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Re: [EnergyPlus_Support] Model a Chiller:Electric or Chiller:Electric:EIR

You created the CAPFT curve correctly.  And you used the correct chiller 
model since you have evaporator leaving water and condenser entering 
water temps. The fundamental equations are similar in the respective 
temperatures.

You should also create the EIRFT curve. You have both capacity and power 
in the data set. Calculate EIR as Power/Capacity, both in Watts (W/W or 
kW/kW). Then add this column to your spreadsheet (Actual EIR / Rated 
EIR). Use the rated EIR (1/COP = 19.5/ 80 = 0.2437) to normalize the 
data and also regress that data as you did before. Now you have 2 of the 
3 curves.

What I would do next is to look at the chiller output (search rdd file 
for "chiller" and find Chiller Evap Heat Trans Rate, Chiller Part Load 
Ratio,  and Chiller Cycling Ratio) and see if the data matches the 
manufacturers data. Look for the evaporator leaving water temperature 
and also the condenser leaving water temperature and see what the 
capacity is. You will need to divide the evaporator heat transfer rate 
(W) by the part-load ratio to get the actual operating capacity. If they 
match, then this is a good model. This comparison only works when 
Chiller Cycling Ratio = 1. Do the same for power.

If this all works well, then the only question is how well have you 
modeled the old chiller. You now know how to answer that question.



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