Attempting to install a new drop in stove which has 4 wires for 220V. How do I wire into a 3 wire system?

Answer 1

First a water pipe is not a legal or safe ground. Especially since many homes are plumbed with plastic water pipes. It was common practice at one time and it had to be a cold water not hot pipe.
Since your existing wireing is 3 wire it was installed before 1996 when the code was changed to 4 wire for 220V.
In 3 wire you have 2 hot, either black or black and a red. and a neutral usually white.
4 wire has 2 hot, neutral and ground. ground will be green or bare wire. Ideally you would pull a fourth wire and change the outlet. Not hard if you use an existing wire as a pull wire though it might take some muscle to pull it past any bends in the conduit.
The white and ground are electrically conected inside the electrical panel, often to the same buss bar. In mine I have seperate buss bars but they are connected together.
It is not required to change to 4 wire unless you are moving the outlet. Because of this you can change the cord to 3 prong, the cord is available at home centers. if you do you will connect the white and ground from the stove to the neutral wire in the cord. I do not recomend this I only tell you what is commonly done. DO NOT replace the outlet with a 4 prong unles you pull the fourth wire. This is illegal and potentially unsafe as anyone would assume it has the fourth wire.
EDIT: I expect John ( top contributor and an electrician ) will be telling you to pull the wire too.
Me, I'm an indusrtial electrician not a contractor.

Answer 2

Charles C gave an excellent and detailed answer.

The electric code changed to require 4 wires on these circuits instead of the old way of using 3 wires. A 4 wire circuit is safer than the 3 wire circuit. That said, the three wire circuits worked for years with no problems. As Charles pointed out, the electric code is not retroactive. If you don't relocate or otherwise change the receptacle, you can still use it. If it was my house I would have an electrician (me) install a new 4 wire circuit and receptacle. As a second choice you could buy a 3 wire cord set that matches your existing receptacle and properly wire that to the stove. Be sure to do this correctly or have an electrician do it, so your stove is properly bonded and grounded. Feel free to email me if you need more help or advice with this.

The advice to connect to a water pipe is just plain stupid and shows a lack of understanding of basic wiring and electricity. Please don't do that.

Answer 3

The link provided by the fist poster is great, but it doesn't tell what to do if you don't have a 4 wire circuit with a separate bare ground wire. The best thing is to connect the ground from the new stove to a water pipe. Otherwise most people connect both the ground (bare) and the nuetral (white) together. Then you can hook up to your old 3 wire cable.

Answer 4

here is a site for you to use it is a good one I just look at it I have done some of my own wiring in the past, but all ways looking for more info all the time.
any way just go to it and it will give you step by step for wiring your new stove.
good luck and don't blow up the house....
just kidding take care.
http://www.hammerzone.com/archives/elect/finish/receptacle/range/01/recessed.htm

Answer 5

the three cord plus floor coming from the mild to the swap, needs a FEED to the two switches! So, between the three wires ought to be linked to the feed. that must be the black cord. i believe that the white cord is between the swap legs coming from between the switches. hence once you turn on the 2nd swap, the breaker pops. Take that white cord coming up from the swap container off of the team of whites interior the ceiling container and cap it.