This was really cool! I struggled a bit at the very beginning to understand exactly what I was supposed to be doing. Although I think overall the game does a good job of having everything kind of explain itself, it took me a bit to realize how the fires related to the open pipes (Once I got that everything was pretty intuitive and the puzzles were fun to solve).
Maybe having a really easy fire out in the open right in the beginning that spawned one of the pipe-valves would have helped with this, so that it's very clear what the player needs to do and why? Or maybe I'm just a bit unobservant lol.
Overall, great job. I really enjoyed it!