P-K Storm
TM
Gas Fired Boiler
Technical Service 1.877.728.5351
Revised: October 2, 2019
Released: October 2, 2019
Patterson-Kelley 2019
All Rights Reserved.
2691000099 P-K Storm Installation and Owners
Manual.docx
Page 25
Vent Sizing
The vent must be sized in accordance with the ASHRAE Systems and Equipment handbook, Chapter
30 or according to the vent manufacturer
’s recommendations. When using manufactured venting
systems, consult your vent supplier for correct sizing and structural support requirements. See the
table below table for vent design parameters.
P-K STORM
™
Boiler Model
Draft
Stack Temperature
CO
2
Natural Gas
ST-1250, ST-1500,
ST-1750, ST-2000
Category II
-
0.01” to -0.05” W.C.
220 °F (gross)
8.5%
ST-1250, ST-1500,
ST-1750, ST-2000
Category IV
(Sealed Combustion)
+0.01” to +0.22” W.C.
220 °F (gross)
8.5%
ST-1250, ST-1500,
ST-1750, ST-2000
Category IV
(Exhaust Only)
+0.01” to +0.4” W.C.
220 °F (gross)
8.5%
Vent Termination
For interior clearance requirements, refer to
The vent shall extend at least three (3) feet
above the roof, or at least two (2) feet above the highest part of any structure within ten (10) feet
of the vent. This is illustrated in the following diagram.
Additionally, the boiler vent shall terminate at least 3 ft. above a forced air inlet located within 10 ft.
