So your problem has disappeared, but you are worried it might recur? I wouldn't touch it unless it happens again.

If so, the only things I can think of are:

1. install a new GFCI; they go bad outside with some regularity;

2. put in a GFCI upstream in the circuit, and switch out the exterior GFCI for a regular receptacle; this is legal, will protect the GFCI from the weather, and will provide GFCI protection to the regular receptacle.

ronnaltalie,

Yes, we have done a lot of visual inspections. We have a cover for the outside outlet, but since the heat tape is always plugged in, it is always open. The outlet is located immediately below the eave of the garage roof, so it is protected fairly well against the elements.

kudzu,

Yes, I am thinking the problem will recur when Ice dams build again, and I need it. Finding the problem is not possible then, as you cannot get at the heat tape, as it is under Ice and Snow.

1.) The GFCI is already located in the Garage, and a regular receptacle is the one on the outside.

Can a bad GFCI behave intermittently? Like tripping in the Winter and working OK the rest of the year?

This post was edited by cut-throat on Thu, Aug 15, 13 at 14:26

After reading your response, I'm more inclined to think that ronnatalie is correct about the fault being in the wiring. Unfortunately, based on your experience, this may mean that there is a small flaw, hard-to-detect flaw in the jacketing that only exposes the wires to faulting when the cable is subjected to freezing.

Yes, we have done a lot of visual inspections. We have a cover for the outside outlet, but since the heat tape is always plugged in, it is always open.

This is NOT an in-use cover then. An in-use cover remains in place, shielding the receptacle from the weather WITH THE CORD PLUGGED IN. It is now required by code on exterior receptacles.

For equipment protection and de-icing equipment, etc., you only need class B protection not Class A.

You could always wire your heat tape using one of these GFI devices.

They are a little pricey however, may reduce nuisance trips.

Here is a link that might be useful: 30 ma GFI

Of course, there's no guarantee that the 30ma GFCI will help. Absent knowing what is going on, it might not be a "nuisance" trip but a legitimate fault. However, since he has a open receptacle I'd invest in an in-use cover for under $10 or so before attempting anything else.

Why not eliminate the receptacle altogether and hard wire the heat tape in the box where the receptacle is and put a blank on it since the GFI is in the garage.

Thanks for all the suggestions!

I installed an In-use Electrical Cover today and replaced the GFCI with a New One. There is quite a large opening in the bottom of the box for the cord . I am thinking of plugging this,otherwise it looks too attractive as a home for small animals.

I won't know if this fixes the problem until next winter, but if it doesn't, I have a pre-1971 solution for this. After all, I am a child of the 60s. No seat belts, No Air bags, First and Second hand smoke. And somehow I'm still alive.

This post was edited by cut-throat on Fri, Aug 16, 13 at 14:52

Good luck. Please post back after you make it through the winter.