Heating is easy: power in, heat out. Cooling is harder, because heat does not vanish – it has to go somewhere. Every form of cooling in Stationeers is therefore transport: heat is pushed from the room into a pipe network and carried outside from there.
The devices
| Device | acts on | Output | Target value |
|---|---|---|---|
| Wall Heater | room air, heats | 1,000 J per tick, about 2 kW | no |
| Wall Cooler | room air → pipe gas | 1,000 J per tick, about 2 kW | no |
| Air Conditioner | pipe gas only, heats or cools | up to 14 kJ per tick, about 28 kW | yes, in kelvin |
| Pipe Heater (Gas) | pipe gas, heats | 1,000 J per tick | no |
| Pipe Convection Radiator and other radiators | pipe gas ↔ surroundings | depends on temperature difference | no |
| Portable Air Conditioner | room air ↔ liquid canister, portable | up to 2,500 J per tick; without a canister it heats with 250 J | mode Cold/Hot |
Wall heater and wall cooler only work when the room holds more than 6.3 kPa.
How much energy a room needs
The heat of a gas is heat capacity × amount × temperature. A room of four cells at normal pressure contains about 1,330 mol of air. At roughly 20.7 J per mole and kelvin (22 % oxygen, 78 % nitrogen) it needs:
- 1,330 · 20.7 ≈ 27,500 J per kelvin
A 2 kW wall heater therefore raises this room by one kelvin in just under 14 seconds, and a wall cooler lowers it just as fast. Walls, devices and heat losses to the outside come on top – treat the figure as a lower bound.
The wall heater makes a spark every tick. If the room contains fuel and oxidiser of at least 0.00001 mol each, it burns. A gas sensor next to it reports fire through Combustion all the time, even without a fire.
The wall cooler and its pipe network
The wall cooler pulls heat from the room into the gas of its pipe network. That network has to get rid of the heat again, or it keeps getting hotter. There are two ways:
- Radiators outdoors: the pipe network leads outside to radiators that hand the heat to the outside air or radiate it away.
- Air conditioner: it cools the pipe gas and pushes the heat into a third network, which then leads to the radiators.
The wall cooler gets worse the larger the difference between pipe gas and room. A loop just below room temperature works better than an ice-cold one.
The air conditioner
The Air Conditioner has three pipes: input, output and waste. Setting is the target temperature of the output in kelvin, from 3.15 to 1,272.15 K. If the value is above the input temperature, it heats. The heat it takes from the gas ends up in the waste network.
Three values show how well it works: TemperatureDifferentialEfficiency drops with the difference between input and waste, OperationalTemperatureEfficiency with very hot or very cold pipes, PressureEfficiency at low pressure – full only from about 111 kPa on both sides. All three pipes must be connected.
For large temperature steps a cascade pays off: two air conditioners in a row, each with a small step. Important: the Setting of a stage must stay below the temperature of its input loop, otherwise it heats in the wrong direction while starting up.
What the planets demand
| World | Outside temperature per world data | Consequence |
|---|---|---|
| Mars | about 3 to 10 °C at noon, about −52 to −47 °C at night | heat at night, insulate outdoor lines |
| Europa | −139 to −149 °C | heat permanently, liquids freeze outside |
| Venus | 464 °C, day and night | only cool; radiators only cool even hotter loops |
| Vulcan | not below about 127 °C at night, far above at noon | never heat, keep the waste-heat loop above 127 °C |
| Moon, Mimas | vacuum | no convection, radiation only |
In vacuum radiators only work through radiation. There the Medium Radiator with a radiation value of 30 is the right choice; on worlds with an atmosphere the Medium Convection Radiator with convection 9.38.
IC10: thermostat with heater and cooler
This program keeps a room between 18 and 26 °C. It heats below 18 °C up to 20 °C and cools above 26 °C down to 24 °C. Thanks to the gap in between, heater and cooler never work against each other.
# Thermostat: wall heater and wall cooler
define SENSOR -1252983604 # Gas Sensor (StructureGasSensor)
define HEATER 24258244 # Wall Heater (StructureWallHeater)
define COOLER -739292323 # Wall Cooler (StructureWallCooler)
define NSENSOR HASH("Living Sensor")
define NHEATER HASH("Living Heater")
define NCOOLER HASH("Living Cooler")
define CELSIUSOFFSET 273.15 # 0 C in kelvin
define HEATON 18 # C, heat below
define HEATOFF 20 # C, stop heating above
define COOLON 26 # C, cool above
define COOLOFF 24 # C, stop cooling below
alias temp r0
alias heat r1
alias cool r2
alias tmp r3
start:
yield
lbn temp SENSOR NSENSOR Temperature 0
bnan temp start # no sensor with this name
sub temp temp CELSIUSOFFSET # kelvin to Celsius
# --- 1. Heater with hysteresis ---
slt tmp temp HEATON
select heat tmp 1 heat
sgt tmp temp HEATOFF
select heat tmp 0 heat
# --- 2. Cooler with hysteresis ---
sgt tmp temp COOLON
select cool tmp 1 cool
slt tmp temp COOLOFF
select cool tmp 0 cool
sbn HEATER NHEATER On heat
sbn COOLER NCOOLER On cool
j startYou only change the thresholds in the define lines. Several heaters in the same room simply get the same name – one sbn switches them all. The hysteresis pattern is explained in the academy: hysteresis.
Common mistakes
- Cooler without a way for the heat: the wall cooler's pipe network heats up until it hardly manages anything.
- Radiator on the wrong loop: a radiator on a loop colder than its surroundings warms that loop.
- Air conditioner with only two pipes: it does not work, and there is no error message.
- Fire alarm next to the wall heater: reports fire constantly, see above.
Where next
- Heat exchangers and heat transport: pipe to pipe, gas to liquid – moving heat between loops
- Evaporating, condensing, freezing: using phases on purpose – cooling with evaporation and condensation
- Atmosphere and pressure – why heat raises pressure
- Planet data: Planets, calculator: Planet data sheet