AERCO BMK 2000DF - Manual (Page 75)

Benchmark 1500DF - 2000DF Boilers
CHAPTER 5 – MODE OF OPERATION
OMM-0098_0A AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 Page 75 of 196
GF-144 Ph.: 800-526-0288 04/01/2014
will ask the BLDG PRIORITY boilers to help with domestic hot water heating if the DHW
PRIORITY boilers are not able to satisfy the domestic hot water demand.
When the combo units are satisfying the domestic load, they are in the constant setpoint mode
of operation. When the combo units switch over to space heating, their mode of operation
changes to follow the ACS command. For more information concerning the operation of the
ACS, consult the ACS Operations Guide, GF-131. For more information on the ACS Relay Box,
see section 2.14 in the same manual.
5.7.1 Combination Control System Field Wiring
Wiring for this system is between the ACS, the ACS Relay Box, and the terminals in the I/O
Box. Wire the units using a shielded twisted pair of 18 to 22 AWG wire. When wiring multiple
units, each unit’s wiring must conform to the above.
5.7.2 Combination Control System Setup and Startup
Setup for the Combination Mode requires entries to be made in the Configuration Menu for
boiler mode, remote signal type and setpoint. The setpoint is adjustable from 40°F to 190°F.
Enter the following settings in the Configuration Menu:
Menu Option Setting
Boiler Mode Combination
Remote Signal Network
Internal Setpt 40°F to 190°F
Refer to section 3.3 for instructions on changing menu options.
While it is possible to change other temperature-related functions for combination mode, these
functions are preset to their factory default values. These default settings work well in most
applications. It is suggested that AERCO be contacted prior to changing settings other than the
unit’s setpoint. For a complete listing of temperature related function defaults, see Appendix D.
To set the unit to the manual mode, press the AUTO/MAN switch. The MANUAL LED will light.
To set the unit back to the auto mode, press the AUTO/MAN switch. The MANUAL LED will go
off and the REMOTE LED will light.
When the boiler is switched to ACS control, the ACS controls the valve position. There are no
setup requirements to the boiler(s) in this mode.