Save the meat.

December 29, 2008 9:05 PM

Chest freezer and GFCI outlets. What's the solution?

I just bought a chest type freezer and noticed the mfg recommends not plugging it into a GFCI outlet. My garage, of course, only has a GFCI outlet - although it doesn't appear to share a circuit with any other outlets.

Its my understanding that here in Arizona the electrical code prohibits anything but GFCI outlets in the garage. Houses here (mine included) are mostly built on slabs with no basement. Having no other practical place to put a freezer but in the garage, there must be a solution. I'd like to avoid having the freezer trip the GFCI and thus defrost the contents.

Two questions then...

A) What is the likelihood the freezer will trip the outlet with nothing else on the circuit?

B) Are there other code compliant solutions that would enable the freezer to stay in the garage but without the GFCI protected outlet.

posted by whatisish to home & garden (15 comments total)

I think the reason they don't recommend having the freezer on a GFCI is the same reason you don't want your computer on a GFCI -- not because the freezer itself is likely to trip the GFCI, but because if the GFCI trips, the negative consequences could be significant. If it is in the garage you can simply check regularly to make sure it's running. (Or plug an LED night-light into the same outlet so you can visually check to make sure it's working.)

As a practical matter, it's your house and nobody is going to pull a surprise inspection to make sure you're up to code. I'd just replace the GFCI with a regular grounded outlet and forget about it. Put the GFCI back in before you sell the house, if you think anyone will notice. Doing this won't make the house any more likely to burn down or anything like that (that's not what a GFCI is for).
posted by kindall at 9:36 PM on December 29, 2008

If the freezer is working properly, the GFCI shouldn't trip, but as an extra precaution I would use something like this in the same outlet.

Alternatively (or if the alarm sounds regularly), you could violate code and install a non-GFCI outlet. Ideally it should be used for this single appliance, and be in a location not easily accessible (like behind the freezer). This was allowed by code until recently, and would pose no real danger.
posted by Knappster at 9:38 PM on December 29, 2008

So when I had my garage rewired I had a non gfci outlet installed for a freezer., however, you can swap out the installed GFCI outlet to one that has a built in LED to determine at a glance if it's functioning.
posted by iamabot at 9:46 PM on December 29, 2008

I'm obviously no electrician. Is the outlet the only thing that makes it GFCI? Is replacing the outlet with a standard non-GFCI outlet all it takes to make it work and still be wired properly/safe? If it matters, it's on it's own 10kA 120/240V circuit breaker.

Knappster, thanks for that alarm. I'd seen that previously but didn't read it carefuly enough to notice it has an audible alarm.
posted by whatisish at 9:59 PM on December 29, 2008

I'm 99.9% sure* you can just swap out the outlet for a standard grounded one and your freezer contents and your garage will be perfectly safe. Ground-Fault outlets are usually used where water is likely to be present, which I'm guessing won't be your garage.

*I am not a certified electrician. Use common sense.
posted by maniactown at 10:16 PM on December 29, 2008

Is the outlet the only thing that makes it GFCI?

That's it. Installing a GFCI is no different than installing a non-GFCI outlet, with one exception: there are different sets of screws on the GFCI outlet for the wires coming in from the power source and the wires going out to downstream outlets. A single GFCI outlet will protect any other outlets that are connected to it "downstream."

So long as the non-GFCI outlet you install is properly grounded and not easily accessible by someone standing in a puddle of water, it should be perfectly safe.

If it matters, it's on it's own 10kA 120/240V circuit breaker.

There should be one additional number on the breaker (maybe on the handle), and it's probably 20A. That would be standard for an appliance circuit like this.
posted by Knappster at 10:18 PM on December 29, 2008

Is the outlet the only thing that makes it GFCI?

No -- sometimes GFCI plugs are wired in a series, where an "upstream" GFCI outlet protects a series of downstream outlets. So depending on how your garage is wired, the freezer outlet may be a stand-alone GFCI outlet, a GFCI outlet responsible for downstream outlets, or even a GFCI outlet that is downstream from another GFCI outlet. You can't know by looking at it, especially if (re)wiring was done ad-hoc by a homeowner rather than to code.

