Chiller sequencing strategy
Plant has three chillers of equal capacity. Currently staged purely on a fixed load percentage with long time delays, which works but doesn't feel efficient at shoulder-season loads. Interested in how others structure staging logic — load-based, efficiency-based, or a hybrid — and what lead/lag rotation approach has worked well in practice.
Manufacturer
Trane
Protocol
BACnet/IP
2 Answers
Demo Engineer · Energy Performance Engineer
AcceptedA hybrid approach tends to work best in practice: use load percentage as the primary stage/destage trigger but add a runtime-based lead/lag rotation so wear is distributed evenly, plus a minimum run and minimum off timer to prevent short-cycling near the staging threshold. Pure fixed-percentage staging with long delays, like you described, is usually the reason shoulder-season efficiency suffers.
19 upvotes · 2026-07-30
Demo Engineer · Controls Engineer
If your chillers report kW/ton or similar, staging on plant efficiency rather than load percentage alone can squeeze out real savings at part load — worth checking if that data is already available before adding logic for it.
11 upvotes · 2026-07-31