When sizing air supply openings using the total input of all appliances, which table applies?

When sizing air supply openings using the total input of all appliances, which table applies?

• A. 8.1
• B. 8.2
• C. 8.3
• D. 8.4

Answer: (B)

When determining air supply openings, you must ensure there’s enough combustion air for all devices that could be operating at once. That means adding up the input ratings of every appliance in the space and using the table that provides opening sizes based on that total input. This approach accounts for the collective demand rather than just one unit, ensuring openings are sized to supply sufficient air for all appliances simultaneously. Other tables correspond to different sizing methods (such as per-appliance sizing or other scenarios), but for total-input sizing, you use the table keyed to the sum of all appliance inputs.

When determining air supply openings, you must ensure there’s enough combustion air for all devices that could be operating at once. That means adding up the input ratings of every appliance in the space and using the table that provides opening sizes based on that total input. This approach accounts for the collective demand rather than just one unit, ensuring openings are sized to supply sufficient air for all appliances simultaneously. Other tables correspond to different sizing methods (such as per-appliance sizing or other scenarios), but for total-input sizing, you use the table keyed to the sum of all appliance inputs.