The Air Conditioning Contractors of America (ACCA) has appealed the National Fire Protection Association’s (NFPA) decision to reject Tentative Interim Amendment (TIA) 1924, which would extend Exception No. 2 to Section 210.8(F) through September 1, 2028.
ACCA supports GFCI protection that provides electrical safety without unnecessarily shutting down HVAC equipment. Before a national requirement is imposed across outdoor HVAC systems, there should be adequate evidence that available GFCI technology is compatible with the equipment it is required to protect. In extreme heat, an unintended loss of cooling can itself create a serious safety risk, particularly for vulnerable occupants.
Why ACCA appealed
ACCA supported the extension because significant questions remain about equipment compatibility, nuisance tripping, product availability, field enforcement, and whether newer GFCI technology has been sufficiently validated across the range of HVAC equipment covered by Section 210.8(F).
The recent availability of high-frequency (HF) GFCI products is important progress. But availability alone does not demonstrate reliable compatibility. Proof is needed that includes field and laboratory testing of both inverter-driven and single-stage HVAC equipment. A solution aimed at high-frequency leakage associated with inverter technology does not necessarily resolve nuisance-tripping concerns at 60 Hz or establish universal compatibility.
Where is the compatibility evidence?
AHRI’s research examined the GFCI technology and HVAC equipment involved in the compatibility problem. ACCA’s appeal raises the next practical question: where is the comparable testing and field evidence demonstrating that the newer GFCI technology resolves those problems across the equipment now subject to Section 210.8(F)?
ACCA has asked the NFPA Standards Council to consider whether sufficient additional testing and field data have been developed to show that the compatibility problem has been solved. The goal is straightforward: a GFCI requirement that provides the intended electrical protection and works reliably with the HVAC equipment connected to it.
A closely divided decision
NEC Code-Making Panel 2 (CMP-2) rejected TIA 1924 on both technical merit and emergency nature. On technical merit, the panel vote was evenly divided, 10-10; approval requires the necessary NFPA ballot threshold. The NEC Correlating Committee approved the TIA on correlation, and AHRI reports that 90 percent of the 30 public comments submitted on the proposal supported it.
AHRI has also appealed. Its appeal raises procedural concerns about the processing of TIA 1924, including NFPA staff’s request that AHRI seek resolution with GFCI manufacturers before the TIA proceeded through the NFPA process. ACCA’s appeal concentrates on the unresolved technical, safety, and field-implementation questions facing contractors.
Contractors and inspectors need a workable requirement
Section 210.8(F) has already received differing treatment among states and local jurisdictions, including modification, delayed enforcement, or deletion of the requirement. For contractors working across jurisdictions, that creates significantly different requirements for similar HVAC installations.
An authority having jurisdiction also cannot necessarily determine from an installation whether a particular system will exhibit leakage-current characteristics associated with an inverter product, a single-stage product, or another design. Code requirements need to be both technically supported and practical to enforce in the field.
The code and product standards are still evolving
ACCA also identified a disconnect between terminology in the 2026 NEC and the UL 943 product standard. The significance for contractors and inspectors is practical: the Code should point to protective technology that actually exists in the product-standard framework and can be readily identified and applied in the field. Activity in the next NEC revision cycle is already addressing this issue, another indication that the code-and-product-standard framework continues to evolve.
The requirement is here – and the appeal continues
Exception No. 2 has expired, so contractors now face the Section 210.8(F) requirement while the appeals process moves forward. ACCA has requested that the Standards Council approve TIA 1924 and extend the exception through September 1, 2028. ACCA has also requested a hearing.
The requested extension is not a rejection of GFCI protection as a safety objective. It is a limited extension intended to allow compatibility validation, product-standard work, code development, and field implementation issues to be resolved.
ACCA will continue coordinating with industry stakeholders, supporting contractors as jurisdictions address the requirement, and updating members as the Standards Council process moves forward.
For background, technical resources, continuing updates, and information contractors can use in their jurisdictions, visit ACCA’s GFCI Resource Page.
For more information please contact David Bixby, ACCA’s manager of codes at david.bixby@acca.org.
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