User:Uryence/newheat

This is a work-in-progress attempt to clean up and rationalise the Overheating page, retaining its useful information but giving players the key info they need initially and saving the math for later.

Overheating (or overloading) is an important ship combat mechanic in EVE Online. Any active module can be overheated, and overheating a module wrings better performance from it, at the cost of gradually-accumulating heat damage to the module.

Incautious overheating can burn a module out completely, making it useless until it is repaired. However, if used with care or in an emergency, the benefit gained from an overheated module could be the difference between losing your ship and killing your enemy. Good pilots know when the risk is worth the possible reward.

The timing of overheating and the management of the resulting heat damage are important parts of small-gang and solo PvP combat. Overheating remains useful in most larger PvP fleets. It has some niche uses in PvE combat.

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Provisional plan:

1. controls
2. uses of overheating
   1. (to include important highlights: boosting range on tackle modules, boosting DPS, boosting tanks (remember you can heat active hardeners too), boosting prop mod speed)
   2. table of bonus effects
3. heat and heat damage (key breakdown without math)
   1. explanation of heat and heat damage
   2. nanite repair paste
4. Overheating bonuses
   1. Relevant skills
   2. Ship bonuses (T3s)
   3. wormhole bonuses
5. the math

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Things to do:

1. new image of present-day interface
2. assess what is to be retained and what replaced
3. rewrite
4. one or more images of sensibly heatsinked fits: show how to separate out active modules and mitigate heat damage.
5. proofread
6. replace current page

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Controls

You can begin overheating a specific module by clicking the green light at the top of the module button. You can turn it off the same way -- note, though, that it won't turn on or off until the next cycle begins. Alternatively you can right click the module and choose to overheat it. You can also use a keyboard shortcut: by default you can overheat by holding down shift and pressing the key(s) required to activate a module normally. A module which has been set to overheat (or stop overheating) on its next cycle will have the green overheat light flash, until the new cycle begins and the overheat begins or ends. A module primed to overheat will stay primed after warping, but not after jumping or docking.

In some circumstances, you may need to overheat many modules as fast as possible. You can choose to overheat an entire rack (all the highslots, all the mid slots, or all the low slots) via the small buttons to the left of each rack.

The effects of overheating vary depending on the module. Most weapons will generate more damage (in the region of 15%). Tackling modules like webifiers get more range (about 20%). Propulsion devices like Afterburners boost your speed even more (roughly 50% more). With such benefits, it is easy to see that overheating is very powerful in the right circumstances.

There is also an option found by right-clicking the capacitor: "Lock Module Overheat State". When enabled, this blocks the ability to either overheat, or un-overheat (if they are already overheated), all modules. This can be used to prevent accidental overheating, however the inflexibility in it can just as easily cause other issues.

Not all modules can be overheated. For example, cloaking devices can't be overheated, and no passive modules can be overheated.

Heat Benefits

Any overheated module increases its performance in some way.

Key Benefits

A complete table of heat bonuses follows below, but some of the most important effects to know are:

• Heating a propulsion module provides an additional 50% speed bonus. Since speed and positioning are key to many kinds of PvP combat and to some kinds of PvE combat, this can prove crucial.
• Heating tackle modules boosts their range.
  • It is often worth pre-heating your point/scram/web when in warp towards an engagement, especially if you are likely to be the initial tackle, as greater tackling range at the beginning of a fight can make the difference between catching or losing a target.
  • Similarly, it is also often worth overheating tackle at the end of a fight, if your targets are trying to leave.
• Heating tank modules increases their effect.
  • This is simplest and most obvious for active tank modules: shield boosters and armour repairers both repair more per cycle and cycle faster when heated. Note that the faster cycle means a heaver capacitor burden.
  • Ancillary shield boosters and armour repairers should almost always be used overheated, since they already offer a short-term, "burst" tank.
  • Active resistance hardeners can also be overheated, however, and when heated they make your ship resist more damage. This means that overheating can also benefit some types of buffer tank and some types of passive shield tank.
• Heating all turrets and missile launchers increases their potential DPS, but not always in the same way.
  • Short-ranged turrets (pulse lasers, blasters, autocannon) get a bonus to their raw damage-per-shot.
  • Long-ranged turrets (beam lasers, railguns, artillery) get a bonus to their rate of fire. Note that an increased rate of fire also means an increased capacitor burden from beam lasers and railguns.
  • All kinds of missile launcher get a bonus to rate of fire.

