AERCO AM Series Boiler Cascade Sequencer Controller - Manual (Page 6)

AM Series Cascade Sequencer
INSTALLATION AND OPERATION MANUAL
1.2 Electrical Installation
The electrical installation must be done as shown in Figure 1-2.
Installer must install all wires represented by dashed lines. The “Cascade general sensor” is
present inside each heater’s accessory box. This sensor must be electrically wired to terminals
24 and 25 of the Managing heater # 1 and placed into the low loss header of the cascade (see
Figure 1-1).
The "daisy chain" wiring used to connect boilers should be shielded type and has a
maximum length of 300 ft. Unshielded wire is acceptable but not recommended, and the
maximum length is only 60 ft.
Depending on the control method of your system, additional wiring may be required. For
outdoor reset using the included outdoor temperature sensor, connect the outdoor
temperature sensor to terminals 14 & 15 of the managing boiler. For remote setpoint (0-10V)
control, connect the 0-10V signal wires to terminals 22 & 23 of the master boiler. For Modbus
control of the operating setpoint connect to terminals 18, 19, and 20. For further information
on Modbus, see GF-146-MB.
If there is a water heater tank present in the system, whether direct or indirect, the tank
sensor should be placed in the bottom 1/3 of the tank and wired into terminals 12 & 13 of
the managing heater. This sensor is included in the spare parts kit shipped with each unit,
and is the same probe as the cascade header temperature sensor.
For further information on all of these control modes, consult the AM Series Boiler and
Water Heater User Manual (GF-146).
Page 6 of 26 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0101_0A
PRI - 11/25/14 Ph.: 800-526-0288 GF-146-CS