sequencing chillers using Equipment Controls

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Hi All,

I'm using eQuest version 3.65 and am having trouble with sequencing my
chillers - I've combed through the archives but haven't found anything that
has helped.

I have 3 chillers in my model, a water-side economizing chiller and two
air-cooled scroll chillers. I would like to control them such that my WS
economizing chiller runs up to a certain capacity only (175 Tons = 2.1
MBtu/h). Without any controls, eQuest is ignoring the capacity I have
entered, and is meeting my building's entire cooling load. Beyond the 2.1
MBtu/h, I would like my 2 other chillers to run to meet the remaining load.

I've created an Equipment Control (and selected it on my CHW loop) that has
my WS Econo Chiller as sequence no. 1 with a max load of 2.1 (I believe
units of MBtu/h). Then I have my other chillers as sequence 2/3 and left
max loads as "999". I've played around with the "Max Load" values and also
the "Loads Through" value and nothing I do changes the outcome. Is anyone
able to help me figure out why eQuest is not capping my WS Econo Chiller at
the 2.1 MBtu/h and why it continues to meet the entire cooling load (with a
peak approaching 4 MBtu/h)?

Thank you in advance.

---
Chris Hadlock, M.A.Sc ., P.Eng, LEED AP BD+C
Founder & Senior Energy Consultant

HADLOCK CONSULTING
201 Candlewood Cr
Waterloo, ON N2L5T3
tel: (519) 804-1223
cel: (226) 343-5599
www.hadlockconsulting.ca

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