Firebox & Heating Oven
The firebox and the heating oven are machines capable of producing heat (TU) from furnace fuels for any machines that require heat to operate, such as the stirling engine. Only items are burnable in these; fluids can be burned in a fluid burner, and an electric heater can directly convert energy into heat.
Crafting
Both machines are crafted in an anvil. The firebox is crafted with the following materials:
The heating oven is crafted similarly:
Operation
Both machines are similar in operation. In order for them to transfer heat, another machine for receiving the heat must be placed on top, such that the copper heat plate on the receiving machine sits on top of the copper heat plate of the heat producing machine.
Once constructed, these machines can be filled with furnace fuel, which will burn until either the fuel runs out, or the heat buffer is filled. No fuel will be consumed if its buffer is full — as such, both machines are fairly efficient at conserving fuel.
The primary difference in these two machines lie in their speed: the firebox burns fuel much slower at full efficiency, whilst the heating oven produces 5x the heat, 8x faster. Despite its inefficiency, the heating oven is often preferred for its much higher heat outputs and heat capacity. However, it cannot be used for stirling appliances, as its direct base output (500 TU/t) will over-speed them; the heavy stirling engine does not have this issue.
Additionally, the heating oven can receive heat from other heat producing machines placed underneath it: multiple can be stacked for heat-hungry machines like the crucible. The heat received, however, is halved when transferring to the machine above. This can also be used to power stirling machines, as the standard heat intake limit is 300TU/t, and 250TU/t is just below.
Fuel Bonuses
Certain fuels confer bonuses to both burn time and heat produced, making them more valuable than others:
| Burnable Items | Burn Time | Burn Heat |
|---|---|---|
| Coal | +25% | +100% |
| Lignite | +25% | +100% |
| Coke | +25% | +100% |
| Solid Fuel | +50% | +200% |
| Rocket Fuel | +50% | +400% |
| Balefire | -50% | +1400% |