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    koolkat99's Avatar
    koolkat99 Posts: 4, Reputation: 1
    New Member

    Feb 21, 2008, 01:45 PM
    Replacing 2-prong receptacle with 3-Prong -NO GROUND WIRE
    Hi there! I was wondering if someone can tell me how exactly I go about doing this safely. I have an existing 2 prong ungrounded plug... theres no ground to this receptacle... old metal box does not seem to be grounded either. I would like to replace this receptacle with a 3 prong GFCI receptacle, and add 2 additional receptacles on this circuit. The room is a bedroom and the load on the circuit would be a lamp and computer/peripherals. I need something to protect my computer in the case of a power surge. I know I can connect all the receptacles ignoring the ground wire on the downstream receptacles and label the receptacles non grounded GFCI, however, I really would prefer an easy way to actually make this circuit grounded. The light, switch, other receptacle in the room are grounded with new wiring... this is the only one in the house that is still knob & tube. I can't add additional receptacles on the other grounded circuit as I fear the load will exceed 15 amps.

    What should I do and how? HELP!!
    KISS's Avatar
    KISS Posts: 12,510, Reputation: 839
    Uber Member

    Feb 21, 2008, 02:48 PM
    A GFCI is not a surge suppressor. GFCI's can be used without a ground, but they must be marked.
    AFCIs are required in bedrooms.
    There are combo AFCI/GFCI breake

    AFCI's protect against frayed cords etc.

    The surge suppressor won't be as effective without the ground.

    You have to run a new wire. Your not allowed to t run a ground. An AFCI breaker should be installed for the bedroom.
    hkstroud's Avatar
    hkstroud Posts: 11,929, Reputation: 899
    Home Improvement & Construction Expert

    Feb 21, 2008, 03:30 PM
    Your not allowed to jus t run a ground.

    I think there is an exception when replacing a two prong receptacle with a three prong, or there use to be, but I don't know. Will wait for expert.
    KISS's Avatar
    KISS Posts: 12,510, Reputation: 839
    Uber Member

    Feb 21, 2008, 03:37 PM
    You can replace a two prong with a GFCI without a ground as long as the outlets are labeled as such.

    But if you had 14/2 without a ground, your not allowed to add just a single ground wire. It must be replaced with 14/2 with ground.

    I don't think you can just add a ground to knob and tube, because your upgrading at this point.
    koolkat99's Avatar
    koolkat99 Posts: 4, Reputation: 1
    New Member

    Feb 22, 2008, 08:53 AM
    Thank you all for responding so fast! Agreed that I can't connect the ground of the 14/2 to the old wiring, as if there was a short anything connected to this receptacle and all the receptacles downstream would become "live". It is code with both NEC and CEC to replace 2 prong with 3 prong as long as its labelled as such. So basically, I should just replace the 2 prong to 3 prong gfci, label it as ungrounded gfci, but Im still worried that if I plug in a surge protector bar into this receptacle, that in the event of a power surge, the surge protector will become useless and my PC and other electronics will be damaged. Is there a way to get around this so that the surge protector will work? Its an old victorian house and it would be a huge job to bring a brand new wire from the breaker panel up to the third floor.

    Another thing I was thinking, the other receptacle in the room is new wiring and comes from the breaker (14/2), although there's a lot of load on this circuit (6 halogen potlights, 1 5 light halogen light fixture, 4 halogen spotlights, 2 40watt bulbs in the ceiling light, 3 receptacles and 1 microwave) can I somehow add more receptacles on it and change it to 20 amps as opposed to 15 amps just at the breaker?
    KISS's Avatar
    KISS Posts: 12,510, Reputation: 839
    Uber Member

    Feb 22, 2008, 09:28 AM
    You can replace the breaker only if the wiring is 12/2.

    Light bulb: Protection could be had, and no one would know, if you stole the ground from the other outlet externally. At least you would get the protection. Here is an idea:

    Get a decent surge supressor like the Isobar. It comes with a connected equipment warranty.

    Get a female portable cord connector, 3 prong and a cord that has a wide and narrow blade. If it's 3-wire cut off the third prong. Connect the Hot and Neutral to the female cord connector.

    Wire only a ground to the 3 prong plug, with it properly strain reliefed and plug that into a grounded outlet. Connect this ground to the 3 prong cord connector above.

    So your drawing power from the knob and tube and the ground from elsewhere.

    This way, the house wiring is correct. The surge suppressor won't be modified, so the warranty works.

    You make the decision.

    I don't recommend using a surge supressor with an RFI filter without the ground.
    hkstroud's Avatar
    hkstroud Posts: 11,929, Reputation: 899
    Home Improvement & Construction Expert

    Feb 22, 2008, 09:36 AM
    Suggest that you consider installing "whole house" surge protectors at the service entrance panel where you do have grounding . Note that these vary in cost and capabilities.

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