Can I replace a 2-pole breaker feeding two branch circuits with two 1-pole AFCI’s?
No. The most common reason for a 2-pole circuit breaker feeding two branch circuits is the use of multi-wire branch circuits, also known as shared neutral wiring. This means that the two branch circuits use the same neutral conductor as a current return path to the loadcenter or panelboard. In these cases, a 2-pole AFCI, such as the Siemens Q215AF, should be used to replace the 2 pole conventional breaker. Two 1-pole AFCI’s cannot be used with this wiring method. If separate neutral wires exist for both branch circuits, then two 1-pole AFCI’s can be used. Each branch circuit load conductor and its corresponding neutral conductor must be connected to the same AFCI for proper operation.