Open grounds in three prong receptacles are a common issue found in older homes. This is an unsafe condition and should be corrected. The repair is fairly simple and does not require rewiring the home as some mistakenly believe. Only those circuits with the ungrounded receptacles are required to be addressed. This is usually no more than 3 or 4 circuits in a normal home.
The National Electrical Code allows three simple solutions.
Open Grounds are easy to make safe
First before we go any further, although this is a very simple procedure, if you are not familiar with electrical wiring this is best left to the professionals. This is for general information only; care must be taken to insure the proper materials are used and safety procedures are followed.
- Find the first receptacle in the string and replace it with a GFCI receptacle. This will provide GFCI protection to all receptacles on this line. Non grounded receptacles must be marked as “non-grounded GFCI protected”. A number of these stickers normally come with each GFCI receptacle.
- Locate the circuits involved and replace the current circuit breaker with a GFCI breaker, this will provide GFCI protection for all receptacles on this circuit. Non grounded receptacles must be marked as “non-grounded GFCI protected”. A number of these stickers normally come with each GFCI breaker.
- The least desirable solution is to replace ungrounded 3 prong receptacles with the old style 2 prong receptacles. This will meet code but will usually just result in the new owner replacing the 2 prong with 3 prong or worse yet using a 3 to 2 prong adapter.
- Another consideration for this method is that some city code officials will claim this is an upgrade and require the GFCI protection anyway.
The best solution for open grounds, if the breaker box is a newer style, would be to install the new dual purpose GFCI/AFCI breakers that provide both GFCI protection and AFCI (arc fault circuit interrupter).
The AFCI portion of the breaker protects against arcing in the wiring caused by any number of conditions. AFCI protection in new construction was first required for bedrooms in 2002, most other rooms in 2008 and as of 2014 GFCI and AFCI protection are both required in kitchens and utility rooms.