At its simplest, overheating is a tool for high-stakes moments in combat, and a pilot in serious danger of losing their ship in either PvP or PvE is almost never wrong to overheat relevant modules. Some of the effects noted here, though, such as the tackle module range bonuses, are slightly subtler, and experienced pilots develop a sense of when to use them.

Table of All Heat Benefits

Sortable by Module Type, Overheat Effect, and Percent Bonus

Module Type	Overheat Effect	Percent Bonus
Afterburner Microwarpdrive	Speed Bonus	50%
Warp Disruptor Warp Scrambler	Range Bonus	20%
Stasis Webifier	Range Bonus	30%
Stasis Grappler	Optimal Range Bonus	300%
ECM Jammer Burst Jammer Tracking Distruptor Guidance Distruptor Remote Sensor Dampener Target Painter	Strength Bonus	20%
Energy Neutralizer Energy Nosferatu	Duration Bonus	-15%
Armor Hardener Shield Hardener	Strength Bonus	20%
Armor Repairer	Duration Bonus Strength Bonus	-15% 10%
Shield Booster	Duration Bonus Strength Bonus	-15% 10%
Hull Repairer	Duration Bonus	-15%
Remote Armor Repairer Remote Shield Booster Remote Cap Transmitter	Duration Bonus	-15%
Remote Sensor Booster Remote Tracking Computer	Strength Bonus	15%
Short Range Turrets	Damage Bonus	15%
Long Range Turrets	Duration Bonus	-15%
Missile Launchers	Duration Bonus	-15%
Tracking Computer Guidance Computer Omnidirectional Tracking Link Sensor Booster	Strength Bonus	15%
Cap Booster	Duration Bonus	-20%

Heat Damage

The downside of overheating is heat damage. Heat damage is not related to normal damage: overheating does not cause damage to your shield, armour, or hull hit points. Heat damage has no link to the Thermal damage type.

Rather, heat damage is dealt to the hitpoints of individual modules. If you "show info" on a module, and check its "Attributes" tab, you will see it has "Structure Hitpoints". Most modules have 40 hitpoints. TK find an image of this. Heat damage is dealt to these hitpoints.

The amount of heat damage on a module is visible as a red fringe that creeps around the circular module icon counterclockwise, from the 12 o'clock position. Having some heat damage does not affect modules' functions or power in any way. However, when a module has lost all of its hitpoints—when the red fringe has completely circled the module icon and reached 12 o'clock again—the module will stop working (or "burn out"). Note that if any single one of a grouped set of turrets or missile launchers burns completely out, the button for the whole group will become useless; it will be possible to continue using the other weapons, but only by ungrouping them (and if necessary regrouping them without including the burned-out module).

Damage Mechanics

The mathematics of heat damage is discussed in a later section for those interested. What all pilots should know about the mechanics heat damage is as follows.

Heat damage is not dealt reliably and automatically by every heated module cycle. Instead, it is dealt through a chance-based mechanic. Each heated cycle of any module always raises the heat level of the module's rack, by a reliably predictable amount: a heated cycle from a high slot module increases the high slot rack heat level, a heated cycle from a mid slot module heats up the mid slot rack, and so on. The following factors affect rack heat generation:

• Having more modules running overheated in the same rack generates more rack heat.
• Larger ships generate rack heat more slowly than smaller ships.
• Propulsion modules generate a lot of rack heat.
• Most T2 non-propulsion modules generate quite a lot of rack heat.
• All T1 non-propulsion modules and a few T2 modules generate a little heat.
• Faster-cycling modules tend to generate less heat per cycle.

Each heated cycle of any module has a chance to deal heat damage to the heated module, or to other modules in the rack. The chance of heat damage at the end of a cycle increases with the level of rack heat; how hot a high, medium, or low rack is affects how much of a chance of heat damage there is. The increase in the chance of heat damage caused by higher rack heat is not a steady, linear increase: high levels of rack heat generate a much higher chance of heat damage than low levels of rack heat. Rack heat is displayed in the three dials directly above the circle of the capacitor indicator. The leftmost dial displays low slot heat, the middle dial displays mid slot heat, and the rightmost dial displays high slot heat. TK add image of this.

Heat damage chances are also affected by proximity in the rack. A module is most likely to deal heat damage to itself; then to modules adjacent to it, then to other modules in the rack with the chance of heat damage decreasing with greater distance in the rack.

