Advanced User Guide

Part number 550-100-160/0715
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Figure 26 Evergreen sequencing options — SMART, PARALLEL or SERIES (examples shown for 3-boiler network)
SERIES Sequencing PARALLEL Sequencing SMART Sequencing
Higher Part-Load Efficiency
Quicker Boiler Response Time
STAGE 1 – Lead boiler modulates up to a maximum of 100% be-
fore turning on the next boiler in the sequence. The STABILIZE
4)-%ALLOWSTIMEFORTHEBOILERSTOMODULATETOMEETSYSTEM
demand before turning on additional boilers.
STAGE 1 – Lead boiler modulates up to a maximum of Base
Rate High before turning on the next boiler in the sequence.
4HE34!"),):%4)-%ALLOWSTIMEFORTHEBOILERSTOMODULATE
to meet system demand before turning on additional boilers.
STAGE 1 – Lead boiler modulates up to a low firing rate before
TURNINGONTHENEXTBOILERINTHESEQUENCE4HE34!"),):%4)-%
allows time for the boilers to modulate to meet system demand
before turning on additional boilers.
STAGE 2 – Boiler #2 in sequence ignites and both boilers
modulate to so their combined energy output matches the energy
OUTPUTOF"OILERAT!FTERASHORT-/$$%,!94)-%
the boilers will be released to modulate.
STAGE 2 – Boiler #2 in sequence ignites and both boilers
modulate to so their combined energy output matches the energy
OUTPUTOF"OILERAT"ASE2ATE(IGH!FTERASHORT-/$$%,!9
4)-%THEBOILERSWILLBERELEASEDTOMODULATE
STAGE 2 – Boiler #2 in sequence ignites and both boilers modu-
LATETO"!3%2!4%,/7!FTERASHORT-/$$%,!94)-%THE
boilers will be released to modulate.
STAGE 3 – Both boilers modulate up to a maximum of 100% be-
fore turning on the next boiler in the sequence. The STABILIZE
4)-%ALLOWSTIMEFORTHEBOILERSTOMODULATETOMEETSYSTEM
demand before turning on additional boilers.
STAGE 3 – Both boilers modulate up to a maximum of Base
Rate High before turning on the next boiler in the sequence.
4HE34!"),):%4)-%ALLOWSTIMEFORTHEBOILERSTOMODULATE
to meet system demand before turning on additional boilers.
STAGE 3 – Both boilers modulate up to a low firing rate before
TURNINGONTHENEXTBOILERINTHESEQUENCE4HE34!"),):%4)-%
allows time for the boilers to modulate to meet system demand
before turning on additional boilers.
STAGE 4 – Boiler #3 in sequence ignites and then all boilers
modulate to so their combined energy output matches the energy
OUTPUTOF"OILERSANDAT!FTERASHORT-/$$%,!9
4)-%THEBOILERSWILLBERELEASEDTOMODULATE
STAGE 4 – Boiler #3 in sequence ignites and then all boilers
modulate to so their combined energy output matches the energy
OUTPUTOF"OILERSANDAT"ASE2ATE(IGH!FTERASHORT-/$
$%,!94)-%THEBOILERSWILLBERELEASEDTOMODULATE
STAGE 4 – Boiler #3 in sequence ignites and then all boilers
MODULATETO"!3%2!4%,/7!FTERASHORT-/$$%,!94)-%
the boilers will be released to modulate.
STAGE 5 – After all available boilers are firing, boilers are release
to modulate up to 100% of rate.
STAGE 5 – After all available boilers are firing, boilers are release
to modulate up to 100% of rate.
STAGE 5 – After all available boilers are firing, boilers are release
to modulate up to 100% of rate.
CONDENSING GAS BOILER — Advanced Manual
™
ROTATION AND SEQUENCE (continued)