Blue Prince: Pump Room Guide
Image Credits: Dogubomb, Blue Prince
If you’ve made it to the Pump Room in Blue Prince and feel like you're trapped in a water jug puzzle from a mid-90s action movie, you’re not far off. This room controls the water flow across several parts of Mt. Holly, and it’s also the only way to drain or fill major water-based areas like the Fountain and Reservoir.
Here’s how the pump room works.
How to Unlock the Pump Room
You’ll need to first draft a Pool. Once you place it, the Pump Room becomes a possible draft for that same day—along with the Sauna and Locker Room. Without a Pool in the manor, the Pump Room will never show up.
What’s Inside the Pump Room
Here’s a rundown of what you’ll find inside:
Control Panel: Six buttons for six different water sources—Fountain, Reservoir, Aquarium, Kitchen, Greenhouse, and Pool. Each has a meter above it showing how full or empty that source is.
Pumps (1–4): These let you move water to or from the selected water source.
Levers on Pumps:
Pull down = Fill the selected room.
Push up = Drain water into the tanks.
Leave centered = No change.
Tanks: You’ve got Tank 1 and Tank 2, plus a third reserve tank that only works if you activate the Boiler Room.
Tank Switch: This little switch lets you decide whether Pump 2 drains into Tank 1 or Tank 2.
You’ll also notice a wall of six pipes matching the six buttons on the panel. They’re ordered left to right the same way as the panel: Fountain, Reservoir, Aquarium, Kitchen, Greenhouse, and Pool.
How to Move Water Around
Pick your target by pressing a button on the control panel (like Fountain).
Follow the pipe from that button to see which pump controls it.
Use the lever on that pump to either drain or fill.
Watch the blue bars on the panel rise or fall as water moves.
Read More: Blue Prince All Rooms Guide
Important Tips
The system acts like a logic puzzle: you can’t drain a room if there’s no space in the tanks, and you can’t fill a room if there’s no water in the tanks.
Want to drain the Fountain? Drain into your tanks first, then send the water to rooms like the Greenhouse or Kitchen to use it up.
If you activate the Boiler Room, you’ll unlock use of the reserve tank, giving you more water storage options.
What Makes the Pump Room Important
Using the Pump Room isn’t just about draining puddles. It helps you unlock hidden paths (like the stairs under the Fountain), gain access to areas like the Reservoir, and occasionally solve specific puzzles tied to the Aquarium or Kitchen.
Water states carry over between runs too. If you drain something today, it’ll stay drained tomorrow unless you go back and change it.
Final Blurb
The Pump Room is one of those places in Blue Prince that feels way too complicated until it clicks—and then it becomes one of the most powerful tools you have. It’s not flashy. There are no gems or secret doors (unless you count the ones it leads to). But if you’re trying to explore the full house? You’ll need to master the pumps. Just don’t forget which lever you flipped last.
Recommended | View all Blue Prince