Preventing Heat Damage

In these low slots, the two active modules—armor repairer on the left, ancillary armor repairer on the right—have been put at opposite ends of the rack, to distance their heating effects from each other.

It is possible to overheat intelligently, in ways that limit the amount of heat damage caused.

In judging the risk of heat damage, rack heat is more important than the extent of damage already sustained, and the rack heat indicators can matter more than heat damage on a module button. If a rack is completely cool, it is usually safe to overheat for a cycle or two even with quite damaged modules: sometimes modules take no damage at all from a single cycle of heat when the rack starts out entirely cool. If, by contrast, a rack is very hot, it is quite risky to overheat even a module with little heat damage, as at high rack heat levels, damage will stack up very quickly.

The pilot of this Stabber has two small energy neuts fitted in the high slots, but as these are secondary tools and less likely to be heated than the guns, they are placed to space the guns out and absorb heat damage. In the mid slots, the shield extender—not an active module—is positioned to separate the often-overheated, strongly heat-generating MWD from the tackle modules.

Since the proximity of modules to each other affects their risk of heat damage, spreading out and separating active modules in a rack can mitigate heat damage. By placing the active modules in a rack as far away from each other as possible, the heat damage from each module can be spread out rather than concentrating on particular parts of the rack. Passive modules or less-important active modules can be placed in the slots between.

In the high slots of a combat ship, it is common to spread out the main weapon system modules as much as possible, putting secondary weapons, utility tools such as energy neutralizers, or command burst modules between the often-heated weapons. It is still possible to group the guns or launchers as normal. Pilots can move the module buttons around in space to keep them assigned to sensible keys in a logical arrangement, while retaining the "true" arrangement of modules in the fitting itself.

Players sometimes call this fitting practice "heatsinking", since the passive or less-commonly-used active modules placed between high-heat modules act as heat sinks. This idiom has no relation to the Heat Sink module, a low slot DPS-enhancing module for energy weapons; the Heat Sink module and its variations are no more effective as actual heat sinks than any other module.

Repairing Heat Damage

Heat damage sustained by modules can be repaired in three ways.

Nanite Repair Paste

An item called "Nanite Repair Paste" can be used to repair heat damage while in space. To do this, make sure you have some paste in your cargo hold, and then right-click on the damaged module button, and select "repair". Paste repairs take some time, enough time that they are generally applied between fights rather than during fights. Hovering over the repairing module's button will bring up a tooltip displaying the remaining repair time.

Repairs can be cancelled (right-click the module button and select the option to do this) and are cancelled automatically if your ship jumps through a gate, filaments, or travels via a jump to a cyno. The amount of repair carried out before cancellation will remain, and only the equivalent amount of paste will be used up.

Paste cannot be used to repair a module which is fully burned out.

Nanite Repair Paste is expensive enough that repairs in a station are always cheaper.

Tether

When tethered on a friendly Upwell structure, heat damage to a ship's modules is slowly repaired, for free. This does not repair full burned-out modules.

Docked Repairs

Heat damage can also be repaired, instantly, when docked up. In NPC stations this comes with a cost; in player-owned structures owned by friendly players and with appropriate settings, it can be done for free. Repairs while docked will repair fully burned-out modules too.

Overheating Bonuses

Several factors can enhance a pilot's ability to overheat.

Skills

The skill that lets pilots overheat is Thermodynamics (3x, 4.5M ISK). Thermodynamics reduces the heat damage caused by overheating by 5% per skill level, for a 25% reduction at level V. This is a starting skill for characters created between September 2015 and September 2019. Older and newer characters must train the requisites and this skill on their own.

There are also two skills which make paste repairs more efficient:

• Nanite Operation (2x, 1M ISK) - provides a 5% reduction in Nanite Repair Paste consumption per level.
• Nanite Interfacing (3x, 5M ISK) - provides a 20% increase in damaged module repair amount per second.

Bonused Ships

Tactical Destroyers and Strategic Cruisers have bonuses improving their ability to overheat. These bonuses are tied to the skills required to fly them:

• (Racial) Tactical Destroyer - Provides 5% reduction to heat damage from overheating per level.
• (Racial) Strategic Cruiser - Provides 5% reduction to heat damage from overheating, and 10% increase in damaged module repair amount per second, per level.
• (Racial) Core Systems - Provides 5% reduction to heat damage from overheating per level when the associated electronic warfare subsystem is fitted.

