Overview
ISO 16358-1:2013/Amd 1:2019 is an amendment to ISO 16358-1 - the international method for testing and calculating cooling seasonal performance factors (CSPF) of air‑cooled air conditioners and air‑to‑air heat pumps. The amendment extends the original standard by introducing a standardized T3 (hot) climate test/calc path alongside the existing T1 (moderate) climate, updates symbols and formulas, refines test tolerances and cyclic test procedures, and adds Annex F with hot‑climate test conditions and bin distributions.
Key topics and technical requirements
- CSPF and TCSPF calculation: Methods for calculating Cooling Seasonal Performance Factor (CSPF) and Total CSPF (TCSPF) are maintained; Amendment 1 defines parallel calculation rules for T1 (moderate) and T3 (hot) climates.
- T3 climate test conditions (Annex F): Default test points, humidity settings and multipliers for hot climates are specified (e.g., 46 °C outdoor test condition and default relationships such as full/half/minimum capacity and power factors referenced to 35 °C tests).
- Outdoor temperature bin distribution: A reference bin table for T3 is provided (Table F.2) with a total reference cooling season of 6 493 hours; this supports seasonal weighting of performance across temperature bins.
- Symbols and formula updates: New symbols (e.g., CSE, Pful(46), ϕful(46)) and formula cross‑references added to support T3 calculations and consistency across fixed, two‑stage, multi‑stage and variable systems.
- Test procedure refinements: Cyclic cooling test conditions and durations now include separate tables for T1 and T3. Measurement tolerances were clarified (variation of individual dry‑bulb readings ±2.5 K; arithmetic mean ±1.5 K).
- Reporting requirement: Test reports must state whether the reported CSPF is for T1, T3, or a location‑specific bin distribution.
- Calculation tool: A spreadsheet tool is referenced to aid performance calculations (available from the ISO standards site).
Practical applications and users
- HVAC manufacturers validating seasonal efficiency for product datasheets and energy labeling.
- Accredited test laboratories conducting CSPF/TCSPF certification and compliance testing.
- Regulators and energy program administrators setting minimum efficiency requirements for moderate and hot climates.
- HVAC designers and specifiers comparing unit performance across climate zones.
- R&D engineers optimizing control strategies (e.g., staging, variable capacity) for seasonal energy efficiency.
Related standards
Keywords: ISO 16358-1:2013/Amd 1:2019, CSPF, TCSPF, air‑cooled air conditioners, air‑to‑air heat pumps, hot climate T3, testing and calculating methods, Annex F.