P-K Storm
TM
Gas Fired Boiler
Technical Service 1.877.728.5351
Revised: June 26, 2020
Released: June 26, 2020
©
Patterson-Kelley 2020
All Rights Reserved.
2691000273 P-K Storm ST2500-ST4000
Installation and Owners Manual Rev A.docx
Page 40
Boiler Inlet and Outlet Connections
All water connections should be in compliance with national, state, and local code requirements. Adapters
from
Victaulic to NPT are available from Patterson-Kelley. The bottom rear connection to the boiler is the
INLET and must be used for the return from the system. The top rear connection to the boiler is the
OUTLET and must be connected as the supply to the system. All water piping must be installed such that
no stresses are transmitted to the boiler. The boiler
shall not
be used as a pipe anchor
.
Boiler Water Piping (for Installer)
Strainer
To avoid possible contamination of the boiler with dirt, rust, or sediment from the system, a strainer
near the boiler inlet is strongly recommended. Even new systems may contain sufficient foreign
material to eventually reduce the performance of the heat exchanger. Adequate circulation of good
clean water is essential for maximum efficiency and long life of the boiler. Refer to
Practices For New & Retrofit Systems
for more information on best piping practices.
Heat
Exchanger
Relief Valve Piping
Each boiler is supplied with a pressure-relief valve sized in accordance with ASME requirements. The
relief valve discharge must be piped to an acceptable drain at a safe point of discharge. Reducing
couplings or other restrictions are not permitted in the discharge line.
The PK Storm boilers require an ASME Section IV relief valve to be installed on the top of the OUTLET
(Supply) connection. The spindle of the relief valve must be vertical. The ASME Section IV relief valves are
available for purchase from Patterson-Kelley.
Low Water Cut-Off
The boiler is furnished with a probe-type low water cut-off; no field piping is required. If the water level in
the boiler drops below the probe, the boiler will shut down and LOCKOUT LOW WATER LEVEL will be
displayed on the control panel. The low water cutoff circuit will automatically reset
when the low water
condition clears; however, the boiler controls will retain the lockout condition until the reset button on the
display is depressed. Installation of external limit controls may be required by certain codes or in certain
installations. Review applicable local codes for details
.
Drain Valve and Piping
The P-K Storm
™
boilers feature a ¾” drain connection. Prior to draining the boiler, electrical power and
gas supply must be turned off to the boiler, and the boiler must be isolated from the system at the supply
and return connections
.
NOTICE!
Some local jurisdictions may require an auxiliary low water cut-off device installed in the
external piping. The auxiliary low water cutoff device only prevents operation when the water level
in the appliance is insufficient. It does not detect low water conditions in other parts of the system.
Installation of automatic air vents in the “high points” of the piping or additional low water safety
devices should be considered to protect the system.
NOTICE!
The 3/4” manual drain is for draining the water inside the heat exchanger only, not the
entire hydronic or domestic system. Draining the entire system through the boiler or water heater’s
drain valve will deposit sediment and debris from the system inside the heat exchanger. This will
result in poor heat transfer and premature failure. Refer to
for more information on best piping practices.
N
OTICE
!
The boilers require a minimum operating water pressure of 14.5 psi.
