Electric Resistance Heaters
Kapton Film and Cartridge Heater Elements
Electric resistance heaters, comprising flexible Kapton polyimide film elements and high-watt-density cartridge heaters, maintain equipment above minimum survival temperatures within the active thermal control system. Flexible film elements conform to curved surfaces, while cartridge units heat fluid lines and valves using nichrome resistance wire and aluminum heat spreaders. Operation is critical during the 336-hour lunar night, when the loss of solar power makes heating the primary electrical load on nuclear or radioisotope power sources. Thermostat-controlled cycling and redundant circuits prevent single-point freezing failures across protected zones while minimizing power draw.
Electrical resistance heaters maintaining minimum temperatures during lunar night
Purpose
Prevent equipment from cooling below survival limits during 336-hour lunar night
Context
Child of L2-TCS-HTR in the Active Thermal Control System
Principles
- ▸Kapton flexible heaters conform to curved surfaces for efficient thermal coupling
- ▸Cartridge heaters provide high watt-density heating for fluid lines and valves
- ▸Thermostat-controlled cycling maintains temperature within deadband
- ▸Power consumption is primary energy demand during lunar night operations
Typical implementations
- ▸Minco Kapton polyimide film heaters (space heritage)
- ▸Watlow cartridge heaters for fluid lines
- ▸ISS heater system design heritage
Lunar considerations
- ▸336-hour lunar night creates massive heating power demand
- ▸Heater power must come from nuclear/RTG during night (solar unavailable)
- ▸Redundant heater circuits prevent single-point freezing failures
- ▸Heater placement optimized to minimize total power while protecting all critical zones
Specifications
Functional
| primary function | Electrical resistance heaters maintaining minimum temperatures during lunar night |
Physical
| materials | Kapton polyimide film, Nichrome resistance wire, Aluminum heat spreaders |
Interfaces
Provides
- Minimum temperature maintenance for all equipment zones
Requires
- Electrical power for heater elements (1-5kW during night)
Cite this entry
Lunar Ark Codex. "Electric Resistance Heaters" (L3-TCS-HTR-ELEC). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-TCS-HTR-ELEC
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.