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 18
Low Voltage (TB1) Terminal Block
Enable/Disable
–TB1-1 and TB1-2 can be used to remotely enable or disable the boiler. The
functionality of these terminals is user-configurable through the NURO
®
controls, but generally closure
of the Enable/Disable circuit provides a call for heat to the boiler. Opening this circuit prevents the
boiler from running.
4-20mA Analog Input
– TB1-3 and TB1-4 can be used to provide a remote analog 4-20mA control
signal to the boiler.
This analog signal can be used to change the boiler’s operating setpoint/firing rate.
Spare Analog Input
– TB1-5 and TB1-6 are reserved for future use.
NOTE:
The boiler ships with a factory-installed jumper across the Enable/Disable terminals. This
circuit is energized with a 24VAC potential, so the contacts on any remote enable devices must be
rated for minimum 24VAC.