The alarm is the cheapest solution; otherwise either bring in an electrician or get some books and put in the time to figure out just what is really going on with the wiring. Don't simply swap outlets and consider it done.
posted by Forktine at 10:29 PM on December 29, 2008

my electrical code-fu is a couple of editions out of date, but i *think* that the gfi requirement is only for "general purpose" outlets. if you have a specific outlet (which may or may not require a separate circuit), you can use a non-gfi outlet.

if so, be advised that the particularly pedantic inspector may require a single outlet rather than the more common duplex receptacle.
posted by rmd1023 at 5:02 AM on December 30, 2008

whatisish writes "Is the outlet the only thing that makes it GFCI? Is replacing the outlet with a standard non-GFCI outlet all it takes to make it work and still be wired properly/safe? If it matters, it's on it's own 10kA 120/240V circuit breaker. "

Is the actual outlet GFCI with the test button? Then yes. It's also possible for the breaker supplying the outlet to be gfci. If there are only one set of wires connected to the outlet (probable) then you don't have to worry about down stream devices.

I wouldn't swap out the outlet, the code has been updated for a reason and you'd hate yourself forever if your freezer killed your dog/kid/mother sometime in the future. Much better is an alarm on the circuit. My CO detector screams bloody murder when it gets unplugged, louder than our smoke detector. Just plug something like that into the same outlet and be done with it.
posted by Mitheral at 6:01 AM on December 30, 2008

Thanks all. Fwiw, I've plugged in the freezer and let it run for long enough that it has reached its default temperature without tripping the GFCI. I'll likely just leave things as they lie and look for an alarm that is particularly loud. The customer reviews of the one previously mentioned are critial of the alarm not being loud enough. If I have any later problems, I'll consider it a lesson learned and do what it takes to replace the outlet with a non-GFCI version dedicated to the freezer.
posted by whatisish at 7:27 AM on December 30, 2008

I believe that the freezer shouldn't be on a GFCI circuit mainly because if the breaker did trip for some reason (even a momentary flicker outage), the freezer won't come back on until you go and manually reset the outlet (which may be hidden behind the unit itself).

You could easily lose a freezer full of food if you weren't careful. Anyone else know of a safety reason for this requirement?
posted by Aquaman at 8:14 AM on December 30, 2008

Wireless freezer thermometer, but its probably better to just install a regular outlet.
posted by damn dirty ape at 8:52 AM on December 30, 2008

Seconding the "power failure alarm" -- I use these on aquariums where I need the GFCI but where things will go terribly wrong if it gets tripped. You might even consider putting one of these on an extension cord so it can be placed where you can more easily hear/see the alarm.

If you're of a more geeky persuasion, in the same applications I also have a network device that's "pingable" attached to ethernet and powered on the same circuit (this could be something like a simple NAS box, an old router, whatever), and I use a network monitoring program on my desktop machine to send an email to my cellphone provider's SMS gateway to text me if the device stops responding...
posted by nonliteral at 10:57 AM on December 30, 2008

IAAE: I do believe the freezer could trip the GFI. The freezer has a motor/compressor. When motors start they can draw a huge amount of amps for a millisecond spike. This normally does not trip a regular breaker as they have presets for this and a millisecond isn't long enough. The large draw in amps reduces the voltage for a milisecond and you have witnessed this phenomena when the lights dim when your refrigerator compressor motor kicks on.

Since GFIs are sensitive up to 5 MILI-amps of leakage to ground they still might trip on a motor start spike even though there is no leak to ground due to the sensitivity of the internal mechanisms. The spike draw gets "longer" as the motor gets dirtier over time, so that might be why the freezer mfg says not to use a GFI.

If you turn the breaker feeding the GFI off and the GFI is the ONLY thing off then you can just add a second outlet on the same wire in the GFI outlet box, that is not a GFI, and use the GFI (if ever) for the regular garage stuff, someday you might have water or oil on your garage floor and an extension cord or the garage door open in the rain while you work some project inside. Codes are generally not made for imagined reasons but after finding out real world problems and seeking to mitigate them so dont make a regular outlet in the garage only.
posted by Kensational at 12:05 PM on December 30, 2008

My freezer plugged into a GFCI went for months without tripping and defrosting everything. Since that outlet was freezer only I switched it out.
posted by pointilist at 9:30 PM on December 30, 2008