- That part of a boiler or warm-air heating plant in which combustion takes place.
- A complete heating unit that transfers heat from burning fuel to a heating system.
Origin & History of “furnace”
means roughly ‘warm place’. It comes via Old French fornais from
was a derivative of fornus
‘oven’, a word
related to formus
‘warm’, which goes back
to the same
-, as probably produced English warm