ECR International CHB Application Manual page 9

FIGURE 4 - CHB Boiler with Optional Supply System Pump Single Zone - No Indirect Tank (DHW)
KEY 72
T T
T
Low Voltage
Room Thermostat
FIGURE 5 - CHB Boiler Single Zone with DHW Indirect Tank and Sensor
KEY 72
T T
T
Low Voltage
Room Thermostat
CHB - WIRING DIAGRAMS
CHB BOILER
KEY 370
3 4
1 2 5 6
Remove
Jumper
10K
if used
1.8K
CHB BOILER
KEY 370 Key 155
1 2 3 4 5 6
Remove
Jumper
if used
DHW Sensor
Remove two (2) factory installed
Resistors when using Indirect
Tank Sensor on Key 155.
[Use kit 550002958]
Key 155
7 8
Resistors (Factory wired)
7 8
Indirect Tank
S
9
System Supply
Pump Connection
L1 (Hot)
Key 307
GND
NEU
120 VAC
POWER SUPPLY Cord
120V/60HZ
System Supply
Pump Connection
L1 (Hot)
GND
Key 307
NEU
120 VAC
POWER SUPPLY Cord
120V/60HZ
PN 240011074 REV C, [11/01/2017]
CH System
Pump
(If Used)
CH System
Pump
(If used)