## NA7.13 Compressed Air System Acceptance Tests

### NA7.13.1 Construction Inspection

Prior to functional testing, a compressed air system must verify and document the following:

(a) Size (hp), rated capacity (acfm), and control type of each air compressor

(b) Total online system capacity (the sum of the individual capacities)

(c) System operating pressure

(d) Compressor(s) designated as trim compressors

(e) Method for observing and recording the states of each compressor in the system, which shall include at least the following states:

Off

Unloaded

Partially loaded

Fully loaded

Short cycling (loading and unloading more often than once per minute)

Blow off (venting compressed air at the compressor itself)

### NA7.13.2 Functional Testing

Step 1: As specified by the test methods outlined in the Construction Inspection, verify that these methods have been employed, so that the states of the compressors and the current air demand (as measured by a flow sensor or otherwise inferred by system measurements) can be observed and recorded during testing.

Step 2: Run the compressed air supply system steadily at as close to the expected operational load range as can be practically implemented, for a duration of at least 10 minutes.

Step 3: Observe and record the states of each compressor and the current air demand during the test.

Step 4: Confirm that the combinations of compressors states meet the following criteria:

(a) No compressor exhibits short-cycling (loading and unloading more often than once per minute).

(b) No compressor exhibits blowoff (venting compressed air at the compressor itself).

(c) For new systems, the trim compressors shall be the only compressors partially loaded, while the base compressors will either be fully loaded or off by the end of the test.