Both types of ship are able to overheat for longer. A Strategic Cruiser with an electronic warfare Core subsystem piloted by a pilot with all Strategic Cruiser skills trained to V will benefit from a 50% reduction in heat damage from overheating.

Red Giant Wormholes

Wormhole space systems with the Red Giant effect increase both the risk and the reward associated with overheating. Every Red Giant wormhole increases heat damage by a percentage, and increases the bonuses gained from overheating by twice that percentage.

	Effects	Class 1	Class 2	Class 3	Class 4	Class 5	Class 6
	Heat Damage	+15%	+22%	+29%	+36%	+43%	+50%
	Overheat Effect Bonus	+30%	+44%	+58%	+72%	+86%	+100%

Heat

Modules that are overheated generate heat. This heat builds up in the ship (separated by module racks), and causes damage other modules in the same rack. Heat damage is what limits the use of overheating and has to be balanced between the need for the extra boost, and the risk of losing the module.

Rack Heat

Module heat damage is handled on a rack-by-rack basis, with the High Power, Mid Power, and Low Power modules each being handled independent of each other. As overheated modules cycle, they build up heat within their racks. The three segmented bars in the center HUD, between the capacitor and hitpoint bars, are the heat indicators for the racks (in order left-to-right of low|mid|high). Rack heat generation occurs continuously while modules are overheating, at a rate based on the number of modules being overheated, the type of those modules, and the size of the ship overheating them. Larger ships generate rack heat more slowly than smaller ships.

Module Type	Rack Heat Generation/second
Afterburner, Microwarpdrive	4%
Most T2 modules	2%
All other non-T2 Modules	1%

Hull Size	Rack Heat Generation Rate
Frigate, Interdictor, Command Destroyer	100%
Destroyer, Tactical Destroyer	85%
Cruiser, Industrial, Mining Barge	75%
Battlecruiser	65%
Battleship	50%
Carrier, Force Auxiliary	40%
Dreadnought, Supercarrier, Orca, Rorqual	35%
Titan	25%

The values from these tables cannot be found in game. They must be found on outside sources. Module heat generation rates can be found on modules, under the attribute heatAbsorbtionRateModifier, and hull heat generation modifiers can be found on ship hulls, under the attribute heatGenerationModifier.

The time required for a rack to reach a certain heat level (starting from 0% rack heat) with a given set of overheated modules can be calculated with the following formula: H(t)=(heatCapacity/100)-e^(-t*heatGenerationMultiplier*sum(heatAbsorbtionRateModifier))

[math]\displaystyle \text{H(t)}= 1 - e ^ \left( \text{-t} \cdot \text{heatGenerationMultiplier} \cdot \text{sum} \left( \text{heatAbsorbtionRateModifier} \right) \right)[/math]

or, rearranged,

[math]\displaystyle \text{t} = \frac{-\ln{\left(1 - H(t) \right)}}{\text{heatGenerationMultiplier} \cdot \text{sum} \left( \text{heatAbsorbtionRateModifier} \right)} [/math]

where

• H(t) is the target heat level, as a decimal (for example, 90% = 0.9)
• t is the time in seconds
• heatGenerationMultiplier is the "Rack Heat Generation Rate" from the above table based on hull size
• sum(heatAbsorbtionRateModifier) is the sum of the "Rack Heat Generation/Second" (as a decimal) of all currently overheated modules in the rack

So for example, if a frigate overheating a Warp Scrambler I, it would take:

[math]\displaystyle \text{t} = \frac{-\ln{\left(1 - 0.5 \right)}}{1 \cdot \text{sum} \left( 0.01 \right)} = \frac{-\ln{0.5}}{0.01} = \frac{0.693}{0.01} = 69.3 [/math]

69.3 seconds to reach 50% rack heat, and

[math]\displaystyle \text{t} = \frac{-\ln{\left(1 - 0.9 \right)}}{1 \cdot \text{sum} \left( 0.01 \right)} = \frac{-\ln{0.1}}{0.01} = \frac{2.303}{0.01} = 230.3 [/math]

230.3 seconds to reach 90% rack heat

Meanwhile, if a Catalyst, with 8 Light Neutron Blaster II, were overheating its full gun rack, it would take:

[math]\displaystyle \text{t} = \frac{-\ln{\left(1 - 0.5 \right)}}{.85 \cdot \text{sum} \left( 0.02 \cdot 8 \right)} = \frac{-\ln{0.5}}{0.85 \cdot 0.16} = \frac{0.693}{0.136} = 5.1 [/math]

5.1 seconds to reach 50% rack heat, and

[math]\displaystyle \text{t} = \frac{-\ln{\left(1 - 0.9 \right)}}{.85 \cdot \text{sum} \left( 0.01 \cdot 8 \right)} = \frac{-\ln{0.1}}{0.85 \cdot 0.16} = \frac{2.303}{0.136} = 16.9 [/math]

16.9 seconds to reach 90% rack heat

This illustrates the speed at which large gun racks heat up and burn out, versus the much slower rate at which individual E-War or local repair modules will heat and burn.

