Code Change Summary: New requirements to address working space for an HVAC system disconnecting means.

On a new building, the HVAC installer and electrician often make penetrations through the exterior wall considerably close to one another to run the line set and associated wiring needed for the HVAC system. Sometimes very little thought is given to how the final installation of the outdoor condensing unit and associated disconnecting means will end up, or if sufficient working space will pe provided as required in the Mechanical Code and Electrical Code. Many such installations result in code violations and correction notices issued by the inspector that will hold up the final inspection.

Aside from a potential code violation, insufficient electrical equipment working space at an HVAC disconnecting means makes it unsafe to troubleshoot the system when necessary.

In the 2023 NEC^®, language was added in Section 440.14 which requires the disconnecting means for HVAC equipment to meet the working space requirements of NEC^® Section 110.26(A). The addition of this code language subsequently eliminated the need for informational note 2 which referred the code reader to see Section 110.26 in previous editions of the NEC^®.

Note that the new requirement is not triggered by whether or not the disconnecting means contains integral overcurrent protection.

Section 110.26(A) specifies the minimum required working space depth, width, and height dimensions for electrical equipment so that the worker can perform tasks safely. Keep in mind that the working space requirements in Section 110.26(A) apply to equipment operating at 1000 volts, or less to ground that is likely to require examination, adjustment, servicing, or maintenance while energized.

Working space height is measured from grade, floor, or platform to a height of 6-1/2 feet or the height of the equipment (whichever is higher). Within the working space height, other equipment associated with the electrical installation and located above or below the electrical equipment is permitted to extend not more than 6 inches beyond the front of the electrical equipment.

Some may argue that working space is not required for an HVAC disconnecting means because they feel that it is unlikely that the disconnecting means will be examined, adjusted, serviced, or maintained while energized, especially if the disconnecting means has no integral overcurrent devices but the first step for most service technicians coming out to troubleshoot an air conditioner is to open the disconnecting means to test for the presence of voltage on both the line and load terminals of the switch. If proper voltage is present on the load side of the switch, then the problem lies elsewhere.

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 2023 NEC^® edition of NFPA 70.