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Barotrauma Wiki
Barotrauma Wiki
Category Machines
Power Consumption 300 kW
Max Pump Speed 600
Small Pump
Pump small.png
Category Machines
Power Consumption 60 kW
Max Pump Speed 100

The pump is an installation found in Barotrauma. It is used to pump water out of or into the submarine.


The pump's primary function is to pump water into and out of its given area. By using the pump, a small menu will appear in which the player is able to manually activate/disable the Pump and modify both the direction the water is being pumped into and the speed at which it is being pumped. For instance, setting the pump slider towards IN will cause water to flood into the Submarine, while dragging the slider towards OUT will pump water out of the area. The slider can be adjusted to regulate the Speed at which the Pump interacts with Water.

In addition to the obvious use for the pumps, to pump out water when a flood occurs, they can also be used to control the vertical movement of the sub, or to extinguish fires.

As of the Steam Release, the normal Pump is often used as part of the Ballast, and linked with the Navigation Terminal to automate the process, while the Small Pumps are used in Airlocks and spread throughout the Submarine, and may be linked with a Water Detector to automate its use, or require manual interaction.


Ballast pumps are pumps wired to achieve a certain water level in the room they are in, thereby controlling the buoyancy of the submarine, which determines its vertical acceleration.

This is usually done by wiring the pump's set_targetlevel input to the Navigation Terminal's velocity_y_out output. The target level accepts decimal values from -100 to 100, for pumping the room to a water level of 0 and 100 respectively. When a velocity is set, the pumps direction is automatically set and it will begin lowering or raising the water level to the appropriate level.

This and a power input are all that is required for a ballast pump to function correctly.


Bilge pumps are pumps wired to remove water from the sub. The usual configuration is for water to flow through ducts to the bottom of the sub, where water detectors trigger the bilge pumps to remove it.

A simple circuit would have a water detector passing a signal of 1 to the set_state input of the pump, and also to a signal component, which will send an output of -100 and a false output of 0 to for a target signal of 1 to the set_speed input of the pump. In this way, the pump is only active and deteriorating when water is in the room, and will pump at maximum speed until the room is empty.


Pump gui.png

Connection Panel[]

Connection panel for Pumps
Connection Port.png power_in
Connection Port.png toggle_state
Connection Port.png set_state
Connection Port.png set_speed
Connection Port.png set_targetlevel
Connecting a power source to this input will supply the pump with power.
Turns the pump on/off whenever a signal is received.
Turns the pump off when a signal "0" is received, and activates it when any other signal is received.
Sets the speed of the pump to the received value. The value is clamped between -100.0 and 100.0.
Sets the target water level in the room to the received value. -100 means that the pump will try to empty the room completely, 0 means that it will try to fill the room half way and 100.0 means that it will try to fill the entire room with water. The value is clamped between 0.0 and 100.0.