Code C.2.16 Amendment

[hvacstudent]

C.2.17
For Single Appliance Venting Applications:
Where the vertical vent has a larger diameter than the vent connector, the vertical vent diameter shall be used to determine the minimum vent capacity and the vent connector diameter shall be used to determine the maximum vent capacity. The flow area of the vertical vent shall not exceed 7 times the flow area of the listed appliance categorized vent area, flue collar area, or draft hood outlet area unless designed with approved engineering methods.

I am a bit confused about this amendment. If the vent connector is 3" and the B vent chimney size is 6", can my vent connector be 6"? because how can you use the smaller vent to determine the maximum vent capacity and use the larger vent to determine the minimum vent capacity?

[Admin]

I don't have a C.2.17.

Do you mean C.2.16?

C.2.16
For Single Appliance Venting Applications:
Where the vertical vent has a larger diameter than the vent connector, the vertical vent diameter shall be used to determine the minimum vent capacity and the vent connector diameter shall be used to determine the maximum vent capacity. The flow area of the vertical vent shall not exceed 7 times the flow area of the listed appliance categorized vent area, flue collar area, or draft hood outlet area unless designed with approved engineering methods.

For Multiple Appliances Venting Applications:
Where 2 or more appliances are connected to a vertical vent or chimney the flow area of the largest section of vertical vent or chimney shall not exceed 7 times the flow area of smallest listed appliance categorized vent area, flue collar area, or draft hood outlet area unless designed with approved engineering methods.

If you're in Ontario follow Director's Advisory FS-065-05,

https://www.hvactechgroup.com/article.php/20070429181100239

[hvacstudent]

Thank you Admin for the info. The 7 times part is a bit confusing to me. Well, the whole C.2.17 is confusing to be honest. Thank you for the assistance.