Main Boiler

The Main Boiler is a heat-regulating system in Sector 3 of the Biologic Space Laboratories research station. During the events of Metroid Fusion, Samus Aran discovered the X Parasites' plot to overheat the cooling system and thus destroy the station, destroying themselves but giving the X on SR388 a chance to survive. Initially, it was believed that the SA-X, Samus' X-mimic, was responsible, but it was later discovered to be a human scientist infected by the X.
The room shows signs of destruction by the inhabiting X mimics. A ladder is chewed to ruins while some platforms contain small gaps in-between sections, causing Samus to fall if she is not careful with her navigation. Before the emergency in Sector 3, the room's background is red with color and with a noticable heat wave effect, with the boiler machines producing lines of glowing red/orange on itself and its pipelines. This is never seen clearly normally (only via debug or sequence breaking); when Samus first enters the room during the Countdown, the room gains an additional flashing alarm light, making the room's background hard to notice at the time. The only other time the background can be seen clearly is after the Main Boiler has cooled down, which displays a different background: the large generator-like pillar is now purple, the boilers and its pipes do not produce lines of glowing red/orange on itself, and the heatwave effect is gone, all signifying the Main Boiler's cooling efforts.
==Connecting rooms==
*Main Boiler Control room (via Gray Hatch)
*Sector 3 ultra-heated access hall (via Gray Hatch)
==Inhabitants==
*1 Gadora
*4 Sidehoppers (+ 2 more additional Sidehoppers will spawn if the X parasites are not absorbed in time). 
==Trivia==
*In the original prototype builds of Metroid Fusion, the walls and overall background color for this room were orange before the "Emergency in Sector 3" event (exactly the same color scheme as in the final). However after the Countdown and boss fight, the room changed into a Red color scheme not seen anywhere else. In the Final, the room is always orange color schemed the entire time.
**Why this change was made is unclear, it may have been intended to show that the Boiler Room has cooled off after the event. But since it is almost normally impossible to see the pre-countdown color scheme and there is very little reason to visit this room after obtaining the Wide Beam (as there are no other Items or upgrades in this room or along this route), it was probably deemed unnecessary to have this aesthetic change.https://tcrf.net/Proto:Metroid_Fusion/0911_Prototype#Room_Palette_Changes
**The purple pillar seen in the prototype red colored room was retained in the final's orange color scheme however, being shown in the post-cooldown version of the room (as stated above).
==Gallery==
MF Main Boiler.png|The Main Boiler after Samus restores the cooling system.
Main Boiler Room (Prototype).png|The Red hued Main Boiler Room seen in the prototype (post Countdown).
es:Caldera Principal
ru:Главный нагреватель
Category:Rooms
Category:Sector 3