It is one of the several scrap items that can be used in the construction of weapons and ammunition using schematics. In Fallout 3, one is needed in the creation of a Shishkebab. In Fallout: New Vegas with the Dead Money add-on installed, one is required to craft a gas bomb and the Cosmic knife super-heated.
You can easily find these by searching ovens (found in many abandoned houses, for instance in Minefield), or they may also be found in some workshops. A pilot light can be obtained early in the game by searching through Silver's stove inside her house in Springvale or in the RobCo Facility.
Fallout: New Vegas
Similar to Fallout 3, pilot lights in Fallout: New Vegas can be found in ovens. You can find many more in the basement of the REPCONN Test Site, especially in the storage room in the south-west. There are also several of them lying on the floor across the whole basement.
- One can be found in Nelson house
- Novac, in Jeannie May Crawford's house, in the oven.
- One can be found in oven at Fields' Shack.
- In an oven inside a house in Goodsprings.
- Some can be found in Novac near the gas station, on top of the shelves
- A pilot light, as its name suggests, uses a small gas flame to ignite a larger source of heat, such as in a gas oven. In our world an electrical spark has become a more common method of gas oven ignition, another thing that diverged between the Fallout universe and our own.
- In the Tranquility Lane simulation, loosening the pilot light in Martha Simpson's oven and asking her to start it will result in a gas explosion, killing her.
- The Fallout: New Vegas unmarked quest Not Worth a Hill of Corn and Beans requires 2 pilot lights.