I have a question about the fire protection system. Is it true that it only works with the laser? It would be great if it also worked during the actual printing process, as that would make it a bit safer. Could you explain how it works exactly?
It is my understanding that the fire extinguisher is only active when the laser module is attached.
On the store page, there’s a video under the Installation Guide heading that shows the process in action but essentially:
- You install the extinguisher with a tube that routes through the back of the printer and into a nozzle in the chamber
- If the camera or any of the flame sensors detect a fire, an alarm is sounded and a countdown starts on the printer screen.
- Before the countdown reaches zero, you can either cancel the alarm (if it was a false alarm or small enough to not be a concern) or trigger the extinguisher immediately.
- If the countdown reaches zero, the extinguisher will fill the chamber with CO2
There’s a backup, manual trigger that can be used in case of a power outage.
Lasering is an inherently combustive process - you’re using high heat to remove material, and the material can be set on fire by the heat. The material in a perfectly working laser cutter could catch on fire at any time, with the probability going up if the user makes mistakes with laser power and speed.
In contrast to that, FDM printing is not combustive in any way - temperatures are far below the threshold for spontaneous combustion of the plastics. There’s no mistake a user could make that would change that constraint. The only way you can have a fire with a FDM machine is if the machine itself catches fire, which does happen sometimes (eh-hem, A1), but not enough to be worth adding the costs to detect and put out such a fire (assuming the power supply isn’t what’s caught fire, which will disable the circuitry).
I would bet your odds of getting struck by lightning are better than your odds of having your printer catch fire while printing. 
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You know, the A1 series has shown that printers can actually catch fire even during printing. There’s also no shortage of information about such fires on the internet. In general, I bought this system, but I’m still not sure whether it is active during printing (I mean the auto mode). The system menu is only available when the laser module is installed, so I assume it probably doesn’t work while printing.
It would be nice to have some additional protection during printing. Sometimes prints take more than a dozen hours, and people still need to sleep. It seems to me that extending this system to work during printing could probably be done at the software level, so it would be great if Bambu considered something like that.
Yes that is true. I made the mistake but was able to return.
The H2 fire suppression system only protects the chamber, and that only when material is intentionally being burned by the laser. It does not detect or extinguish the type of overheating faults experienced by the A1, which were the cords and electronic components. Fires are much more common in microwave and toaster ovens, but I don’t know of any with fire suppression.