GFCI rule for outdoor HVAC equipment to hit over 20 states

A National Electrical Code (NEC) requirement affecting outdoor HVAC equipment is set to take effect in more than 20 states on Tuesday, as ACCA and AHRI continue to push for a delay. 

Catch up quick: Before 2020, GFCI protection was not required for outdoor condenser connections. But in the 2020 NEC, the National Fire Protection Association (NFPA), which publishes the code, included a GFCI protection requirement for outdoor air conditioners and heat pumps.

• “Problems surfaced almost immediately,” Wes Davis, director of technical services at ACCA, told Homepros in July, as homeowners and contractors began reporting GFCI breakers tripping when ACs ran, “due to incompatibility with the equipment.”
• In August 2022, following an appeal led by ACCA and AHRI and backed by the National Association of Home Builders, the NFPA exempted outdoor HVAC equipment from the requirement until September 1, 2026 — an exemption that carried into the 2023 and 2026 editions. (A new NEC edition is published every three years.)

What’s happening: Earlier this month, Homepros reported that AHRI had submitted a Tentative Interim Amendment (TIA) to the NFPA, requesting it delay that deadline by two additional years, to September 1, 2028.

• The association’s request cited its own research, which found that nuisance tripping primarily stems from the interaction between inverter-driven equipment and individual GFCI devices, explaining why the same HVAC system may trip one breaker but not another and indicating that a universal fix is unlikely.
• ACCA has supported the move, noting that while the electrical industry has made progress in developing special high-frequency (HF) GFCI devices, “product development and listing alone fail to demonstrate that the interoperability problem has been resolved across the installed population of HVAC equipment.”

Driving the news: A definitive number of states in which the GFCI requirement will take effect on Tuesday couldn’t be ascertained, as state and local code regulations vary. A HARDI representative told Homepros that 24 states will be impacted, while an AHRI spokesperson placed the figure at 28 in some capacity — since in some states, only certain counties will be impacted. 

(Chart: NFPA)

Of note: States with an NEC edition from 2017 or prior, as well as states and localities that have independently exempted the requirement or deleted it outright, will not be impacted. 

• “NFPA tracks NEC enforcement throughout the United States and typically updates the information [quarterly]… However, NFPA does not maintain data on local amendments and therefore cannot determine which states will enforce all of the requirements,” an NFPA representative told Homepros. 

Looking ahead: AHRI’s TIA is in a public comment period until September 9, and the NFPA’s Standards Council is expected to rule on the amendment at its next meeting in December. 

• Yes, but: A source familiar with the situation told Homepros that the council may arrange a meeting on the TIA beforehand, though they didn’t specify when. 
• Between Tuesday and the council’s decision, state and/or local authorities will determine how to enforce the requirement.