Replies

1. 
   Guest_ | Feb 23, 2000 01:30pm | #1

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   Frank,

   Most electric hot water heaters require 220 volts. Please check your water heater before you do any wireing. If it requires 220 it will not work on 110. All circuits must be protected by breakers or fuses. By definition, a subpanel is wired to the protected side of the main panel. Also, a subpanel generally supports multiple circuits. To wire a 220 subpanel you would need two vacant (adjacent) circuit breaker positions at your main panel. To wire a hot water circuit to your main panel you would also need two vacant breaker positions. So, if you have two vacant breaker positions you do not need a subpanel. You have a couple of options if all of your main panel breaker positions are dedicated (in use). You may be able to change out full sized breakers for slim line or duplex breakers and free up the positions you need for your 220 hot water heater circuit. This type of breaker is available for some but not all brands of panels. If you can not use slim line breakers you can wire a subpanel and divert 2 existing 110 circuits to it along with the new circuit for your water heater. I am concerned about the ability of your existing service to support the load of a hot water heater. If your service was sized with the assumption that you would have a gas hot water heater, particularly if you have an older house, your service capacity may be marginal. I very strongly suggest you get your hands on one of the do-it-yourself wiring books. With this resource you should be able to determine the adequacy of your service and its potential to support the load you are proposing to add and also the techniques to do this if you so desire. One question. Why electric? Take a look at the yellow stickers on hot water heaters at your home or plumbing supply store. Keeping gas will save you some big bucks.

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   Guest_ | Feb 23, 2000 03:47pm | #2

   *Frank,I read your question as "Can I use the 220 circuit which used to be for the water heater as a general 110 circuit.I'm not an electrician, but I believe the answer is "it depends."In my neck of the woods until recently water heaters were typically wired with 2 hots and 1 neutral, usually #10 cu and 30A breakers. (The 2 hots have to be from breakers which are next to each other to keep the phase of the 2 hots 180 degrees apart.)Wiring for subpanels under current practices calls for 4 leads from the main panel, 2 hots, 1 neutral, and 1 ground, with the neutral and ground buses in the sub being separated (not bonded together) So you probably shouldn't be using the existing wiring for a subpanel.Assuming the existing circuit breakers are 30A, the highest rated general purpose outlet I've seen is 20A, so you'd run the risk of overloading an outlet. (Say, trying to run 2 circular saws simultaneously off the one outlet.) Also, you'd have to change one of the existing hots to a ground.It _might_ be ok to convert 1 circuit breaker to a 20A, switch the other hot to a ground (geing sure to clearly mark the wire so converted) and leave the neutral as is.Practices and codes vary, howver, so you should check with a local electrician or code authority.Bob Walker

2. 
   G.LaLonde | Feb 23, 2000 07:08pm | #3

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   Frank, I read your question the same way Bob does, but I have some different advice. You probably now have a 240 volt line that fed your electric water heater. This consisted of 2 hot wires and a bare grounding wire. If you want to convert this to a 120 volt line you should disconnect it from the 2 pole circuit breaker in the service panel and replace that breaker with a single pole 20 amp breaker. Connect the black wire to the breaker screw and the white and bare wires to wherever the other white and bare wires are connected in the service panel. The other end of the wire near the heater should be connected to a GFCI (assuming this is a basement) receptacle as you would normally connect it. You could also add a few other circuits beyond this box as you would in normal house wiring. Don't forget to shut the power off in the main panel before you work on it!!

3. 
   Guest_ | Feb 24, 2000 10:16pm | #4

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   Well, my advise was good. Just need to find someone with the right question.

4. 
   CHARLES_CHRISTENSEN | Feb 25, 2000 04:21pm | #5

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   It should be pretty easy to switch a 220 circuit to a 120. I just installed four circuits for my power tools and the hardest part was installing the conduit and wires.

   In your case you will find two wires going from the water heater to a 220V breaker. Replace that breaker with a 120V breaker (it takes only one wire) and attach the second wire to the neutral bar in the breaker box. If both wires are black, do something to indicate the one wire is now a neutral like wrap some white tape at both ends. Make sure you get the same wire at both ends.

   An important thing will be to determine the gauge of the wire in this circuit. A 20A load can be carried by 12 gauge wire. If you have larger wire then no problem. If you have smaller wire then check a wiring chart for the max load you can use. Make sure the breaker matches or is less than the load that the wire and outlets will handle.

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   FrankS | Mar 02, 2000 08:16am | #6

   *SteveThanks for the helpFrankS

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   FrankS | Mar 02, 2000 08:19am | #7

   *Bob, G.LaLonde, Charles Forgot to thank you all, ThanksFrankS

5. 
   FrankS | Mar 02, 2000 08:19am | #8

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   I would like to change my water heater circuit (I have a gas one now) to 110v.
   Would it be OK to wire it to a subpanel with circuit breakers, or just tap off the 220.

   FrankS