standard. It's a quick thing to confirm, and it keeps you the right side of your water byelaws and your EHO.
The main types, and who each suits
Undercounter glasswasher
Bars, pubs and cafes washing glasses and cups. Fits under a back-bar counter, runs off 13A, 350-500mm baskets. The workhorse of front-of-house.
Undercounter dishwasher
Small to mid-size kitchens turning plates, cutlery and light pans. Larger wash chamber and 500mm baskets; handles more soiling than a glasswasher but still tucks under a counter.
Pass-through (hood) dishwasher
Busy restaurants and gastropubs with a dedicated wash-up area. You load a rack, pull the hood down, wash, and slide it out the other side. Racks-per-hour throughput far beyond an undercounter, with a proper dirty-in/clean-out flow.
Rack conveyor / flight machine
High-volume operations: hotels, banqueting, contract catering, large canteens. Racks feed through continuously for hundreds of covers per hour. Needs space, three-phase, and a serious water supply, so only justified at real scale.
Utensil / potwash machine
Production kitchens and bakeries drowning in pots, pans, mixing bowls and gastronorm. A tall chamber and aggressive wash cycle for the heavy stuff that clogs a standard dishwasher.
What to look for
- Basket size that matches your ware: 350/400/450mm for glasses, 500mm for plates. Getting the right basket avoids double-handling and wasted cycles.
- Built-in water softener or provision for an external one, plus an RO option if you want polish-free, sparkling glassware.
- A drain pump if your waste outlet is high or far; a rinse booster (break tank) if your incoming water isn't consistently hot enough for a proper 82-85C sanitising rinse.
- Realistic throughput figures: baskets or racks per hour at your typical soil level, not just the fastest light-wash number on the spec sheet.
- The correct power supply match: 13A plug versus 30A hardwired versus three-phase, confirmed against what's physically at your wash-up point.
- WRAS approval and a built-in air gap or backflow prevention as standard.
- Double-skinned insulated construction and a decent chemical dosing setup (auto detergent and rinse-aid pumps) for lower running noise, heat and consumable waste.
- Easy-clean internals: removable wash arms, a large filter and a wash tank that flushes down, so daily cleaning is a two-minute job for the KP, not a chore that gets skipped.
Costly mistakes to avoid
- Ignoring water hardness. Skipping softening or RO in a hard-water area gives you cloudy glasses, scaled elements and a machine that dies early. Treat the water from day one; retrofitting after the damage is done costs more.
- Buying on daily volume instead of peak-hour throughput. The machine has to cope with your busiest 60 minutes, not the daily average. Undersize it and you get a wash-up bottleneck exactly when the kitchen is slammed.
- Not checking the power supply and drain before ordering. Discovering you need three-phase or a drain pump after delivery means delays, extra electrician and plumber costs, and sometimes a machine that won't run at all.
- Chasing the cheapest drop-shipped unit with no local support. When a wash arm or element fails mid-service, you want fast UK parts and someone who'll pick up the phone, not a two-week wait from an unknown seller.