A furnace is used to heat ___
A)water
B)air
C)a refrigerant
D)radiant coils
Air
To determine the answer to this question, we can think about how a furnace works and the typical uses for a furnace.
A furnace is a heating device that generates heat by burning fuel or using electricity. The heat is then transferred to a medium, which is typically air, water, or another substance. The heated medium is then used to provide warmth or perform a specific function.
Now, let's consider the options:
A) Water: A furnace can be used to heat water. This is commonly done in a central heating system, where a furnace heats water that circulates through radiators or underfloor pipes to provide warmth in a building.
B) Air: A furnace is commonly used to heat air. In forced-air heating systems, a furnace heats the air, which is then distributed throughout a building using ductwork and vents.
C) A refrigerant: A furnace is not used to directly heat a refrigerant. Refrigerants are typically used in cooling systems, such as air conditioners or refrigerators, in which heat is extracted from a space rather than being added to it.
D) Radiant coils: A furnace can heat radiant coils. Radiant heating systems use electric coils or hot water pipes to generate heat, and a furnace can supply the heat source for these coils.
Based on this analysis, the answer is either A) water or B) air, depending on the intended use of the furnace.