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.

How to tell it is working

There is no separate "auto" mode and nothing to reset. The radiator's on/off switch is an AND gate:

• switch off → radiator is off, and stays off. The mod never turns it back on.
• switch on → the automation decides, moment to moment.

An auto-idled radiator shows the same "powered off" indicator icon as a manually switched-off one, and stops emitting its steam plume. That icon appearing on a radiator you did not switch off is the mod working.

Reading the diagnostic icons

The radiator reports its own internal state through indicator icons. An icon is drawn while its toggle is off, so:

Icon on a radiator	Meaning
🔧 wrench (MissingComponent)	Always expected. Its absence means the mod's components never merged onto the part, and nothing else in the mod is running.
thermal missile	No thermal-ammo signal is reaching this radiator — no launcher on its heat network is set to Thermal Canister Missiles.
resource	No hold signal is reaching this radiator — no thermal battery on its network is asking it to hold.
power-off	The radiator is idle: either you switched it off, or the automation idled it.

A correctly working setup, on a ship with a thermal launcher and a battery below the vent ceiling, shows the wrench alone.

These make the failure legible rather than guessable: wrench missing points at the patch mechanism, either other icon points at the specific signal that is dead.

Status

Validated against game data version 0.30.4c, and confirmed to load cleanly (Enabled mods: [User Folder] - ganter.auto_radiator).

v1.0.0 loaded without error and did nothing in game. It broadcast its signals with NetworkToggle / NetworkToggleReceiver. All three vanilla uses of those types set IncludeInPhysical = false — they are blueprint stat-display plumbing and carry no signal on a real ship, so every receiver read off, the vent gate was permanently open, and radiators behaved exactly as in vanilla.

v1.1.0 carried the signals as NetworkValue / NetworkValueReceiver instead, which is what vanilla's thermal amplification pump uses to drive actual physical behaviour. That was necessary but not sufficient: it also loaded cleanly and did nothing.

v1.2.0 added the diagnostic indicator icons, which is what finally located the fault. The wrench icon was present — so AddBase and the Overrides had been applying correctly the whole time — while both signal icons showed, meaning both NetworkValues read zero.

v1.3.0 fixes the actual cause. A network component is only attached to the network if a route reaches it: the part's NetworkPort anchors on one component, and a NetworkRouter bridges that anchor to every other network component on the part. That is how vanilla connects the radiator's own NetworkedThermalDissipationLoadValue, and how the amplification pump reaches the resonance beam turret. Unrouted components are not an error — they simply never connect and read as absent forever.

Routes were added from each part's anchor: NetworkedHeatBuffer on the radiator through its existing Router, plus a new NetworkRouter on the thermal battery, the missile launcher and base_part_overclock, none of which ships one.

Three separate mechanisms have now each produced a mod that loads without a single error and silently does nothing. The test suite has a mutation-verified guard for each: blueprint-only signal types, fields that do not exist in the real schema, and unrouted network components.

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.