We need an outlet that needs to support 220v 27.4 amps. Ihave 2 120 lines at that location both with 20 amp breakers. Could I just use those lines connet them to the new outlet 2 hots and 1 ground. Then get a double poled breaker in place of the other 2 breakers. If so on the new dbl breaker should the breaker read 20 & 20 or 30 & 30. I gues I am not sure do you add 20 and 20 and get 40 or even know there are 2 20 amp breakers that combined breaker is still only 20 amps.

Thanks in advance

pattintom

From what I read, the answer is "no go!"

Sounds to me you need 30amps? If you do, then from what you said:

I have 2 120 lines at that location both with 20 amp breakers. this could mean that your present wires-- possibly 12AWG-- will not meet code requirements for a 30A circuit.

Also, are the two wires a straight run, or do they serve other loads (devices; equipment; etc.).

What are you installing that needs 220 volts @30A?

What is it for?
May need 2 #8's for hots, #10 for ground, and 40 amp breaker/2 Pole?
Should have specs or Nameplate?

What is it for?
Exactly!

Sorry, but the response of "Exactly" tells me nothing.

First, I am not an electrician and I immediately defer to those that are particularly with respect to code issues.

One step at a time, how do you know that the line is a 20 amp line? Are you using 20 amp outlets? Did you meter the amperage on the line coming out of the panel box?

My suggestions would be to use a single bar/double 60 Amp (27.4*1.5= 41.1 Amps) I've never seen a 45 or 50 amp breaker so you should go to a 60 Amp breaker and #6/3 cable, (Get a heavy cable cutter for this stuff). Black would go to one side of the double breaker. Red would go to the other side of the breaker. Neutral would go to the Neutral buss bar and the bare ground would go to the grounding bus bar.

Run the new cable and connect the properly rated outlet Red and Black to the power legs, neutral to neutral, ground to ground.

Are you planning to use this outlet outside the house? If so, you need to make sure you meet NEC Codes for out door outlets and if the outlet is going to service anything near water (pool) then you must use a GFCI outlet.

This question is a over a month old and I am closing the post to any additional posts.

Please do not answer questions or add to posts that are older than a month.