Furnace Circuit Breaker Size

Because of the lower amperage rating of the 30 amp circuit of the new furnace the existing 60 amp circuit that will be connected to the 30 amp circuit should be changed to the 30 amp rating.

Furnace circuit breaker size.

The furnace uses the power. A 30a circuit breaker can safely carry the exact 30a current but nec suggests 80 as a safe current limit as compared to the rated current. This will provide the necessary overload protection for the circuit wiring and internal furnace components that are part of that 30 amp circuit. By multiplying the volts by amps you will receive total wattage.

The blower and control circuit for a modern gas furnace uses its own 110 to 125 volt circuit breaker. The best thing you can do is check the nameplate on the furnance where you will find the power and breaker requirements for your specific unit. However typically electric furnaces require a draw between 60 and 80 amps. The size of a breaker is determined by the amp draw.

Difference between circuit breaker and isolator disconnector circuit breaker size calculation for continuous non contentious load. The residential gas furnace needs power only to run the motor so it usually needs a 15a breaker if it doesn t share the circuit with other consumers in the home. As circuit breakers cbs and overcurrent protection devices ocpd are designed for 100 rated current i e. A single sheathed cable runs from the circuit breaker to a single pole light switch located next to the furnace.