The time required to increase rack heat from a given level to a target level is found by calculating the time required to reach the higher level, and subtracting the time required to reach the lower level. So, for that frigate to increase from 50% rack heat to 90% rack heat, it would take (230.3 - 69.3) = 161 seconds.

Rack Heat Dissipation

When no modules in a rack are being overheated, the rack will dissipate stored heat, at a rate proportional to how hot the rack is. The rate of dissipation is:

[math]\displaystyle \text{Heat Dissipation per second} = (\text{Current Rack Heat %}) \cdot 1\text{%}[/math]

For example, at 60% rack heat, the rack will lose heat at 0.6%/second.

Unlike with heat generation, heat dissipation is constant across all sizes of ships. However, Rack Heat is not immediately removed when a ship is docked or Repaired, it continues to dissipate at the normal rate; as a result, if a ship is docked to repair heat damage and immediately undocked, its racks may still have heat left in them even if its modules have been repaired.

The actual time required for a rack's heat to dissipate can be calculated using the following formula:

[math]\displaystyle \text{H(t)}= \text{H(0)} \cdot e ^ \left( \text{-t} \cdot \text{heatDissipationRate} \right)[/math]

or, rearranged,

[math]\displaystyle \text{t} = 100 \cdot \ln{\frac{\text{H(0)}}{\text{H(t)}}}[/math]

where

• t is time in seconds
• H(t) is the target heat level, as a decimal (for example, 90% = 0.9)
• H(0) is the initial heat level
• heatDissipationRate is 0.01 (on all ships)

So, for example, the time required for a ship to drop from 90% rack heat to 50% rack heat is equal to

[math]\displaystyle \text{t} = 100 \cdot \ln{\frac{0.9}{0.5}} = 100 \cdot 0.58778 = \text{58.8 seconds}[/math]

and the time required to drop from 50% rack heat to 20% rack heat is equal to

[math]\displaystyle \text{t} = 100 \cdot \ln{\frac{0.5}{0.2}} = 100 \cdot 0.91629 = \text{91.6 seconds}[/math]

The logarithmic nature of this formula implies that actually reaching 0% rack heat is impossible, so at some low value (unknown but below 1%) the server simply rounds down to 0%. If we assume that low value is 0.5%, then the maximum possible heat dissipation time is

[math]\displaystyle \text{t} = 100 \cdot \ln{\frac{1.0}{0.005}} = 100 \cdot 5.2983 = \text{529.8 seconds}[/math]

-Which is just less than 9 minutes.

The following is a quick-reference table of heat dissipation times

Heat Level	100%	90%	80%	70%	60%	50%	40%	30%	20%	10%	1%
Time to lose next 10%	10.5s	11.8s	13.4s	15.4s	18.2s	22.3s	28.8s	40.5s	69.3s	230s	-
Cumulative loss time from 90%	-	-	11.8s	25.2s	40.6s	58.8s	81.1s	109.9s	150.4s	219.7s	449.7s

Module Heat Damage

Every time an overheated module's cycle ends, that module has a chance to deal Heat Damage (not to be confused with the Thermal Damage dealt by ship weapons) to itself and other modules on the same rack. The amount of damage a module will deal to other modules on an overheat cycle is visible in game in a module's Show Info window, under the name Heat damage. These values are generally higher for smaller-ship modules, lower for larger-ship modules, and somewhat proportionate to the modules' cycle times. (Faster-cycling modules generally have lower heat damage.) This Heat Damage value is the value which can be reduced by the skills listed at the top of this page. This is also the value which is increased by the negative system effect of Red Giant Wormhole systems. Modules will not always deal heat damage to themselves or others on every cycle ending, but when they do deal heat damage they will always deal exactly their listed amount of damage. Modules which have sustained heat damage will start to show red outlines around their icons in the hotbar (more red indicating more heat damage). The red outline will flash when a module sustains further heat damage from additional overheat cycles.

