Patterson-Kelley P-K STORM ST-1250 Installation & Owner's Manual page 65

Drain and flush the water side of the heat exchanger as required (separate from system flush)
using clean water only. This heat exchanger comes with a drain valve; it is located on the back
of the heat exchanger above the exhaust vent. To flush water side of heat exchanger, it is
recommended to first isolate the boiler from the system. Remove pressure from the boiler
piping. It is then recommended to attach a hose or piping to the drain valve on the heat
exchanger. That hose (or piping) should be run to a floor drain. Open the drain valve to drain
water from the boiler piping. It is then recommended to remove the flow switch from the outlet
piping. Once the flow switch is removed, utilize the 1" NPT opening to attach a hose. The hose
should then be pressurized with clean water, with the drain valve to the boiler open and piped to
a floor drain. Flush the heat exchanger for several minutes. When complete, remove any hoses
or piping, and reinstall components to their operating positions.
DO NOT ALLOW THE DRAIN VALVE TO BE OPEN INSIDE THE CABINET WITHOUT
***Do this flush at low pressures— just enough pressure to push water through the
OUTLET
INLET
DRAIN
VALVE
Revised: October 2, 2019
Released: October 2, 2019
RUNNING PIPE OR HOSE TO A DRAIN.
exchanger and out of the drain valve***.
Note: Shown from Left Side with Side Panels Removed for Clarity
 Patterson-Kelley 2019
All Rights Reserved.
P-K Storm TM Gas Fired Boiler
Technical Service 1.877.728.5351
2691000099 P-K Storm Installation and Owners
Manual.docx
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