Inaccessible in Claire Redfield’s campaign, the Boiler Room is only available for Leon’s campaign (either scenario). However, finding this location is a bit of a headache. The location is clearly visible on the in-game map, it’s located on the first floor of the Police Station, behind the portion where the Helicopter crashed. So, it’s a bit difficult to understand how to get pass the helicopter debris.
Surprisingly (and shockingly) enough, reaching the Boiler Room is an extremely easy task. Now, before we tell you how you can get to the Boiler Room, there is something you need to keep in mind. You have to finish the Three Medallion quest, go through the Parking Lot and make your way back to the Police Station. Once you are back, go to the Art Room on first floor of the Police Station. Now exit the Art Room and take a left and you will come across a locked Shutter. Use the Crank (which you must have procured from the table in the Jail area while you were in the Parking Lot, if not go back and procure it). Once the Shutter is open, go upstairs, you will now reach the Roof area. Now drop down using the ladder and you will be on the outside area from where the Helicopter crashed.
Now you need to extinguish the fire; fortunately, there is a device near the ladder that does exactly that. However, don’t use that for now. Go down the stairs and you will come across another device, switch it accordingly. Don’t go back yet! Near the device there is Save room (which is the Boiler Room!), go inside and just besides the typewriter there is a white board where you will find the Club key.
Now go back to the device near the ladder, and now switch it accordingly. Water will start pouring over the Helicopter and you can proceed ahead through the door on the left side of the crashed helicopter.
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