Installing new 220v line

I have an air compressor that I have not been able to use because it requires 220v and all the circuits in my breaker panel are 110v. On my electric bill in states that I have 220v service but I can not figure out how to connect it. I had four 15 amp breakers which I replaced with "two-in-one" 15 amp breakers and they work great. The clerk at the Lowe's also sold me a "double-gang" 30 amp breaker. When I put in the "double-gang" breaker I tried to measure the voltage between the breaker terminals and there was no voltage. I still get 110v between the breaker terminal and neutral. I plan on using 10-3 Romex with a seperate ground wire. I understand that I need to connect the black and red wires to the "double-gang" breaker but I am not getting a voltage reading there.

What am I doing wrong?

Also, the only receptacle they had that would work with my compressor's power cord only has two line connections and the ground connection.

What do I do with the white wire?

Any help would be appreciated.

 

If the clerk sold you a 2 pole breaker, then the measurement between terminals are 220-240V. If he sold you a twin breaker (two 1 pole breakers in the size of one full size breaker), then the measurement is 0V between terminals and you need to bring it back.

Your compressor doesn't need the neutral, so don't connect it on either end and fold it back into the box for future use.

 

Also, what brand of panel do you have? On Federals you can install a double pole and be on the same leg. You need to straddle the little plastic divider. I have ran into that a couple of times. I am not sure about any other brands of panels that would allow that to be done. Ron, I am almost sure he didnt get a tandem breaker. Have you ever seen a tandem 30? I dont think you would find one at Lowes. That would be a mighty dangerous piece of equipment in the wrong hands. Another thing, the air comp only uses 2 working wires and requires only 10/2 wg. If you use the 10/3 cap off the white wire and leave it unused.

 

Ok. I looked again and its a double gang 20-amp. I found the divider that you mentioned and it is directly between the six slots, three on each side. I placed the double gang breaker in the center so that it straddled the divider. Now I have 220v.

Also, I remember now the saleman told me I needed the 10-3 so that I had a black and a red wire and to tape-off the white wire.

I am looking back at this and wondering why I even tried this myself. Next is a new roof!

David

 

I just read in another thread that a permit is required for all electrical work. The only thing I have done so far is shuffled the breakers around. The wire will be running up the inside of the wall from the breaker box then through the attic to the attached garage. I was told that I do not need conduit for the Romex wire I purchased. Should I get a permit before I run the wire?

 

The compressor is straight 220v. It has no 120 components. You could have done the job with 10/2. You mark the white wire black with tape or a marker.

 

I just stopped by the Lowes and looked at the 10/2 wire and it is much more flexible. I will be trading in my 10/3 mainly for the easier installation. Of course, I can can also color the white wire red, right?

Also, I have never even talked to my city's planning department for anything before. Such as when I installed the four flourescent fixtures in my garage or when I ran a grounded circuit to my study for the computer. Will they allow me to do the electrical work myself if I apply for the permit? Is it required by law?

David

 

You can (and must) remark the terminations of that white wire in any color you want except for gray or green. Red's a good color.

In most areas, someone who owns and lives in a house can do all the electrical work. Some areas require a licensed electricians. Some areas require the homeowner to pass a test first. Check with your building department.

 

depending on the current draw of the comp you can use a number 12 wire on that line.