[barnabee]

Dishwashers in commercial kitchens are rapid, much less than 10 mins. I have always wondered why, exactly, we can't have that at home. A dishwasher so fast that it's done while you're still clearing up from dinner and you can put stuff away immediately would be fantastic and is clearly absolutely possible.

[masklinn]

> I have always wondered why, exactly, we can't have that at home.

You can. It’s just way less efficient, way noisier, and way more expensive. A Hobart conveyor dishwasher has a cycle time south of 3mn (and throughput of 3 racks/mn, with conveyor speeds reaching 6ft/mn). But it’d probably take most of your kitchen and blow up your electric panel (they need an exclusive 208V 3-phase, and if you plonk for the booster heater that’s a separate supply of the same).

It might also be less reliable, as it won’t really have the occasion to get up to spec (like only running a car for a few miles at a time and never getting it to temp before stopping).

Home dishwashers are designed to work with essentially random inputs (with acceptable results), work very efficiently, and last for long at relatively middling loads / cycling. The middle one is an especially big factor, modern home dishwashers use very little water and less power, so e.g. they’ll often cycle between top and bottom racks rather than have the water and power to run both.

[_trampeltier]

Industrial dishwasher use much stronger detergent. So at home often have paintings, drawings or golden things on the dishes. With an industrial dishwasher such things would be a short joy.

Also you need much more electricity, because you need to make a lot of hot water in a very short time.

[masklinn]

I think just the thermal cycling of an industrial dishwasher would damage consumer dishes in just a few cycles, if they even survive the first.

[MereInterest]

To my understanding, restaurant dishwashers also assume that foods residue has already been removed, and are primarily to sanitize the surface with high temperatures. Residential dishwashers, by contrast, start by prewashing anything that is immediately removable, main wash to slowly break down anything stuck on, and only then go to the high temperature sanitization step.

Commercial dishwashers also assume they’re installed in a location with lots of airflow and ventilation, so they can just dump steam into the room and trust the HVAC to remove it. A residential dishwasher may instead have a cool-down step during which the steam condenses, which avoids releasing steam into the kitchen.

[masklinn]

Hobart’s prospectus don’t necessarily agree (there’s a fair bit on managing residue), but it’s definitely on the lighter side of dirty, and not for heavily soiled stuff like pots and pans.

[Arnt]

I asked at the shop where I bought our dishwasher. They have a different precondition. Home dishwashers deliver clean results from messier inputs. Dried fat on the plates from yesterday's breakfast. The fast dishwashers have to be run within minutes, and you have to be more careful about how much dreck there is on the plates.

I too would like to have a faster dishwasher. When we cook while the dishwasher is running, a queue builds up on the working spaces, and there's only so much space. It's a problem.

More pertinently, this isn't the first article I've read titled "nobody wants [x] — [conclusion]" that was confident and wrong about the starting premise. Is this the kind of thing women call mansplaining? Sounds like it.

[tomn]

From my limited understanding:

- the mechanism is large compared to the capacity

- they are noisy

- they require lots of power

- they need to be pre-heated (so only make sense if you're running more than one load)

- they require more chemicals for the same load sizes

People have done it, but it's not that practical for most people, especially if you're only washing up for one or two people.

[actionfromafar]

And you ideally would have one of the large sinks and huge water hose to pre and post rinse the dishes if need be. From having used one of the commercial kitchen dishwashers, I think the amount of work is actually more than for a home appliance dishwasher, but the benefit is speed. There is no waiting around.

(The chemicals are probably also dangerous to the intestines, as seen on HN.)

[justsomehnguy]

> we can't have that at home

Home dishwashers are:

delicate: do you want to replace all your dishware with horeca dishware?

quiet: nobody cares how loud commercials are , they aren't in the customers ear shot

energy-saving: commercial require 30A instead of 15A of home ones

aren't fast: how much it can clean for a 120 seconds?

    SPECIFICATIONS
    Capacities
    Cycle Time (seconds)  . . . . Light 120 / Normal 146 / Heavy 275
    Racks per Hour  . . . . . . . Light 30 / Normal 24 / Heavy 13
    Tank Capacity – Gallons . . . 2.9
    
    Motor Horsepower
    Wash  . . . . . . . . . . . 0.85
    Rinse . . . . . . . . . . . 0.19
    
    Water Consumption
    U.S. Gallons per Rack (maximum use) . . . . . . . . . . 0.62
    U.S. Gallons per Hour (maximum use) . . . . . . . . . . 14.88
    Peak Drain Flow – U.S. Gallons (gallons per minute) . . 4.0
    
    Temperatures °F
    Wash . . . . . . . . . . . . . . . . . . . . . . .  150
    Rinse . . . . . . . . . . . . . . . . . . . . . . . 180
    Incoming Water Temperature (minimum recommended) . .55-80

https://www.hobartcorp.com/products/commercial-dishwashers/u...

https://cdn2.webdamdb.com/md_Ay2GESwcF7v9.jpg.pdf?1566411389

[beerandt]

You want a "Professional" dishwasher, not a "Commercial" one.

Commercial are for high throughput. Professional are for special needs, like labware or medical equipment, and have customizable cycles.

Typical cycles of 25-30 mins, and some with cycles as short as 3 mins.

But they're still about 5x the cost of a basic residential model, even if cheaper than commercial types.

[actionfromafar]

It is possible, but I think the market is tiny.