# Can I replace a 30 amp breaker with a 40 amp breaker?

**breaker**protects you from excess current flowing through the system. Installing a 40A

**breaker**raises the ceiling on the allowed current. You just swap out a 30A

**breaker**with a 40A

**breaker**. You're allowing the electrical system (not just the

**breaker**) to run at 33% over it's rated capacity.

Then, can I replace a 20 amp breaker with a 40 amp breaker?

Different question and the answer is "It depends". But in general the answer is "No, **do** not go and put a 30 **amp breaker** in place of a **20 amp breaker** because the wiring is most likely 'sized' for the **20 amp** load and -may- overheat if a 30 **amp** load is used with wiring sized for a **20 amp** load."

**30**-

**amp**outlet supplies 3,600 watts (

**30 amps**multiplied by 120 volts). Therefore, the

**breaker**on that outlet

**could**meet code and still trip anywhere between a total load of 2,880 watts (80 percent of 3,600 watts) and 4,320 watts (120 percent of 3,600 watts).

Consequently, can I replace a 30 amp breaker with a 50 amp breaker?

**30 amp** circuits use a 10 gauge wire, while **50 amp** circuits require larger 8 gauge wire. Consult with your local building department or a licensed electrical contractor before making the **change**. Better to be safe than sorry, a overload on a circuit that powerful **can** cause a major fire.

No! The only safe way to increase the **circuit's** capacity is by replacing the wire with one of adequate gauge. For 20 **amps**, 12 AWG copper is adequate for up to about 100 feet. If you simply replace the **breaker**, the wire **can** overheat and ignite the building from inside the walls.