Thermo Aquatuner

The Thermo Aquatuner is a liquid-cooling building that removes heat from any liquid piped through it and transfers that heat into itself and the surrounding environment. It does not create heat on its own, so in principle it is heat-neutral: if the building’s own heat is removed as quickly as it is generated by absorbed coolant heat, the Aquatuner can keep running without drifting upward in temperature. It is one of the most important tools for active cooling, and it is also the only building that can reliably produce liquid oxygen and liquid hydrogen because it has no minimum output temperature.

Each packet of liquid passing through the Thermo Aquatuner loses a fixed 14 °C, regardless of the liquid’s specific heat capacity or packet size. Because the amount of heat removed is tied to the coolant’s specific heat and packet mass, high-shc liquids are the most efficient choices. Water, Polluted Water, and Super Coolant are common coolants for this reason, with Super Coolant offering the greatest heat capacity. The building draws 1.2 kW while operating, even if it is no longer able to remove any more heat from a packet that has already reached the 1 K lower limit. Its thermal conductivity does not affect the cooling effect itself; it only matters when the coolant exchanges heat with the environment.

The building’s own self-heating is the main constraint on long-term use. The more heat it pulls from coolant, the hotter it becomes, and if that heat is not removed it will overheat and take damage. For that reason, the choice of construction material is critical. Steel is the reliable early- and mid-game option, while Thermium is the best late-game material. Using these materials greatly improves the Aquatuner’s performance, but also increases the need for precise temperature control because they can move much larger amounts of heat.

A Thermo Sensor is very much recommended, and in practice is required for efficient control. Placing the sensor near the Aquatuner lets it measure either the building’s temperature or the temperature of the fluid around it, depending on the setup. This is especially important when the Aquatuner is made of Steel or Thermium, since the faster heat transfer makes the system respond quickly enough to regulate temperatures reliably.

There are also several important coolant and pipe interaction limits:

• Polluted Water is often preferred over Water because its freezing point is much lower, giving more safety margin against burst pipes.
• The Aquatuner does not respect freezing temperatures. If the coolant is cooled below its freezing point, it will damage the output pipe.
• If the pipe network stops while a coolant that can freeze is inside the Aquatuner, the liquid can become trapped in the building and may leak from it.
• Nuclear Waste can move very large amounts of heat, but it must not be allowed to drop below its freezing point.
• Since buildings have only one-fifth of the specific heat capacity of the material they are made from, the heat contained in melted output can be much greater than the heat removed from the coolant. This makes the Aquatuner useful for metal-melting tricks, especially with Steel.

In vacuum, an Aquatuner continuously cooling a full pipe of Water or Polluted Water can melt before overheating damage destroys it, so auto-repair is often disabled in such setups to avoid wasting metal. This makes the building useful not only for cooling loops, but also for specialized heat-management and industrial tricks where intentional overheat behavior is part of the design.