Category Iv Installations; Stainless Steel Venting; Cpvc Vent System Installation - Patterson-Kelley STORM ST-2500 Installation & Owner's Manual

Category IV Installations

If the vent installation is designed for Category IV conditions only (condensing – positive pressure) as it
is defined in ANSI Z21.13/CSA 4.9, latest edition. The installations shall be in accordance with NFPA
54/ANSI Z223.1, the National Fuel Gas Code, or CAN/CSA-B149.1, the Natural Gas and Propane
Installation Code, or applicable provisions of the local building codes.
pressure (Category IV). Harmful flue gases may leak into the room which can cause serious injury or
death.

Stainless Steel Venting

The following materials are used by venting manufacturers to produce listed venting systems.
•
AL29-4C Stainless Steel Vent Systems listed and labeled to UL1738 Venting Systems for Gas-
Burning Appliances, Categories II, III, and IV
•
316L Stainless Steel where certified and warranted by the vent manufacturer for venting of
Category II, III or IV appliances
These prefabricated venting systems must be installed according to the manufacturer's installation
instructions. Special care should be taken to ensure that any and all integral gasketing is properly
assembled and creates a gas and water tight seal. Systems that require silicone caulking for gasketing
should only be installed with silicone caulk that is recommended by the vent manufacturer, or if none is
recommended, only high temperature, waterproof, silicone caulk should be used. Support of venting
system must be according to the manufacturer's instructions. The boiler collar shall not be used to
support the weight of the vent.

CPVC Vent System Installation

Install CPVC vent systems in accordance with this manual and the SMACNA Thermoplastic Duct
Construction Manual. Install manufactured vent systems in accordance with the manufacturer's listing
and instructions. A customer supplied adapter is required to be installed between the boiler and the
CPVC venting.
Operating Parameters:
•
Maximum Water Temperature Set Point 180°F
•
Flue Gas Limit 194°F
Installation Parameters:
•
Cement and primer must conform to ASTM F493
•
Three feet of venting closest to the boiler must not be enclosed
•
The vent shall not be insulated
Revised: June 26, 2020
Released: June 26, 2020
Do not use a barometric damper if operating with a positive stack
CPVC Support Spacing (Feet)
Vent Size Sch. 40
4
6 4-1/2
8
10 5-1/2
12
© Patterson-Kelley 2020
All Rights Reserved.
P-K Storm
Technical Service 1.877.728.5351
Sch. 80
4 4-1/2
5
5 5-1/2
6
6 6-1/2
2691000273 P-K Storm ST2500-ST4000
Installation and Owners Manual Rev A.docx
TM
Gas Fired Boiler
Page 33