This practice may be employed for a relative determination of the useful energy collected by different solar collectors tested side-by-side under the same operating and environmental parameters, in the same location, and on the same test day. Variations in inlet temperature and transfer fluid flow rate should be minimized for best results.

Limitations: Caution should be exercised when comparing the all-day thermal performance data for collectors tested by this practice to the performance of other collectors not tested at the same time and the same location, or with the same test conditions. The data collected by this practice represent the behavior of the tested collectors only under the conditions occurring on the day of test and at the specific inlet temperature and fluid flow rate employed during the test.

5.2.1 In the case of low-temperature collectors (operating below 100°C (212°F)), consideration must be given to the relationship of inlet temperature to ambient temperature when analyzing or interpreting the test data.

Data collected in this test have not been shown to provide the overall comparison of collectors or collector concepts that would be required to support a nationally accepted rating or certification program.

1.1 This practice covers a means of generating all-day thermal performance data for flat-plate collectors, concentrating collectors, and tracking collectors.

1.2 The values stated in SI units are to be regarded as the standard. The values given in the parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.