STEP 5: CORRECT EQUIVALENT INPUT FOR
SYSTEM K-FACTOR
The capacities listed in Table 1.8.15C are based
on a system k-factor equal to 7.5. For any other
k-factor, the vent capacity must be adjusted. This
is accomplished by adjusting the equivalent input
for the system using a k-factor correction factor,
designated F3.
Refer to Table 1.8.15E for the equivalent input
correction factor which applies to the k-factor
calculated in Step 4. This factor is designated as
F3.
Multiply the equivalent input calculated in Step 2
times factor F3 from Table 1.8.15E. This step will
yield a new equivalent input, I:
I = MBH x F1 x F2 x F3 eq. 15E
Using this adjusted equivalent input, check the
stack diameter by following Steps 2 thru 3 again.
If the stack diameter remains the same, the sizing
is complete. If not, redo Steps 4 thru 5 etc. until
an acceptable result is achieved.
Table 1.8.15E: K-Factor Equivalent Input Correction Factor F3
K- Factor F3 K- Factor F3 K- Factor F3 K- Factor F3 K- Factor F3
1.00 0.37
1.50 0.45
2.00 0.52
2.50 0.58
3.00 0.63
3.50 0.68
4.00 0.73
4.50 0.77
5.00 0.82
5.50 0.86
6.00 0.89
6.50 0.93
7.00 0.97
7.50 1.00
8.00 1.03
8.50 1.06
9.00 1.10
9.50 1.13
10.00 1.15
10.50 1.18
11.00 1.21
11.50 1.24
12.00 1.26
12.50 1.29
13.00 1.32
13.50 1.34
14.00 1.37
14.50 1.39
15.00 1.41
15.50 1.44
16.00 1.46
16.50 1.48
17.0 1.51
17.50 1.53
18.00 1.55
18.50 1.57
19.00 1.59
19.50 1.61
20.00 1.63
20.50 1.65
21.00 1.67
21.50 1.69
22.00 1.71
22.50 1.73
23.00 1.75