The minimum clearance from combustible material for a B vent connector serving a gas appliance with a draft hood is_______.

The minimum clearance from combustible material for a B vent connector serving a gas appliance with a draft hood is_______.

• A. 2 inches
• B. In accordance with the B vent listing
• C. Zero clearance
• D. 6 inches

Answer: (B)

The key idea is that vent clearances for a B-vent connector are determined by the vent system’s listing, not by a fixed number. B-vent components and draft hood connections are rated by their manufacturer, and the installation instructions spell out the exact minimum distance to combustibles for that specific product. Because different B-vent designs, insulation, and fittings have different heat characteristics, the safe clearance must come from the listing for that particular vent. That’s why the best answer is to follow the B-vent listing. It ensures you’re using the correct, code-compliant clearance for the exact vent system you’re installing. Fixed numbers like 2 inches or 6 inches aren’t universally correct because they don’t account for variations in the listed product. If a shield or additional protection is required, or if the listing specifies a different distance, you’d follow that.

The key idea is that vent clearances for a B-vent connector are determined by the vent system’s listing, not by a fixed number. B-vent components and draft hood connections are rated by their manufacturer, and the installation instructions spell out the exact minimum distance to combustibles for that specific product. Because different B-vent designs, insulation, and fittings have different heat characteristics, the safe clearance must come from the listing for that particular vent.

That’s why the best answer is to follow the B-vent listing. It ensures you’re using the correct, code-compliant clearance for the exact vent system you’re installing. Fixed numbers like 2 inches or 6 inches aren’t universally correct because they don’t account for variations in the listed product. If a shield or additional protection is required, or if the listing specifies a different distance, you’d follow that.