A device built into an appliance which is designed to prevent a back draft from entering the appliance is a _______.

A device built into an appliance which is designed to prevent a back draft from entering the appliance is a _______.

• A. vent hood
• B. draft hood
• C. vent cap
• D. vent collar

Answer: (B)

Draft hood is a venting device built into an appliance to prevent backdraft from entering the appliance. It sits at the outlet of the appliance and provides a controlled opening that helps balance pressure in the vent system, allowing combustion gases to exit while preventing them from flowing back into the appliance when wind, cooler outdoor air, or other conditions push on the vent. This ensures safe and reliable venting for natural-draft appliances. Other options don’t serve this specific purpose: a vent cap mainly keeps rain and debris out of the vent, a vent collar is just a connector piece, and a vent hood (in other contexts) is typically the exterior cover or range hood—not the internal device designed to prevent backdraft into the appliance.

Draft hood is a venting device built into an appliance to prevent backdraft from entering the appliance. It sits at the outlet of the appliance and provides a controlled opening that helps balance pressure in the vent system, allowing combustion gases to exit while preventing them from flowing back into the appliance when wind, cooler outdoor air, or other conditions push on the vent. This ensures safe and reliable venting for natural-draft appliances.

Other options don’t serve this specific purpose: a vent cap mainly keeps rain and debris out of the vent, a vent collar is just a connector piece, and a vent hood (in other contexts) is typically the exterior cover or range hood—not the internal device designed to prevent backdraft into the appliance.