Patterson-Kelley P-K STORM ST-8000 Installation And Owner's Manual page 21

Vent Sizing for Category II / IV Operation
The vent must be sized in accordance with the
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.
The combustion air flow rate requirements per boiler model are summarized in 3.4.3. When sizing the
combustion air intake ductwork, the pressure drop through this ductwork MUST NOT exceed 0.22"
W.C. for the 2500-4000 and MUST NOT exceed 0.5" W.C. for the 5000-8000 as described in the table
below:
®
P-K STORM Boiler Model
ST-2500, ST-3000,
ST-3500, ST-4000
ST-2500, ST-3000,
ST-3500, ST-4000
ST-5000, ST-6000
ST-8000
NOTE: ST-2500-ST-4000: Total combined vent pressure not to exceed 0.44" W.C.
ST-5000-ST-8000: Total combined vent pressure not to exceed 1.0" W.C.
Revised: February 2, 2024
Released: February 2, 2024
ASHRAE
Draft Stack Temperature
Category II
-0.01" to -0.05" W.C.
Category IV
+0.01" to +0.44" W.C.
Category IV
+0.01" to +1.0" W.C.
 Patterson-Kelley 2024
All Rights Reserved.
P-K Storm
Technical Service 1.877.728.5351
Systems and Equipment handbook (Chapter
220 °F (gross)
220 °F (gross)
220 °F (gross)
2691000403 P-K Storm ST2500-ST8000
Installation and Owners Manual Rev G.docx
®
Gas Fired Boiler
CO
2
Natural Gas
8.75%
8.75%
8.75%
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