RimWorld Life Support Unit: 3,200 W, Heat, and Oxygen

What the life support unit does

Its in-game description only says it is "connected to the orbital platform's larger life support network" and "keeps rooms heated and pressurized." That's accurate as far as it goes. It leaves out the power, which is the part most players care about. One unit handles three things at once:

The three jobs are independent. Heat and oxygen don't need the unit to be on a power grid, and power doesn't care whether the room is sealed. Each unit also has 35 HP, a market value of 200 and a mass of 3. It hangs on a wall, and pawns can walk over its tile.

Power: 3,200 W that never stops

A life support unit is a power plant with no fuel tank, no breakdown chance and no on/off switch. It produces 3,200 W from the moment the platform exists. For scale, that's almost as much as a geothermal generator (3,600 W) and more than three chemfuel generators (1,000 W each). One player counted 22 units on a single platform, which works out to 70,400 W. Your platform will have more or fewer depending on how its rooms rolled.

How to get it onto your grid

The unit doesn't hand out power by itself. It carries power the way a conduit does, so it only joins a grid through something touching its tile. The tile is the floor tile directly in front of the wall box, not the wall.

1. Find the floor tile in front of the box.
2. Run a power conduit to a floor tile directly beside it, sharing an edge: left, right or the tile in front.
3. Open the power overlay. The unit's 3,200 W now counts toward that grid.

The fortified platform walls carry no power, so a conduit on the far side of the wall does nothing. Two units on opposite sides of the same wall need their own conduits.

Batteries and solar flares

The output never changes, so you only need batteries to cover moments when your draw is above what the units make. During a solar flare, the grid stops feeding your machines like it does anywhere else. The unit's heat and oxygen keep working through the flare, because they never used the grid. For flare prep, see solar flare survival and battery planning.

Heat: a 20°C heater you can't adjust

Each unit adds 30 heat per second to its room until the room reaches 20°C. A standard heater adds 21 at 175 W, so one unit is worth about 1.4 heaters, for free. Before losses to the outside, that's about 0.3°C per second in a 100-tile room and 0.15°C per second in a 200-tile room. It behaves differently from a heater in a few ways:

• The target is fixed at 20°C. There is no setting to make a room warmer.
• It never cools. Above 20°C it sits idle, so it won't fight your coolers or help them.
• The room has to be enclosed. Once a quarter or more of the roof is open, the unit stops heating entirely.

Space outside is a constant −75°C. Platform rooms generate at 20°C, but every unroofed tile, door to space and wall gap leaks that heat away. If colonists are still cold in a big hall or a leaky room, add a heater from your ship. One unit can't keep up with every leak.

Oxygen: sealed rooms only

On a vacuum map, a unit lowers its room's vacuum by 5 percentage points per second per 100 tiles. Smaller rooms fill faster, bigger rooms slower. An oxygen pump does 1 point, so one unit equals five pumps, with no power draw.

Colonists without vacsuits take vacuum damage only while the room is at 50% vacuum or more, so a room is safe well before it reaches 0%.

Units and pumps work in steps about every four seconds, so the exact time depends on where in that cycle the room was sealed. Several sources in one room add together.

The air only flows when the room is sealed. If any tile of the room has no roof, has a vacuum floor or touches the map edge, the room counts as open to space. It stays at 100% vacuum no matter how many units are inside. On a planet's surface there is no vacuum to remove, so the oxygen part does nothing there.

Doors are different. An open door to a vacuum room doesn't pin the room at 100%. It trades air every few seconds, so the units keep refilling while the door leaks it away, and a big leak can outpace them. Use airlocks or vac barriers. The oxygen pump guide covers airlock layouts and pump counts.

Life support room calculator

Enter the room size from the room stats, its current vacuum, and what is filling it. You'll see when it drops below the 50% damage line, when it reaches 0%, how much power the units add, and how hard they push the temperature up.

Times are for 1× speed with every door closed. The heat figure ignores losses to the −75°C outside.

Where to find life support units

Life support units only appear on orbital platform maps. While a platform is generated, each room gets one chance to place a unit on a wall, so you'll find up to one per room. The total depends on how many rooms the layout rolled. Players have reported 21 and 22 on large platforms.

Older guides that tell you to tour surface garrisons for units date from Odyssey's first two weeks. Use orbital platforms instead.

Orbital maps are dangerous. Bring vacsuits and helmets, and read the vacuum resistance guide before you land.

Life support not working? Check these

You can't build a new one

In vanilla 1.6 there is no recipe, no research and no build button. The unit can't be claimed, repaired, deconstructed or uninstalled, so every unit you lose is gone for good.

With 35 HP, a stray grenade or a firefight next to the wall can kill one, so fight raiders and drones away from your best units. The wall itself is tough (fortified platform walls have 7,500 HP and can't be deconstructed), and the box will break long before it does. Damage never goes away either: colonists only repair buildings you own, and this one can't be claimed.

Workshop mods such as Advanced Life Support Unit and Minify Life Support Unit add a recipe, claiming or an uninstall option. They change the rules on this page, so read their requirements before you plan around them.

Can you take life support units home on a gravship?

Not in vanilla 1.6.4871. Three rules block it:

1. A unit travels with the wall it hangs on. When a gravship launches, wall fixtures come along only if their wall does, and the wall comes only if it stands on your gravship substructure.
2. Substructure can't go under walls or other structures you don't own. Try it and you get the message "Gravship substructure is blocked."
3. Fortified platform walls can't be claimed or deconstructed. They never become yours, so the substructure never fits under them.

Guides and videos from July 2025 show players carrying units off with their gravships. Those steps don't work on the current version. What you can do instead:

• Move in. Land your gravship at a cleared platform and build around the units. Seal the rooms, run conduits, and add hydroponics for food.
• Bring your own. For the ship itself, use oxygen pumps, heaters, batteries and chemfuel. The gravship guide covers the layout.

If a mod puts a unit on a planet, power and heat keep working. The oxygen part has nothing to do, because there is no vacuum to remove.

Life support vs. oxygen pump, heater and generators

Building	Power	Heat	Oxygen (per 100 tiles)	Can you build it?
Life support unit	+3,200 W	30/s, fixed 20°C	−5% / s	No. Orbital platforms only.
Oxygen pump	−150 W (15 W idle at 0% or when open to space)	None	−1% / s	Yes. Orbital tech, 100 steel + 2 components. Can be uninstalled.
Archean tree	None	None	−0.5% / s	Planted from rare seeds. Can't be replanted.
Heater	−175 W	21/s, adjustable (default 21°C)	None	Yes
Geothermal generator	+3,600 W	Bursts of heat while the geyser sprays	None	Yes, on a steam geyser
Chemfuel generator	+1,000 W	Some, from burning fuel	None	Yes, needs chemfuel

The oxygen pump is the only buildable source of air in vanilla, and it doesn't heat. Ships need pumps and heaters. Platforms with units only need the units, plus extra heat for big rooms.

Same name, different thing

A few other things share the name:

• Life Support (Workshop mod): a bed-linked machine that keeps a patient alive after losing vital organs. Not related to orbit.
• Save Our Ship 2: this ship mod has its own life support system and hypoxia rules. Its numbers don't apply to Odyssey.
• Advanced or Minify Life Support Unit: mods that let you build or move the Odyssey unit.

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