Chillers

Copper can generate performance curves for all types of vapor-compression chillers. It handles two of the chiller models that are implemented in most common building energy simulation software tools; both models use performance curves that are function of the temperature of the water leaving the chiller and the part load ratio (ratio of load on the chiller to the operating chiller capacity). The main difference between the two models is that one uses performance curves that are function of the entering condenser temperature (referred to herein as the ECT model) and the other is function of the leaving condenser temperature (referred to herein as the LCT model). Additional documentation on the ECT model can be found in the EnergyPlus and DOE-2 engineering manuals; documentation on the LCT model can be found in the EnergyPlus engineering manual.

Chiller data library

The chiller library contains performance curves for existing chillers for both the ECT model and the LCT model. The number of performance curves for each compressor/condenser/model type varies; Table 1 provides a summary of the library.

Table 1 - Summary of the Chiller Library

Model	Compressor type	Condenser type	Compressor speed	Curve sets
ECT	centrifugal	air	constant	1
ECT	centrifugal	water	constant	95
ECT	centrifugal	water	variable	38
ECT	reciprocating	air	constant	1
ECT	reciprocating	water	constant	3
ECT	reciprocating	water	variable	1
ECT	screw	air	constant	9
ECT	screw	air	variable	11
ECT	screw	water	constant	38
ECT	screw	water	variable	4
ECT	scroll	air	constant	12
ECT	scroll	water	constant	7
LCT	centrifugal	air	constant	1
LCT	centrifugal	water	constant	95
LCT	centrifugal	water	variable	38
LCT	reciprocating	air	constant	1
LCT	reciprocating	water	constant	3
LCT	reciprocating	water	variable	1
LCT	screw	air	constant	9
LCT	screw	air	variable	11
LCT	screw	water	constant	38
LCT	screw	water	variable	4
LCT	scroll	air	constant	12
LCT	scroll	water	constant	7