Den tillämpliga NEC-citat för en vanlig lufthanterare av denna typ är 424.19 (A) (2) (424.19 (A) (1) gäller inte för de flesta lufthanterare eftersom fläktmotor i dem är över 1/8 hk ):
424.19 Disconnecting Means. Means shall be provided to simultaneously disconnect the heater, motor controller(s), and supplementary overcurrent protective device(s) of all fixed electric space-heating equipment from all ungrounded conductors. Where heating equipment is supplied by more than one source, feeder, or branch circuit, the disconnecting means shall be grouped and marked. The disconnecting means specified in 424.19(A) and (B) shall have an ampere rating not less than 125 percent of the total load of the motors and the heaters and shall be lockable in accordance with 110.25.
(A) Heating Equipment with Supplementary Overcurrent Protection. The disconnecting means for fixed electric space-heating equipment with supplementary overcurrent protection shall be within sight from the supplementary overcurrent protective device(s), on the supply side of these devices, if fuses, and, in addition, shall comply with either 424.19(A)(1) or (A)(2).
(2) Heater Containing a Motor(s) Rated over 1/8 Horsepower. The above disconnecting means shall be permitted to serve as the required disconnecting means for both the motor controller(s) and heater under either of the following conditions:
(1) Where the disconnecting means is in sight from the motor controller(s) and the heater and complies with Part IX of Article 430.
(2) Where a motor(s) of more than 1/8 hp and the heater are provided with a single unit switch that complies with 422.34(A), (B), (C), or (D), the disconnecting means shall be permitted to be out of sight from the motor controller.
Med tanke på att motorstyrenheten i en luftbehandlare kommer att vara inuti luftbehandlaren (det är fläktreläet där), om inte din luftbehandlare har en brytare på utsidan för att fungera som avkopplingsmedel, behöver du en Motorrelaterade kopplingsorgan i sikte på luftbehandlaren. Ett icke-smältbart gjutet fall kopplas bort som det du länkade fungerar; du kan också använda en brytarebaserad "spa panel" -stoppsanslutning som den som används för luftkonditioneringsapparater, förutsatt att aktuell klassificering är lämplig, eller till och med en delpanel om du vill köra servicemannens kärl och whatnot av samma uppsättning ledningar som air handler.
Också, om du har en dörr på en skåp eller utklippslåda, bryter du inte "lättillgänglig" under 2017 NEC:
Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to actions such as to use tools (other than keys), to climb over or remove obstacles, or to resort to portable ladders, and so forth.
Note: Use of keys is a common practice under controlled or supervised conditions.