Module heat damage can be repaired in three ways:

• Docking in a Starbase with a Repair Shop, or an Upwell Structure, and either bringing up the Repair Shop window from the starbase menu, or right-clicking on the damaged ship (or modules if they are unfitted) and selecting Get Repair Quote. Repairs in an NPC-owned station cost ISK.
• Tethering to an Upwell Structure. While Tethered to an Upwell Structure, the Tether effect will repair module heat damage as well as the more visible shield/armor/hull/capacitor repairs it grants. However, this repair can be inconsistent at times, and either may not repair all damaged modules or may not repair them fully.
• Consuming Nanite Repair Paste. Right-clicking the icon for a damaged, not-actively-cycling module in the hotbar will bring up a menu, containing the option Repair and a number in parentheses. That number is the amount of Nanite Repair Paste that will be consumed to perform the repairs. Selecting this option will begin to slowly repair the module (but will not immediately remove the Paste from cargohold) .
  • Paste used in repairs is removed from cargo when the repair completes. While a module is being repaired, the module cannot be activated, and no other modules on the ship can be overheated.
  • Repairs can be cancelled from the same right-click menu. Cancelling a repair before it is complete (including jumping a gate) will stop the repair at its current point, and remove repair paste from cargo based on how far the repair got. Jumping through a stargate will automatically cancel any repairs.
  • It is not possible to begin repairing a module if there is not enough paste in cargo to fully finish repairing it.
  • It is possible to repair a module while it is being Reloaded. This is a commonly recommended tactic for use on Ancillary repair modules and Rapid missile launchers: Overheat the modules while they are in use for their limited cycles, and then Repair the heat damage sustained during their long reload cycles.

Module Burnout

Every module has a certain amount of hitpoints (visible in its Show Info panel as Structure Hitpoints). In almost all cases, this value is 40HP, however for certain capital ship modules like Doomsday Weapons the value is in stead 99999HP or 999999HP (indicating that these modules effectively cannot be burned out by other modules' heat damage). If a module sustains heat damage exceeding its structure hitpoints, the module will 'burn out', and be forcibly set offline. A burned out module cannot be repaired with Nanite Repair Paste, and cannot be set online again or activated until it has been repaired. However, burned out modules are not destroyed or otherwise lost. Ideally, burned out modules should be repaired via a starbase or structure repair shop, however if a burned out module is partially repaired by being Tethered to an Upwell Structure, it can be brought online again while still in space. Burned out modules do not automatically re-online after being repaired; they must be manually reactivated.

Module Heat Damage Odds

As was mentioned, modules being overheated can, but may not always, deal heat damage to themselves and other modules. The odds of this happening is based on several factors:

• The Rack Heat of the rack being overheated. As Rack Heat rises, the odds of heat damage instances occurring increases, and the odds of larger numbers of modules being damaged by one proc increases. In the past, this was erroneously believed to be a simple 1-4 multiplier on the number of modules that could be damaged at once, but in reality it acts as a percentage chance for a given module to receive heat damage, after the results of the other factors. (It is theoretically possible for every single module in a rack to be damaged by a single overheat cycle, however in practice this is highly unlikely.)
• The placement of modules in the rack. Modules that are being overheated have the highest chance to deal heat damage instances to themselves and to immediately adjacent modules. Every additional module slot of distance away from an overheating module reduces the chances of that other module being damaged, to the point that modules on opposite ends of a rack have the lowest chances to damage each other. If a module is on the far end of a rack, or has only empty slots to one side of it, it may attempt to deal heat damage to the nonexistant modules off the end of the rack, which will result in the module itself erroneously flashing to indicate heat damage being dealt, and no heat damage actually being dealt in that direction. The result of this is that in a rack where only a small number of modules will be overheated, the best slots to place those modules is either on one far end (for one overheating module), opposite far ends (for two), or as evenly spaced across the rack as possible (for more); and the worst slots to place overheating modules in is either the center of the rack (causing it to damage all other modules in the rack) or adjacent to another to-be-overheated module (as they will damage and burn each other out). Note that these module placements apply to the fitting screen, not the hotbar; the placement of module buttons on the hotbar does not matter.
• The number of Online, versus Offline or Empty, slots in the ship. The odds for any module to sustain overheat damage is based on the total number of Online modules on the ship, divided by the total number of high, mid, low, and rig slots on the ship. (Rigs do not count as online modules for this calculation.) This means that having one or more module slots on a ship empty, or one or more modules Offline, will reduce the chances of all modules on the ship sustaining heat damage. It also means that there is always a chance for an overheated module to not take damage on every heat cycle.
• The ship, and the hidden heatAttenuation value for the rack. Every ship hull has three hidden attributes (named heatAttenuationHi, heatAttenuationLow, and heatAttenuationMid). In general, the values of these attributes correspond to the number of slots in the rack, with the numbers being higher for racks with more slots; however there are a small number of ships which have received balance changes to their slot counts but not had their attenuation values changed. Higher values of these attributes represent greater chances for heat damage to spread across adjacent modules down the rack. The value of the attribute is a decimal chance for the heat to spread to each further module, meaning that the chance for a given module to receive heat damage is equal to the heatAttenuation factor, raised to the power of the distance (in slots) between the overheated module and the module being damaged.

