InstallationQuestion 24 of 110
When two combustion-air openings are used for an appliance in a confined space communicating with outdoors, they are generally located how?
a.Both near the floor
b.Both in the ceiling
c.One opening near the top and one near the bottom of the space
d.One in an interior wall only
Explanation
Two openings, one high and one low, allow both makeup combustion air and ventilation of heat. The high opening relieves warm air while the low opening supplies denser cooler air. The CMC sizes each opening based on appliance input and whether air comes from indoors or outdoors.
Law Reference: 2022 California Mechanical Code (CMC)Practice all 110 questions free — no signup required.
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