Alone In The Dark - Chapter 2 Boiler Plate Puzzle Guide

Late into Chapter 2 of Alone in the Dark you will be tasked with solving the plate puzzle on the boiler in the basement. This comes after returning from a mysterious oil field. In order to solve this puzzle, you will first need to gather the missing pieces of the puzzle, one located beyond the broken boiler itself and the other is one of the patient's rooms. Here's how to solve the puzzle.

Cassandra's Room Lock Box

The first piece is located inside a box in Cassandra's Room, found on the second floor adjacent to the Sitting Room. The Sitting Room key is given to you alongside the Palette Knife when you return to Decerto from the oil rig. Enter the area and head into Cassandra's Room and you will find a locked box with another combo lock showing astrology signs. There is also a small puzzle where you can order four medicine bottles, but two are missing. One is in that same room on the desk, with the other locked in a medicine box in Lottie's Room. There is a note in here stating that the key can be found in the Grand Parlor.

If you want to skip the search for medicine bottles, just scroll down to the lock solution below.

Head to the second floor via the Servant's Stairs, where you can open a door to a hallway next to the Mezzanine. Circle around to the staircase on the north side and head down to the Grand Parlor. On the piano in the center of the room is the key to the Medicine Box. Take the key and head to Lottie's Room to get the second medicine bottle.

Take that back to Cassandra's Room and solve the row of medicine bottles by rotating placing them so the rot makes one continuous line, as shown in the image above. This reveals the numbers 2, 5, 7, which translates to Pisces, Gemini, Leo on the astrology wheel note. Put that combination in, as shown below.

Boiler Room Plate Piece

Next up is the piece located in the Boiler Room, which you will need to disable the broken boiler to reach. A note found in the boiler room earlier in the game tells you that the valve can be found in the Cellar, behind a locked gate. The key can be found in the Drawing Room on the first floor, which you can use the Palette Knife to access. With the key in hand head down to the Cellar and enter the locked area.

The Valve is located at the back of this area, but an electric wire blocks the path. There is a breaker box in the corner, with the missing breaker for it on the wine rack next to it. Put the breaker in the box and it will kill the power to the basement, letting you retrieve the valve. Now head back to the Boiler Room, be warned there is an enemy in the basement hallway now. Turn off the boiler and head into the back room, where the second plate piece is located.

Boiler Plate Puzzle

With both plate pieces retrieved, add them to the puzzle and then solve it. You need to swap pieces and rotate them to create an image of a farm and chapel, as shown above.

Once that is solved, the boiler will kick back on, showing three numbers on the pressure gauges on the side. The numbers, in order from biggest to smallest gauge are 9, 7, 5. Enter them in that order on the Talisman on the boiler, which will show you images of the Cellar. Head out of the Boiler Room back towards the Cellar to discover the new area you can now access.