period four

Equipment Sound Rating

notes

ARI Standard 260

IUses reverberant- room method

ITests entire air handler, not just fan

IAll common configurations and components included

IIncludes effects of secondary sound sources

Figure 66

The objective of ARI Standard 260–2001, Sound Rating of Ducted Air Moving and Conditioning Equipment, is to deliver sound data that accurately represents the acoustical impact of the air-handling equipment after it is installed.

This standard uses the reverberant-room method to measure the sound generated by the entire air handler, not just the fan. As mentioned, a fan performs differently inside an air handler than it does in a stand-alone application. The air-handler casing generally changes the airflow patterns at the fan inlet and discharge openings. This effect is the major reason for the difference between fan-only sound data and the actual sound produced by the air handler after it is installed.

To eliminate such inaccuracies, ARI 260 requires that the entire air handler be tested in all of the configurations in which the equipment is commonly applied in the field. This involves the four test configurations discussed in Figure 64, as well as various combinations of options such as inlet and discharge plenums, different types of filters, dampers, coils, and so forth.

Unlike the other methods, ARI 260 requires that secondary sound sources, such as return or exhaust fans and compressors, be tested to determine their acoustical impact on the air handler. Any secondary source that alters the sound spectrum of the supply fan must be included in cataloged ratings.

In summary, ARI 260 addresses a wide range of air-handling equipment with a consistent test method. It ensures accurate, verifiable sound data, and focuses on the entire air handler in all of its common installation arrangements. ARI 260 enables designers to make equitable product comparisons, and to more accurately predict sound-pressure levels for occupied spaces.

TRG-TRC007-EN

61

Page 68
Image 68
Trane TRG-TRC007-EN manual ARI Standard