AERCO BMK 2000DF - Manual (Page 33)

Benchmark 1500DF - 2000DF Boilers
CHAPTER 2 – INSTALLATION
OMM-0098_0A AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 Page 33 of 196
GF-144 Ph.: 800-526-0288 04/01/2014
In a ducted combustion air application, the combustion air ducting pressure losses must be
taken into account when calculating the total maximum allowable venting run. See the AERCO
Benchmark Venting and Combustion Air Guide, GF-2050. When using the unit in a ducted
combustion air configuration, each unit must have a minimum 8 inch diameter connection at the
unit.
2.14 SEQUENCING VALVE INSTALLATION
All Benchmark units are shipped with a connection for an optional motorized external
sequencing valve (p/n 92084-TAB) included in the shipping container. This valve is an integral
component of the AERCO’s on-board Boiler Sequencing Technology (BST) solution. BST
allows sites with multiple boilers to have one boiler, acting as a “master” to manage the other
boilers at the site in such a way that the efficiency of the entire boiler array is maximized.
The implementation of BST, and the installation and use of this valve is optional. However, the
boiler is pre-wired to accept the sequencing valve. Installation consists of installing the
sequencing valve in the hot water outlet pipe, and then connecting it into the shell harness, as
described below.
1. Install the sequencing valve in the boiler’s hot water outlet pipe.
Figure 2-13: Sequencing Valve Installed
2. The boiler’s shell harness has one unused cable. One end of this cable is connected to
the DELAYED INTERLOCK IN terminals in the I/O board (see Figure 2-14) while the other
end contains a Molex connector with a jumper wire inserted in it (this jumper wire allows
units that do not have a sequencing valve to operate normally). Find the free end of this
cable inside the unit’s enclosure.
HOT WATER
OUTLET
SEQUENCING
VALVE