ISO 16358-1:2013

Overview

ISO 16358-1:2013 - "Air-cooled air conditioners and air-to-air heat pumps - Testing and calculating methods for seasonal performance factors - Part 1: Cooling seasonal performance factor" - defines test procedures and calculation methods to determine the cooling seasonal performance factor (CSPF) and related indices for products covered by ISO 5151, ISO 13253 and ISO 15042. It is intended for marking, comparison and certification and uses the T1 rating conditions in the referenced standards. The standard explicitly excludes water-source or water-cooled equipment, portable units with condenser exhaust ducts, individual assemblies that are not complete refrigeration systems, and absorption-cycle equipment.

Key topics and technical requirements

• Scope and applicability
  • Applies to air‑cooled air conditioners and air‑to‑air heat pumps covered by ISO 5151, ISO 13253 and ISO 15042.
  • Uses T1 rating conditions by default but allows procedures to be applied at other temperatures.
• Test methods and conditions
  • Specifies additional tests beyond referenced standards and requires instrument accuracy per ISO 5151/13253/15042.
  • Defines mandatory test conditions (Table 1) for T1 moderate climate (for example: indoor DB 27 °C / WB 19 °C; outdoor DB 35 °C / WB 24 °C as referenced).
• Performance metrics and calculations
  • Defines CSPF (ratio of annual cooling removal to energy consumed) and TCSPF (includes inactive and disconnected modes).
  • Covers defined cooling load, outdoor temperature bin distributions, and how to integrate seasonal bin hours.
  • Addresses performance across capacity types: fixed-capacity, two-stage, multi-stage and variable-capacity units.
  • Includes part load factor (PLF) and degradation coefficient (CD) to account for cyclic operation and part-load cycling (Annex C normative).
• Documentation
  • Specifies required contents of the test report and provides informative annexes for figures, TCSPF calculation (Annex B), cyclic degradation testing (Annex C), and supplementary calculation methods (Annexes D and E).

Practical applications and who uses it

• Manufacturers: to rate and declare seasonal cooling performance for product datasheets and certification.
• Independent test laboratories: to perform standardized CSPF/TCSPF testing for compliance and comparison.
• Certification bodies and regulators: to set energy labelling, minimum performance standards and compliance testing.
• HVAC designers, energy consultants, and procurement specialists: to compare system efficiency on a seasonal basis for specification and lifecycle energy assessment.
• Building owners and asset managers: to select efficient air-cooled units and estimate seasonal energy consumption.

Related standards and keywords

• Related: ISO 5151, ISO 13253, ISO 15042 (testing and rating references); Part 2 (heating) and Part 3 (annual performance) are complementary.
• SEO keywords: ISO 16358-1, CSPF, TCSPF, cooling seasonal performance factor, air‑cooled air conditioners, air‑to‑air heat pumps, seasonal performance testing, HVAC efficiency standards.