The broken boiler in Decerto’s basement is one of the first major roadblock puzzles you come across in Alone in the Dark, but you can’t actually solve it until a bit later in the game.
In fact, you need to already be finished with the Astronomical Clock sequence before fixing the boiler is even possible in the first place. If you’ve already done that, read on for a full breakdown of how to fix the Boiler in Alone in the Dark.
Where to get the missing Boiler pieces in Alone in the Dark
There are two parts to fixing the Boiler: finding both of the missing Boiler plate pieces and figuring out a way past the steam leak billowing from it. One of the missing pieces comes from a separate area, but the other actually relies on having already fixed the steam leak.
Before you can get either piece, you need to have completed the Astronomical Clock puzzle and returned from the Hateful Mound. As soon as you’re back from the Hateful Mound, you can get started with fixing the Boiler.
The piece behind the Boiler
One of the missing plates is in the corner of the Boiler room itself, just past the steam leak. This means that you need to fix the leak before you can reach it.
As soon as you’re back in the Small Parlor from the Hateful Mound, you can pick up the Paint Chisel key item from Jeremy’s bag. Use the Paint Chisel to remove the wedge underneath the connected door to the Drawing Room.
You will find a few key items in the Drawing Room, but the one that matters for fixing the Boiler is the Cellar Key. Once you’ve grabbed the key from the table, make your way down to the basement, and unlock the metal cellar gate at the back of the Storage Room.
Inside the cellar, you can see the missing Valve Handle from the Boiler in the back left corner, but it is blocked off by a puddle of water exposed to a live wire. This means you need to turn off the power in the basement before you can reach it.
On a wine rack to the right, you can find a Fuse Switch sitting on a shelf. Grab this switch and connect it to the Circuit Box nearby, and then you can shut off the power and reach the Valve Handle.
Head back to the Boiler room with the valve, connect it to the Boiler, and turn the valve to fix the leak. You can now reach the area past the Boiler, where you will find one of the two missing Boiler plate pieces in the back corner.
The piece in Cassandra’s room
The other piece is significantly harder to get, as its locked up in Cassandra’s room by the same kind of astrology lock in Perosi’s room. Unlocking Cassandra’s dresser requires solving a challenging medicine bottle puzzle—we have a full guide available for that, but in this article, I’m going to cut right to the chase.
The combination needed to unlock Cassandra’s dresser is 2-5-7, which is Pisces-Gemini-Leo in the astrology cipher from Perosi’s Journal. Input these three symbols in this order, and Cassandra’s dresser will open, allowing you to reach the second missing Boiler plate piece.
Now that you have both missing pieces, you need to solve a puzzle on the Boiler itself before you can use your Talisman in this socket and progress forward.
