In the first chapter of Signalis, you’ll need to find several keys to open an intricate door that uses a credit card slot-like unlocking mechanism. One of those keys, the fire key, is very tricky, as it involves solving a puzzle that mostly demands brute force. But with our fire key guide, you can apply a more gentle hand. We’ve done the hard part already. Here’s how to get the fire key in Signalis.

Signalis fire key location

As one of the six elemental keys you need to open the locked door on the second floor of the space vessel, the fire key is a main quest item you’ll need in order to beat the game. Each key in this area has a different solution, but the fire key is one of the trickiest of them because it’s locked away behind a classically obtuse puzzle.

To get the fire key, you’ll want to head into the room labeled Incinerator on the vessel’s third floor, the Medical Ward, where you’ll find the gas valve puzzle. In our playthrough, we didn’t find any documents hinting at the solution to this puzzle like we did with others, such as the Signalis safe codes, but we were able to make it through this section using trial-and-error.

The furnace linked to the gas valves has three dials: carbon dioxide, dioxide, and one just labeled “gas.” The goal here is to tweak the dials until the black line shown on the display fully traces over the static red line on the same display. Each time you pull the lever on the right, the black line will slowly draw down the display, but unless you’ve done it correctly, the black line won’t fully trace the red one. Basically, fidgeting with the dials is all you need to do here, and you’ll know whether a dial is right or wrong thanks to the left side of the interface, where the machine will tell you whether any dial is too high, too low, or just right.

You can tweak these on your own if you’d like to now that you know how it works, but we’ve also included an image below that reveals exactly where you’ll want to turn the dials–assuming answers are the same across playthroughs. If you match your dials in-game to the positions you see below and pull the lever, you’ll see the furnace will then open, revealing your prize: the much-needed fire key.

For more on the retro-inspired horror game, check out our Signalis review.