Auto Radiator

A Cosmoteer mod. Radiators stop dumping heat the ship still wants.

The problem

Thermal Canister Missiles are built from the ship's own heat. The game says so itself, in Data/strings/en.rules:

Manufactures guided Thermal Canister Missiles that take thermal energy from their own ship's heat pipe network and inflict it upon the target.

The launcher charges each missile from the heat network — HEAT_PER_MISSILE = 8500, two missiles buffered per launcher. A radiator pulls from that same network, through a component that is behaviourally identical to the launcher's:

	Radiator	Thermal launcher
Type	NetworkResourceOutput	NetworkResourceOutput
Mode	DistributeProportionallyByAvailable	DistributeProportionallyByAvailable
Categories	[ thermal_storage ]	[ thermal_storage ]

Data/ships/priorities.rules defines priorities for crew and supply only — nothing for heat. So the two compete flat, proportionally, and a radiator running constantly is spending your ammunition to make steam.

Why holding heat is safe

Heat storage being full does not hurt you. Damage comes only from overflow. Every overclocked part routes its heat through this (Data/ships/base_part_overclock.rules):

HeatDistributionStorage
{
	Type = MultiResourceStorage
	ResourceStorages = [NetworkHeatInput, OverflowHeatStorage]
	AddMode = InOrder
}

InOrder means the network is tried first, and OverflowHeatStorage only receives what the network refuses. Overflow then applies the cosmoteer.heat status to the producing part's own tiles.

From Data/statuses/heat/heat.rules, that status does nothing whatsoever below 350 per tile (RequireValueRangeForTick = [350, Infinity]). Fire chance ramps from 350 to 2500; thermal damage begins at 700.

An overclocked large reactor produces 2750 heat/sec over its 4×4 footprint — about 172 status/sec per tile while fully overflowing, so roughly 2 seconds of continuous, total overflow before fire risk even arms. Radiators react within 0.5 s (HeatDissipationConverter { Interval = 0.5 }).

At a 98% ceiling on a single 15000-capacity thermal battery, the overshoot during that reaction window is about 625 status heat spread over 16 tiles — roughly 39 per tile, against a threshold of 350. Holding the network near full is safe with a wide margin, and every percent of ceiling given up is ammunition thrown away for nothing.

The genuine constraint is not the threshold. It is total radiator throughput (1100/sec each) versus sustained generation. If you are short on radiators you overflow continuously and no threshold value saves you — which is what the safety net below is for.

What the mod does

Radiators vent when any of these is true:

1. The heat network is not asking them to hold — the thermal battery is at or above 98% full (dropping the hold again at 94%, a deadband so radiators do not chatter at the threshold).
2. No launcher on the network is set to Thermal Canister Missiles. If you are not spending heat as ammunition there is nothing to hoard, so radiators behave exactly as in vanilla.
3. Safety net: some part is actually overflowing heat right now. This reads the engine's own OverflowHeatStorage, so it fires the moment the network genuinely refuses heat — regardless of thresholds, pipe topology, or whether your radiator capacity was ever sufficient. Latched for 3 seconds so a stream of per-tick overflow events becomes one steady signal.

Your manual radiator on/off switch still overrides all of it. The automation can only idle a radiator you have left switched on.

Ships with no thermal battery have no broadcaster, so nothing changes for them. The signal polarity is deliberately "hold", not "vent", so that the absence of any part of this mod's machinery always falls back to vanilla behaviour.

No stat or number is changed. Only when radiators run.

Layout

mod.rules                                  manifest + patch actions
components/thermal_battery_vent.rules      decides when there is surplus
components/launcher_ammo_signal.rules      reports thermal ammo in use
components/overclock_overflow_signal.rules safety net, reports real overflow
components/radiator_auto.rules             combines the signals into one gate
tests/                                     offline validation suite
install.sh                                 validate + copy into the Mods folder

Install

./install.sh

Then enable Auto Radiator in the game's Mods menu. ./install.sh --uninstall removes it. If the script cannot find your Mods folder, set COSMOTEER_MODS_DIR.

Tests

python3 tests/test_mod.py

Cosmoteer applies mod actions to vanilla data at load time, and a path that does not resolve, a component reference pointing at nothing, or a misspelled component Type all fail identically: the game crashes on startup and leaves a log file. The suite parses the installed game's .rules tree and checks all three offline. It also self-checks the parser against known vanilla facts first, so a broken parser fails loudly instead of passing everything.

Set COSMOTEER_DATA to point at a different install.

Status

Validated against game data version 0.30.4c. The logic is verified statically — every patch target, component reference and component type is checked against the shipped .rules files — but it has not yet been run in-game. Worth watching on the first run: whether NetworkToggleReceiver with AllowUncategorized = false reads off on a ship with no broadcaster, which is the assumption the vanilla-fallback behaviour rests on.

Possible additions

• A per-radiator UI toggle for auto/manual, which needs a new ChoiceID wired into Data/gui/game/parts/part_toggles.rules.
• Making the 98% / 94% band configurable.