Standard for Water-Source Heat Pumps

ARI Standard 320-1998: Standard for Water-Source Heat Pumps

For engineers and designers navigating the complexities of HVAC systems, establishing reliable performance benchmarks is paramount. ARI Standard 320-1998, the Standard for Water-Source Heat Pumps, provides an essential framework for ensuring consistency, efficiency, and accurate performance ratings in this critical technology. This authoritative document is a cornerstone for professionals seeking to specify, design, and verify the performance of water-source heat pumps in a wide range of applications.

What is ARI Standard 320-1998?

ARI Standard 320-1998, developed by the Air-Conditioning and Refrigeration Institute (ARI), establishes comprehensive definitions, classifications, testing procedures, and performance requirements for water-source heat pumps. Its primary purpose is to provide a standardized methodology for rating the cooling and heating capacities, as well as energy efficiency, of these electrically driven, mechanical compression systems. This ensures that professionals can compare products from different manufacturers with confidence.

Scope & Purpose

This standard governs the factory-made residential, commercial, and industrial water-source heat pumps that utilize a common water loop for heat exchange. It specifically applies to electrically driven, mechanical compression type systems with cooling capacities rated below 135,000 Btu/h. The standard does not cover the rating or testing of individual components or assemblies intended for separate use, nor does it apply to systems not meeting the defined criteria for electrically driven, mechanical compression types.

Who Must Comply?

• • Primary audience: HVAC Engineers, Mechanical Designers, Product Engineers, Test Technicians, Installation Contractors, and Building Managers.
• • Industries affected: HVAC Manufacturing, Building Construction, Commercial Real Estate, and Industrial Facilities.
• • Compliance nature: Compliance with ARI standards is typically voluntary but becomes effectively mandatory for manufacturers seeking ARI certification and for engineers and specifiers who include certification as a requirement in their project documents.
• • Enforcement: Manufacturers voluntarily submit their products for testing and certification by ARI-recognized laboratories. Compliance is verified through rigorous testing against the standard's requirements.

Key Requirements Overview

The standard requires manufacturers to adhere to specific definitions for terms like Coefficient of Performance (COP) and Energy Efficiency Ratio (EER) to ensure clarity in reporting. Professionals must ensure that testing procedures align with ASHRAE Standard 37 and the specific methods outlined in ARI 320-1998 to obtain verified ratings. Key provisions include establishing standard rating conditions for both cooling and heating modes, ensuring accurate measurement of capacity and energy input. Furthermore, the standard mandates specific marking and nameplate data to clearly communicate performance characteristics to end-users and specifiers.

Related Standards & References

ARI Standard 320-1998 works in conjunction with other proven industry standards. ASHRAE Standard 37, "Methods of Testing for Rating,” provides the foundational procedures for conducting performance tests on air-conditioning and refrigeration equipment, which are adapted and specified within ARI 320-1998. Additionally, other ARI standards, such as ARI 325 and 330, may cover related equipment or alternative applications, ensuring a comprehensive approach to HVAC system design and specification across the industry.