Heat Attenuation Values

In most cases, the number of slots in a rack directly corresponds to that rack's heatAttenuation attribute

Slot count	heatAttenuation
1	0
2	0.25
3	0.5
4	0.63
5	0.707
6	0.758
7	0.794
8	0.82

The Master Overheat Damage Formula

The odds for a given module to sustain overheat damage on a single cycle can be condensed into one formula:

[math]\displaystyle \text{Damage Chance}= \text{Rack Heat} \cdot \left( \frac{\text{Online Hi+Mid+Low Modules}}{\text{Total High+Mid+Low+Rig Slots}} \right) \cdot \text{heatAttenuation}^\mathrm{Distance}[/math]

For example:

• An Enyo (slots 5/3/4, 2 rigs), with 1 empty High slot, at 60% Rack Heat, overheating a Warp Scrambler in mid rack slot 1.

Odds of damaging the Warp Scrambler itself:

• Damage Chance = 0.6 * [4+3+4 / 5+3+4+2] * [0.5 ^ 0]
• Damage Chance = 0.6 * [11 / 14] * 1
• Damage Chance = 0.6 * 0.786 * 1
• Damage Chance = 0.471 = 47.1%

Odds of damaging the modules in slots 2 and 3:

• Slot 2 = 0.6 * [4+3+4 / 5+3+4+2] * [0.5 ^ 1]
• Slot 2 = 0.471 * 0.5
• Slot 2 = 0.236 = 23.6%

• Slot 3 = 0.6 * [4+3+4 / 5+3+4+2] * [0.5 ^ 2]
• Slot 3 = 0.471 * 0.25
• Slot 3 = 0.118 = 11.8%

Heat Sinking

Not to be confused with the module which increases Energy Turret damage, Heat Sinking is the commonly discussed practice of including either empty slots or unused modules to absorb heat damage in a rack and increase the lifespan of other modules in the rack. As has been demonstrated by the above section, this can be an effective and valuable strategy, including one or more empty slots or offline modules in a rack of otherwise hot modules. This is most commonly done in a ship's high slots, as mid and low slots are generally seen as far too valuable to sacrifice, but as has also been demonstrated, there are both correct and incorrect ways to heat sink a rack. The correct way to heat sink a rack of modules (usually weapons) is to spread the weapons as far apart and as evenly as possible, and then evenly intersperse a set of either Offline modules or Empty slots in between the guns. (Don't give up a Turret or Launcher Hardpoint just to get a better heat sink though. You still want to have the full set.) The incorrect way to heat sink a rack is either to leave all of the modules lined up next to each other (as the fitting system will usually do by default), or to evenly intersperse additional Online modules across the rack.

It is also possible in emergency combat situations to Offline non-essential modules in the heat of battle, to buy critical modules a little more overheat time. This is most commonly done with Microwarpdrives in fights with no way to escape a scram (however this is often more to remove the MWD's capacitor penalty than to use its slot for heating).

External links

• Jester's Trek: Guide to Overheating (2011), and old page on general overheat mechanics
• How does module spacing affect heat damage?, a guide video on module spacing in slots
• Turning down the heat (Overheating part 2), a follow-up to the above video (also linked in the above text), on the effects of empty slots versus unused modules
• The original EVE Forum thread by Kadesh Priestess (2011), containing his research on overheat math
• Everything you need to know about heat (2019), a complete guide video by Suitonia (which references both this article and Kadesh's thread, and can be viewed as 'this article, but in video form')