Trane TRG-TRC007-EN Manuale Utente

TRG-TRC007-EN

61

period four

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.

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