National Electrical Installation Standards

Standards as High as Your Own

Tuesday, October 23, 2018


We hang three unit heaters there are ten feet in the air where do you put the service switch? We install them on the unit. They want me to put the service switch on the wall down at six feet off the floor and 30 feet from the heater is this right?

Bruce Henretty



Hey Bruce thanks for your question. If I understand the situation correctly then yes, it is acceptable. In general, disconnecting means must be installed within sight from fixed electric space heating equipment as stated in 424.19. There are special provisions in that section depending on supplementary overcurrent protection and the motor size. Based on the definitions of readily accessible (Accessible, Readily) and In Sight From if the switch is visible and within 50 feet from the unit heater it is OK.

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