The boilers on an espresso machine can be exposed to pump pressure, since heat exchangers can burst. I don't know what this terms of boiler design, but Expobar uses the same off-the-shelf vessel for their steam and 9 bar brew boilers inside the Brewtus, so my guess is that many espresso boilers are designed to work with higher pump pressures.

But all that aside, the safety stat on espresso boilers is set to 2 bar -- all the companies that insure you, your building, the machine, its manufacturers and sellers are going to walk away from any accident if you defeat it in your pressure test. My guess is you'd have a hard time finding even a personal injury lawyer to take on that case.

personal injury lawyer wrote:Yes, your honor, when my client blew up the boiler he knew exactly the risks involved and how to defeat the safety equipment. We are pleading Internet Forum Derangement Syndrome, IFDS a condition where the afflicted person has such an excess of information that he loses his innate caution and takes insane risks

another_jim wrote:"personal injury lawyer wrote:Yes, your honor, when my client blew up the boiler he knew exactly the risks involved and how to defeat the safety equipment. We are pleading Internet Forum Derangement Syndrome, IFDS a condition where the afflicted person has such an excess of information that he loses his innate caution and takes insane risks

Small world - you know my lawyer..