Gas PipingQuestion 253 of 360
Why must clearances to combustibles for a single-wall metal vent connector and for Type B vent be respected during installation?
a.Only to make the job look neat
b.Clearances apply only to gas piping, not vents
c.Because vents never get hot
d.Because vent surfaces can reach temperatures that ignite nearby wood or paper if the listed clearance is not maintained
Explanation
A vent connector carries hot combustion products, and its surface can reach temperatures that ignite adjacent combustibles if the listed clearance is not kept. Single-wall connectors require larger clearances than double-wall Type B vent because they radiate more heat. Always follow the clearance-to-combustibles values on the vent listing and appliance instructions.
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