Standard for Fans and Blowers

ARI Standard 670: Essential Guide to Fans and Blowers

Selecting and specifying fans and blowers is a critical aspect of mechanical engineering design, directly impacting system efficiency, performance, and occupant comfort. For professionals working with HVAC systems, industrial ventilation, and building services, understanding the governing standards is paramount. ARI Standard 670, "Standard for Fans and Blowers," provides an authoritative framework for the testing, rating, and marking of these essential air-moving devices, ensuring consistency and reliability across the industry.

What is ARI Standard 670?

ARI Standard 670, published by the Air-Conditioning and Refrigeration Institute (ARI), establishes definitive requirements for factory-made fans and blowers. Its primary purpose is to provide industry professionals with clear definitions, standardized testing methodologies, precise rating criteria, and essential data requirements for published performance specifications. This comprehensive standard ensures that engineers and designers can confidently select and apply fans and blowers based on consistent and verifiable performance data.

Scope & Purpose

This industry-leading standard governs the testing and rating of factory-made components such as impellers, fans, and blowers. It defines various fan types, including axial flow (propeller, tubeaxial, vaneaxial) and centrifugal fans (scroll, transverse, tubular). Importantly, ARI Standard 670 excludes circulating fans like ceiling or desk fans, and large, high-horsepower fans typically tested in field installations per other ANSI/ASME standards. Its intent is to guide manufacturers, engineers, installers, and users towards best practices in fan and blower selection and application.

Who Must Comply?

• • Primary audience: Mechanical Engineers, HVAC Designers, Product Engineers, Test Technicians, and Compliance Officers involved in the design, manufacturing, or specification of air-moving equipment.
• • Industries affected: HVAC Manufacturing, Industrial Equipment Manufacturing, Building Systems Design and Integration, and related sectors.
• • Compliance nature: Voluntary, but highly recommended for manufacturers seeking to demonstrate product quality and performance consistency. Compliance is often a de facto requirement for participation in industry bidding and specification processes.
• • Enforcement: While ARI is a trade association, compliance is typically self-policed by manufacturers and verified by specifiers and end-users through adherence to published ratings and performance claims.

Key Requirements Overview

The standard requires that fans and blowers be tested according to recognized industry methods, such as ANSI/ASHRAE 51-1985 (ANSI/AMCA 210-85). Professionals must ensure that published ratings are expressed in terms of air quantity (cfm), static pressure (in. of H2O), fan speed (rpm), and power required at the fan shaft (hp) under specified rating conditions. Key provisions include clear definitions of standard air and various fan types, as well as outlining minimum data requirements for published ratings, ensuring transparency and comparability. Furthermore, the standard dictates tolerances for published ratings, ensuring that actual performance does not deviate significantly from specified values, typically within a 5% margin for speed and power.

Related Standards & References

ARI Standard 670 often works in conjunction with other foundational documents. It references standards like ANSI/ASHRAE 51-1985 (ANSI/AMCA 210-85) for standardized testing procedures, providing a robust methodology for performance