Code Q&A: Disconnect Rules for Fixed Electric Space-Heating Equipment

June 4, 2020

Test your NEC knowledge.

Based on the 2017 NEC.

Q. What is the Code rule regarding disconnects for fixed electric space-heating equipment?

A. Means must be provided to simultaneously disconnect the heater, motor controller, and supplementary overcurrent protection devices of all fixed electric space-heating equipment from all ungrounded conductors [Sec. 424.19].

Heating equipment without supplementary overcurrent protection ― For fixed electric space-heating equipment, the branch-circuit circuit breaker can serve as the disconnect if the circuit breaker is within sight from the heater or it’s capable of being locked in the open position [Sec. 424.19(B)].

Unit switch as disconnect ― A unit switch with a marked “OFF” position that’s an integral part of the equipment can serve as the heater disconnect, if it disconnects all ungrounded conductors of the circuit [Sec. 424.19(C)] (Figure 424.19C0 01).

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.