Trane TRG-TRC016-EN manual Water-Cooled Absorption Chillers, Chiller type Capacity

period one

Types of Water Chillers

notes

Note: Addendum J updates the minimum IPLV efficiency requirements in the standard to match the methods included in the most current version of the ARI rating standard. At the time this booklet was printed, Addendum J had not been formally adopted as part of the standard. However, its adoption was deemed sure enough to include in this publication.

The standard requires that both full- and part-load conditions be met. For example, the efficiency of a water-cooled centrifugal chiller with a capacity greater than 300 tons [1,056 kW] must be 6.1 COP, or better, at ARI standard conditions. This is equivalent to 0.576 kW/ton. The part-load (IPLV) efficiency must also be 6.4 (based on the efficiency units of COP) or better. This is equivalent to an IPLV of 0.549 kW/ton.

Coefficient of performance (COP) is a unitless expression of efficiency, defined as useful energy out divided by energy input. A higher COP designates a higher efficiency.

3.516 kW/ton = --------------

COP

standard 90.1-1999 efficiency requirements

Water-Cooled Absorption Chillers

chiller type	capacity	minimum efficiency*
single-effect	all capacities	0.7	COP
double-effect
indirect-fired	all capacities	1.0	COP	1.05 IPLV

direct-fired

all capacities

1.0 COP 1.0 IPLV

* as of October 29, 2001

Figure 28

The table in Figure 28 includes the minimum efficiency requirements for absorption water chillers. For an absorption chiller, COP is defined as evaporator cooling capacity divided by the heat energy required by the generator, excluding the electrical energy needed to operate the pumps, purge, and controls.

Again, these minimum efficiency requirements take effect on October 29, 2001. The test procedure for these chillers is ARI Standard 560–1992. Note that the efficiency requirement for single-effect absorption chillers is higher than many manufacturers have offered in the past.

Section 6.3.4 of Standard 90.1 includes additional requirements for the design and operation of chilled-water systems. These requirements will be mentioned in later periods.

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