Outlet Upgrade

[squintz1]

Hi everyone. I was just wondering if I could get some help with this. I would like to upgrade one of my wall outlets from the current 15A to 20A lines for my home theater setup. How do I go about doing this? It's not as simple as swapping the 15A circuit breaker for a 20A one is it?

Thanks!

B

[LazyPup]

Absolute DO NOT ever increase the size of a breaker or fuse.

The ampacity of a circuit is determined by the size and type of wire from which the circuit is constructed. A breaker or fuse is then selected to allow the maximum current that wire is capable of supplying without overloading. Increasing the size of a breaker, even slightly, will risk overloading the circuit and would then be a potential fire hazard.

When designing a circuit one has to consider all the loads that may ultimately be attached to that circuit. While a circuit may be rated at 15amps, that means it is only capable of safely supplying a combined load of 15amps. Thus a 15amp circuit could supply 15 devices with a one amp load, or one device with a 15amp load, but in no case should the total combined load on the circuit exceed the safe amperage rating for the wire.

In most cases residential general lighting circuits (general lights and outlets) are constructed with American Wire Guage (AWG)) #14 wire which has a maximum working load of 15 amps. (The codes also limit the maximum lenght of a run. When the length of a run exceeds certain limits the ampacity of the wire must then be derated to compensate for the additional resistance of the wire.)

In order to safely create a 20amp circuit you would need to install AWG # 12.

You could run a separate awg #12 wire and 20amp rated outlet to create a dedicated outlet for your entertainment system, then you could safely install a 20Amp breaker.

If one were to arbitrarily increase the breaker size from 15amp to 20amp you would then be running the wire at 30% over its rated safety margin and would seriously risk a fire.

[squintz1]

Thank you Lazy Pup, I think you just saved me from setting my house on fire! Since, according to the labels on the breaker panel, most of my living room is wired to this one 15A circuit breaker, is there any way I could just move the one outlet that I will be using for my home theater to it's own 15A breaker?

Bryan

[LazyPup]

It cannot be done by moving breakers. The outlet in question is only one of many on a common cable feed from the breaker box and the breaker feeds the cable. In order to isolate an individual outlet you would have to disconnect it from the cable it is on, then supply it from a separate cable from the breaker box.

If you elect to install a separate cable to feed that particular outlet, you then have the option of using AWG 14 wire and feed it with a 15 amp breaker, or using the heavier AWG 12 wire and you could supply it with either a 15 or 20 amp breaker, depending upon what the anticipated load will be.

Properly when selecting a breaker, you first begin by deterining the total load on the circuit, then install wire and use a breaker equal to the load, or the next higher standard breaker. By example,,if your load were actually 13.5amps you would be correct in using AWG 14 or AWG 12 and using a 15amp breaker, which is the next higher trade standard breaker to meet the load, but you would not be justified in using a 20amp breaker.

AWG 14 is rated for 15 amps and permitted in residential wiring, while AWG 12 can be used on either 15 or 20 amp circuits. AWG 12 is the minimum wire size used in commercial wiring circuits of both 15 and 20 amps. In fact, when one considers the minimal difference in wire cost between AWG 14 and AWG 12, in my humble opinion, for safety sake AWG12 should be considered minimum in residential as well.