The Sinking City 2 Guide | How to Solve the Ventilation System Puzzle

The Ventilation System Puzzle in The Sinking City 2 requires you to manipulate three buttons and a lever to align four gauges with their marked positions. Solving the puzzle activates the ventilation system, clears the poisonous gas from Devil’s Reef Hotel, and opens the way forward.

The puzzle can be found in the Generator Room beneath Devil’s Reef Hotel during Chapter 2: The Wake-Up Call. Unlike some of the earlier puzzles in The Sinking City 2, the solution isn't immediately obvious, as each button affects multiple gauges at once.

If you're having trouble figuring out the correct sequence, you don't need to experiment with every possible combination. Follow the button order below to solve the Ventilation System Puzzle in just a few steps.

Where to Find the Ventilation System

The Ventilation System Puzzle takes place in the Generator Room beneath Devil’s Reef Hotel during Chapter 2: The Wake-Up Call.

Before reaching the Generator Room, you need to progress through the hotel and complete the Lorelei Lock sequence. Once you've collected the required keys and opened the lock, continue through the basement.

Follow the route toward the Generator Room while avoiding the poisonous growths. You'll eventually find the Ventilation Machine with four gauges and three buttons.

How the Ventilation System Works

The objective is to move all four gauges into their green zones.

The three buttons control different gauges:

• Button 1: Moves the first two gauges.
• Button 2: Moves the middle gauges.
• Button 3: Moves the fourth gauge.
• Lever: Reverses the direction of the gauges.

The trick is to use the buttons in the correct order rather than trying to manually adjust each gauge individually.

Ventilation System Puzzle Solution

If the machine is still in its default starting position, use the following sequence:

• Press Button 1 twice.
• Press Button 2 four times.
• Press Button 3 twice.
• Pull the lever.
• Press Button 1 once.

The correct Ventilation System Puzzle sequence is 1 → 1 → 2 → 2 → 2 → 2 → 3 → 3 → Lever → 1.

Once you've completed the sequence, all four gauges should line up with their green markers. The ventilation system will activate and begin clearing the poisonous gas.

What to Do After Solving the Ventilation Puzzle

Once the Ventilation System is active, the poisonous gas blocking the next route is removed. Before leaving the Generator Room, make sure to pick up the Minuteman submachine gun on the table beside the machine

Return to the area near the Lorelei Lock and enter the previously inaccessible route. Continue through the basement until you reach the lift leading toward Lorelei.

The ventilation puzzle marks the end of the main exploration portion of Devil’s Reef Hotel and leads into the Lorelei rescue sequence.

FAQ

Q. What is the Ventilation System Puzzle solution?

A. Press Button 1 twice, Button 2 four times, Button 3 twice, pull the lever, then Button 1 once.

Q. Where is the Ventilation System?

A. The machine is located in the Generator Room in the basement of Devil’s Reef Hotel.

Q. What does the Ventilation System Puzzle do?

A. Solving it clears the poisonous gas blocking the next section of Devil’s Reef Hotel.

What should I collect before leaving?

A. Pick up the Minuteman submachine gun beside the ventilation machine before continuing.

Q. What happens after the puzzle?

A. You can proceed through the newly cleared route and continue the Lorelei rescue sequence.