In every commercial kitchen there are at least three kinds of large-scale equipment: cooking, refrigeration, and ware washing. Although we already have most of the equipment in all three categories, we went out today and bought a dish washer and a refrigerator.
Hold it, you say, I can see that there's never enough refrigeration in a restaurant (and I say, I taught you well), but don't you already have a dishwasher?!
Oh you clever readers you, who read every word I write ... grrr!!! Yes, we already have a dishwasher, but when we bought it we were young and stupid (today we're old and stupid), and didn't realize that albeit the dishwasher was 3-phase (in its previous life) it had been converted to single phase, in particular the 3-phase motor had been replaced with a single phase motor. The amount of money it would take to convert it back to 3-phase (by replacing the motor) is prohibitive, in fact you can by a used dishwasher for just a few bucks more.
Aside from the 3-phase issue, our present dishwasher would have required a booster heater, and, let's face it, it's more than 30 years old! Our new dishwasher doesn't have any of these problems, it's 3-phase, it has a built-in booster heater, and it is only a few years old.