Piping; Gas Piping Overview; Natural Gas Piping - Patterson-Kelley STORM ST-2500 Installation & Owner's Manual

3.7 Piping

Gas Piping Overview

Before making the gas hook-up, make sure the boiler is being supplied with the type of fuel shown on
the boiler nameplate.
The boiler shall be installed such that the gas
ignition system components are protected from
water (dripping, spraying, rain, etc.) during
appliance operation and service (circulator
replacement, control adjustment, etc.).
The boiler is factory fire-tested and adjusted for proper
combustion. The gas train components are certified to
handle a maximum inlet pressure of 14" W.C. (1/2 psig).
Typical gas pressure supply for natural gas is 7" W.C. If
the available gas pressure exceeds 14" W.C., a suitable
additional intermediate gas pressure regulator of the
"lock up" type must be provided to reduce the pressure
to less than 14" W.C. Refer to the table below or the
appliance's label for the minimum inlet gas pressure.
Natural Gas
Note: When using a vented lock-up gas pressure regulator, the vent piping should be increased by
one pipe size for every 10 equivalent feet of length. Never connect vent piping that is smaller in size
than the gas regulator's vent port connection.
This unit comes with a sediment trap (drip leg) already installed. Patterson-Kelley recommends a union
connection ahead of the primary manual shutoff valve on the boiler. A gas piping schematic is shown
above. Gas piping should be installed in accordance with National Fuel Gas Code, ANSI Z223.1, latest
edition, and any other local codes which may apply; in Canada see CAN/CSA-B.149.1, latest edition.
In the Commonwealth of Massachusetts, the gas cock must be a "T-handle type."

Natural Gas Piping

The table below should be used to size the natural gas piping to the appliance. The approximate
energy content of natural gas is 1,000 BTU / cu. Ft:
Revised: June 26, 2020
Released: June 26, 2020
ST-2500
3.5" W.C 3.5" W.C.
Appliance Size (BTU/Hr)
2,500,000
3,000,000
3,500,000
4,000,000
© Patterson-Kelley 2020
All Rights Reserved.
Technical Service 1.877.728.5351
Simplified Gas Piping
ST-3000 ST-3500
3.5" W.C.
Natural Gas Requirement
(CFH)
2500
3000
3500
4000
Installation and Owners Manual Rev A.docx
TM
P-K Storm Gas Fired Boiler
ST-4000
3.5" W.C.
2691000273 P-K Storm ST2500-ST4000
Page 37