Code Change Summary: Protection requirements for room air conditioners have been expanded.

Each new code cycle brings changes that may affect one group more than another. Some code changes have a direct effect on electrician while others may have more of an impact on the manufacturer, listing agency, or design engineer. There are many eyes on the NEC^®.

In the 2017 NEC^®, a change occurred for proper protection of room air conditioners that will mostly affect the equipment manufacturers. In this case, it provides one additional option for code compliance where only two existed before.

For the 2017 NEC^®, single-phase cord- and plug-connected room air conditioners now have 3 options for protection devices. Whichever is used, it must be factory installed and must be an integral part of the attachment plug or be located in the power supply cord within 12 inches of the attachment plug:

• Leakage-current detector-interrupter (LCDI)
• Arc-fault circuit interrupter (AFCI)
• Heat detecting circuit interrupter (HDCI)

All of the above options provide an extra measure of protection that is far more sensitive than just the overcurrent device where the branch circuit originates.

Cord- and plug-connected room air conditioners are often moved from one room to another or removed for the season and reinstalled again when needed. The abuse on the cord can often lead to insulation failure which ultimately becomes a potential shock hazard.

The heat detecting circuit interrupter (HDCI) is a recently new protection device. According to the UL guide information (KFGP2), the HDCI incorporates all of the protective functions of an LCDI but also incorporates a thermal detection ability which provides additional protection against overheating of the air conditioner’s compressor.

Below is a preview of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC^® edition of NFPA 70.