- Q.My questions have to do with
existing ungrounded circuits in older homes. My
understanding is that you should always replace
worn-out two-slot receptacles with new two-slot
receptacles (although they’re not always easy
to find). However, I’ve also been told that in
some locales you can install a three-prong receptacle
in an ungrounded circuit as long as you fill the ground
slot with epoxy. This is presumably to prevent someone
from using a grounded appliance on the ungrounded
circuit. What’s the code requirement, and what
about this epoxy business?
A.Redwood Kardon
responds: In my jurisdiction (Oakland,
Calif.), two-slot receptacles are readily available
and must be maintained on existing ungrounded
receptacles, unless the outlet is upgraded with a
ground per the NEC. The "epoxy business" sounds
funky to me. It is not an acceptable practice where
I work, and there is certainly no such "fix" in the
NEC. This issue most often surfaces when someone
wants to install a dedicated computer outlet. In
that case, a separate ground may be run, as noted
above, and a three-prong outlet
installed.
Redwood Kardon is a code
official in Oakland, Calif. For more code-related
information, visit his Web page at
www.CodeCheck.com.