Jim Rooney On The Level

Q.I have a house in the mountains that I recently went to and found a mother raccoon with babies living in. She moved out with the pups that night and we sealed the chimney cap where she gained entry. Other than wrecking the place looking for food, water and general recreation it turns out there was water in the basement because the sump pump stopped.

There was no power to the pump so I flipped the breaker off & on and reset the GFCI outlet to the pump, and the pump came on. It ran fine until it evacuated all the water, but then it did not turn off, which was caused by a plastic disc holding up the pump float switch. The raccoon knocked this disc off a shelf into the sump pit apparently. After removing the disc, everything worked fine.

I was puzzled why the GFCI would trip and wondered if the pump running continuously would do that. My web search turned up a May 14, 2005 article by you where you say "Actually, your sump pump shouldn't be on a GFCI but rather on a dedicated non-GFCI outlet because sump pump motors can sometimes wreak havoc with GFCIs as can freezers and refrigerators so be sure they are plugged into unprotected outlets or you’ll end up with a lot of spoiled food."

Why do you say sump pump motors can wreak havoc with GFCI's? I followed the pump manufacturers instructions to install a GFCI and the NEC requirements for a GFCI in a wet location.

A. First we need to clear up a couple of items regarding GFCIs which stands for “ground-fault circuit interrupter” and the NEC which are the letters representing the National Electric Code.

GFCIs were introduced into the code in the late 1960s and were directed towards spas and swimming pools. What a GFCI does is sense an infinitesimally small leak of current toward ground when the current shouldn’t be going that way and trips, or opens, the circuit stopping the current flow. Most people first encounter them in bathrooms and they have little test and reset buttons of the face of the outlet and if you look closely is says “Test monthly”. No one ever does.

GFCIs are true life savers should a person be the ground source the current is trying to find. They will trip out between 4 and 6 milliamps-- that’s thousands of an amp. 20 milliamps across the heart muscle of an adult man will kill him-- 18 thousands across a woman’s heart muscle will kill her.

The National Electrical Code has been in existence since 1896 and its formal name is NFPA-70-- National Fire Protection Association section 70. Its original intent was to prevent fires. Fuses and circuit breakers protect circuits. GFCIs are designed to protect people. But those charged with of our safety noticed that people were routinely being electrocuted in very predictable situations and the introduction of GFCI type protection is intended to prevent or at least reduce that. The NEC is updated every 3 years and during the period of code review the code writers note where people are getting killed by electricity in or near the home and impose greater implementation of measures to prevent it hence the expansion of the required locations of GFCI use.

Later versions of the NEC require that sump pumps be placed on a GFCI protected circuit. I did some research and discovered that was the 2008 version that introduced that. However just because there is a code version like the most recent, the 2011 NEC, doesn’t necessarily mean that it’s being applied universally. They have to be approved by the local governing political body as to which will be followed. There are arguments pro and con and it can get heated. Around here we still basically follow the 2002 NEC with modifications.

We know that sudden starts of motors can fool a GFCI and cause it to trip, along with stray voltage from electrical storms and power surges and just plain old age will cause them not to perform as intended. Sometimes they wont trip and sometimes they will when they shouldn’t. That’s called “nuisance tripping”. That’s what happened to your sump pump. There was a universal understanding of that and the application of dedicated circuits for such motors was instituted as I noted in 2005. But it appears that code writers felt that a flooded basement or a freezer full of spoiled food was a small price to pay for the saving of a human life. And philosophically I agree.

Some electrical inspectors will allow the dedicated circuit concept and some-- depending upon which code they are under-- wont. But the electrician I recently spoke with on this subject told me he didn’t care. He was going to insure the sump pump is on an non-GFCI circuit because he didn’t want the phone call blaming him for the flooded basement. And I still stand by my 2005 position adding the caveat that a dedicated circuit is just that-- dedicated to the one device that’s attached to it and don’t plug the shop vac or electric drill into it just because it’s the handiest outlet at the time you need some power.

Keep the mail coming. If you've got a question, tip, or comment let me know. Write "On The Level," c/o The Capital, P.O. Box 3407, Annapolis, MD 21403 or e-mail me at jimrooney@jimrooneyonthelevel.com or inspektor@aol.com.