For example, commercial equipment is often bullet-proof and long-lived, but it can be louder than you'd want in a home kitchen. Commercial dish washers have no noise insulation, get hot, but can wash dishes so fast they can crack them from the temperature changes.
Commercial ovens have no or minimal heat insulation, so when you fire them up you can really warm up a room fast, and they have to be installed away from flammable materials.
And people need to be honest about it, too - whenever you buy an appliance new, write the purchase date in indelible ink or spray paint on the back of the unit, because I've had appliances I was sure "lasted barely more than the warranty" and then I realized I'd purchased it 15 years ago.
This seems counter intuitive to me. Why would I not want more insulation in an oven that's going to be used a lot more? Seems like the cost of the insulation would be amortized more quickly than in a home kitchen, since a commercial oven is presumably being used a lot more?
Houses aren't built for that.
See https://deqonline.com/blog/post/7-reasons-not-to-use-a-comme... for some example issues that you might not be aware of if you blindly ran in with "commercial better".
If you fully understand them (you worked as a line cook for awhile, etc) and compensate for them, it might be a fine option.
If you need 500,000 BTU.
Insulation is only effective with intermittent use.
Insulation slows heat flow and thus means the hot side rises to closer to the temperature of the heat source and thus there is less energy transfer.
Water heaters are not running 24/7.
The entire point of water heater insulation is that you run them to heat up the water in the tank, then the water sits there at temperature, and when needed it has a fast response time (and also actually provides hot water as the heating loops generally don't have the heating capacity to bring the water up from ambient or sometimes just above freezing to sanitary at the flow rates users ask for).
Hey, if your taps are emitting a stream of hot water 24/7 then you should call a plumber. Expect your water bill to drop massively.
Primarily different regulations. Everyone interacting with a commercial oven is a trained professional getting paid to be there and the space is designed to a certified standard. This means you can focus more on pure performance and less on liability stuff.
And commercial equipment, because it needs to last long, is optimized for maintenance. I imagine insulation makes it harder to access and clean (or fix) the internals of an oven. Not to mention how often you’d have to change the insulation to keep your kitchen up to health standards.
A commercial oven runs all day when it is being used, so it will eventually get hot no matter how much insulation you have unless it's somehow cooled or can send waste heat elsewhere.
One can also actively cool the exterior surface by forcing air through a gap in a double wall oven. Many residential ovens do this.
As far as I know, the actual material difference with residential ovens is that most of them are mean to be installed in cabinets, which severely restricts the amount of heat that can be safely dissipated through the walls.
A well insulated oven cools much more slowly with the door closed, so a control algorithm can’t recover as quickly if it overshoots the set temperature.
Whereas home dishwashers are designed to run all night slowly recirculating water and removing caked-on grime (with more or less success).
