Standard for Performance Rating of Commercial and Industrial Unitary Air-Conditioning and Heat Pump Equipment

ARI Standard 340/360: Standard for Performance Rating of Commercial and Industrial Unitary Air-Conditioning and Heat Pump Equipment

For engineers and designers specifying commercial and industrial HVAC systems, understanding equipment performance is paramount. ARI Standard 340/360 provides the authoritative framework for evaluating and comparing the capabilities of unitary air-conditioning and heat pump equipment, ensuring reliable and efficient operation in demanding applications.

What is ARI Standard 340/360?

ARI Standard 340/360, developed by the Air-Conditioning and Refrigeration Institute (ARI), establishes comprehensive guidelines for the performance rating of commercial and industrial unitary air-conditioning and heat pump equipment. Its primary purpose is to define standardized testing procedures, rating methodologies, and data requirements, enabling consistent and accurate assessment of equipment capacity and energy efficiency.

Scope & Purpose

This essential standard governs the performance rating and certification of electrically operated, vapor compression unitary air-conditioning and heat pump equipment designed for commercial and industrial use. Specifically, it applies to air-cooled, water-cooled, and evaporatively-cooled units with cooling capacities ranging from 65,000 Btu/h up to, but not including, 250,000 Btu/h. The standard explicitly excludes the rating and testing of individual assemblies (like standalone condensing units or coils) and equipment with capacities below the specified threshold or those employing different energy sources or technologies, such as water-source heat pumps.

Who Must Comply?

• • Primary audience: HVAC Engineers, Mechanical Engineers, Product Engineers, Testing Technicians, and Certification Specialists involved in the specification, design, manufacturing, and verification of HVAC equipment.
• • Industries affected: HVAC Manufacturing, Building Construction, Commercial Real Estate, and Industrial Facilities Management.
• • Compliance nature: While the standard itself provides a framework for voluntary participation in ARI's certification program, compliance is often a de facto requirement for market acceptance and competitive positioning. Manufacturers seek certification to demonstrate adherence to proven industry practices.
• • Enforcement: Compliance is primarily ensured through the ARI Certification Program, which involves independent testing and verification by accredited laboratories.

Key Requirements Overview

The standard requires manufacturers to adhere to specific methodologies for testing and rating their unitary air-conditioning and heat pump equipment. Key provisions include:

• • Standardized Testing Conditions: Professionals must ensure equipment is tested under defined ARI Standard Rating Conditions for both cooling and heating modes to enable fair comparisons.
• • Capacity and Efficiency Metrics: The standard mandates the reporting of key performance metrics such as ARI Standard Rating Cooling Capacity, Energy Efficiency Ratio (EER), and Coefficient of Performance (COP) for heating.
• • Part-Load Performance Evaluation: It requires the calculation and reporting of Integrated Energy Efficiency Ratio (IEER) or Integrated Part-Load Value (IPLV) to assess equipment efficiency across various operating loads, crucial for optimizing energy consumption in real-world applications.
• • Minimum Data Requirements: Manufacturers must provide specified data on nameplates and in published literature, ensuring transparency and consistency for end-users and specifiers.
• • Operational and Conformance Criteria: The standard outlines specific operating requirements and conformance conditions that equipment must meet to achieve certified ratings.

Related Standards & References

ARI Standard 340/360 works in conjunction with other