EB-NB Installation Manual

12/28/2018 26 BI804
Temperature limits information – there are three temperature sensing monitors which will control the
sequencer and electric elements.
 The control main control board, with its supply sensor, controls the stages to maintain a supply
temperature represented by system configuration. This sensing monitor and control applies to
outdoor reset or no outdoor reset.
 Auto reset limit, HL-2 – probe at the vessel top, fixed at 210° F (99° C), signals sequencer to shut
down (auto resets at approximately 195° F (90.5° C)).
 Primary safety limit, HL-1 – mounted on vessel top, fixed 225° F (107° C), manual reset (resets
at approximately 160° F (71° C)).
Stage sequencing – in normal operation there is a progressive stage up or stage down timing. The delay
between stages is not always the same, it depends upon the differential between existing and the next
stage command.
 The Electro Sequencer plug-in software chip has a version 1.** with a dash number. The dash
number must match the number of stages for the specific boiler unit model number (see
Specification Table, stage number). This should be verified to make sure your installation and
your specific model is setup for the correct maximum number of stages. This provides the correct
sequence and operation for the progressive stage-up/stage-down timing.
 During alarm conditions, there is only 1-second between stages.
 For test purposes the Electro sequencer can be setup to only have 1-second between stages. Next
to the J3 connector is a W1 test point wire. Simply jumper this test point wire to ground (do not
apply a voltage to W1) and all staging will now be 1-second for either up or down.