Chb - Wiring Diagrams - ECR International CHB Application Manual

CHB Boiler Wiring Diagrams
All field wiring shall conform to the authority having
jurisdiction or, in the absence of such requirements to:
USA: National Electrical Code, ANSI/NFPA 70,
Canada: Canadian Electrical Code, Part I, CSA
C22.1: Safety Standard for Electrical Installations.
A. CHB Single Zone Indirect Storage Tank is
NOT used:
• Terminals 7 and 8 (Key 155) on CHB terminal strip,
shall have two (2) factory supplied resistors wired in
parallel.
• Single room thermostat (Key 72) control internal pump
and boiler operation. Remove jumper when connecting
thermostat or zone equipment.
• See Wiring Figure 4.
B. When System Supply Pump is needed:
• External supply system pump connection terminals
(Key 307) are being added to the rear of the control
box and will be limited to an additional 1 Amp pump
operation. Internal control fusing will prevent higher
pump operation.
• If control IS NOT equipped with these terminals, or
larger pump capacity is required. Install an external
pump/relay controller circuit. See Instructions and
wiring diagram for adding external pump (615000137)
provided with this manual.
If control IS equipped with (Key 307) contacts and
•
larger than 1 Amp circulating pump is required, use an
isolation relay 120 VAC and separate 120 VAC power
supply. See wiring Figure 6. Manufacture recommends
use of isolation relay (240011284) or equivalent.

CHB - WIRING DIAGRAMS

C. Use of Indirect Storage Tank (DHW)/
Single Zone :
Terminals 7 and 8 (#155 in Key) resistors are removed.
Attach Indirect Tank Sensor element to terminals #7 and #8
(Key 155) on CHB terminal strip. See Figure 5.
Important:
• Before connecting the room thermostat,
remove jumper on terminal block. (Key 72)
• Before connecting optional Indirect Tank
Sensor, remove two (2) resistors. (Key 155)
• Before connecting Low Water Cutoff remove
jumper on terminal block. (Key 370)
8
NOTICE
Wiring Legend CHB/CCB
Pump - Zone
Thermostat
Indirect Tank (DHW Sensor)
S
Resistor
Valve - Zone
DHW Flow Switch (CCB only)
N.O.
PN 240011074 REV C, [11/01/2017]