Heat Management - display and controls
In the Secondary Screen, at the bottom left corner is the display and controls for heat management. In Advanced Missions (not to be confused with Advanced Pilot Mode) you will have to control and manage the heat created by your 'Mech.
To the left of the Auxiliary Screen display is the heat indicator, a bar graph representing the heat build up in your 'Mech. As the heat builds up through weapon fire or damage, the indicator will begin to rise, moving up from green to yellow to red, indicating the severity of the heat build up. Once the indicator gets into the red zone, it will begin affecting your HUD. Eventually your 'Mech will automatically shut down because it is overheated, leaving you vulnerable to attack. A numeric value in percentage is displayed above the heat indicator.
Your current speed will affect how fast your heat reduces. If you are at full throttle, heat from the engines will keep the heat level high. Terrain will also have an effect on your heat. Standing in water will reduce your heat faster.
Next to the heat indicator is the coolant level indicator. In mid and advanced pilot modes you can cool your 'Mech down by flushing coolant through its system. This bar indicates the amount of coolant available to your 'Mech for flushing. To flush a set amount of coolant through your 'Mech's systems, hit the flush button on the Secondary Screen. When in use, the bar will decrease indicating the loss of coolant. When the bar reaches the bottom, the flush function will automatically cut off, indicating no further coolant is available to flush. Different 'Mechs will have different amounts of coolant, and each 'Mech has a set number of flushes depending on how large the coolant tank is on that particular 'Mech. The coolant is not replenished once it is used up. Therefore, coolant conservation is important. The only ways to replenish your coolant is to use one of the repair bays (if available at that mission's location) or if your 'Mech is destroyed and you return to the mission in a fresh 'Mech.
Since there is a limited supply of coolant for each 'Mech, press and release the flush button, don't hold it. If you hold the button, you will flush your entire coolant reserve. If you are in a "hot" situation, the flush button will flash to indicate that it is available to quickly bring the heat back under control. If you have no coolant left, the collant level meter will show empty and the button will remain dim. Read about Heat Management Theories and Tips from the Veterans.