InstallationQuestion 23 of 110
What is the primary purpose of providing combustion air to a gas-fired furnace?
a.To cool the electronic controls
b.To supply oxygen for complete and safe fuel combustion
c.To increase supply air temperature
d.To reduce refrigerant pressure
Explanation
A gas furnace needs adequate combustion air so the burner receives enough oxygen for complete combustion. Insufficient air causes incomplete combustion, producing carbon monoxide and sooting. The CMC specifies required openings or ducts based on the appliance input and the confining space.
Law Reference: 2022 California Mechanical Code (CMC)Practice all 110 questions free — no signup required.
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