Block Heaters & GFI Outlets
 

I've been having problerms lately using GFI outlets with my block heater. The outlets sometimes trip when either plugged directly in, or thru a timer. It's been too cold here to risk starting headaches, so I replaced the GFIwith a standard outlet. I don't know whether it's a slight corrosion in the prongs or not, but I can't seem to resolve it. Was wondering if anyone else has had a similar problem? I don't think it's a hazardous situation as long as I don't go foolin' with the cord while it's wet. (Like I did last week)

Re:Block Heaters & GFI Outlets
 

GFCI's do go bad and are suppose to be tested periodically so you don't get surprised. Because you are keeping something plugged in full time, could snow, ice, etc. be getting into the prongs to cause internal corrosion? For what you pay, theyshould last forever! Is there a duplex on the circuit upstream where you could put a GFCI in and use a regular duplex. Then I would maybe put a warning that there is no ground fault. <br>Don

Re:Block Heaters & GFI Outlets
 

Commatoze, I take it you've isolated the problem only to the block heater. Does the GFCI trip only with the block heater, and works fine when you plug in &quot;anything else&quot;?<br><br>I think if you've cleaned off the plug/prongs, the only other place to look is where the wires enter the heater. I have often wondered how much stress is applied to the heater cord when I decide to take the timer and extension cord with me in the morning........ Mine is secured with tie wraps pretty good.<br><br>If the heater cord wasn't secured real good one time when you decided to take it with you, maybe it pulled loose a little, and over time, some dirt/grime/salt has leached in creating a current path. Would it be worthwhile to take a multi-meter to it?<br><br>I haven't graduated to a GFCI yet. I do have a timer on the ckt and control it from there before plugging and unplugging (most of the time anyways...).

Re:Block Heaters & GFI Outlets
 

If you have those GFCI's outside your buildings, I would hope that they are in WEATHERPROOF boxes rated for such use. For the weather that you're all facing, I'd certainly never bypass the use of a GFCI protected receptacle. There are several types of covers that can be added to help protect the receptacle. The absolute best solution would be to trace the circuit back to the electrical service panel and put a GFI breaker in that position. Yes, it's alot more expensive BUT, hey, that's a very good electrical conductor (you) plugging and unplugging the cord. It's like anything else, you get as good as you give. <br><br>~Dave

Re:Block Heaters & GFI Outlets
 

The outlet is in my garage out of the weather, and I run a 12/2 extension under the door seal. But, yes, I did try to take the cord with me a couple of weeks ago ::), so I might have damaged the ground wire around the plug. I've tried all 3 outlets, different extensions, so it has to be within the cord from the block heater. Other devices work fine. When it warms up, I'll remove the cord and replace it. Thanks.

Re:Block Heaters & GFI Outlets
 

A thought on the GFI's.<br>We've had all kinds of problems with test equipment when it was plugged into GFI outlets. A number of pieces that had 2 prong cords and some with 3 prong cords would trip the breaker. Wonder if the plug to the heater has just supply and return and no ground to the chassis? If so, that may be what's causing the problem. After replacing the GFI's in the shop with standard outlets, our equipment problems went away.<br>Like I say, just a thought.

Re:Block Heaters & GFI Outlets
 

[quote author=shortround link=board=8;threadid=10764;start=0#102869 date=1044891260]
A thought on the GFI's.
We've had all kinds of problems with test equipment when it was plugged into GFI outlets. A number of pieces that had 2 prong cords and some with 3 prong cords would trip the breaker. Wonder if the plug to the heater has just supply and return and no ground to the chassis? If so, that may be what's causing the problem. After replacing the GFI's in the shop with standard outlets, our equipment problems went away.
Like I say, just a thought.
[/quote]

Well if you look at this picture (courtesy of Cattle Hauler):


https://www.dieseltruckresource.com/...s/IM002091.JPG

It looks like the heater element has 2 pins; its own hot and neutral pins, and the shell is connected to the block via threads but I see no electrical connection to the ground wire in the cord, so there is nothing hooked to the ground prong back at the plug. Obviously they wouldn't tie the block heater's neutral and ground together at the shell. So, it looks like it's a 2 wire hookup with no ground. You know, I got zapped a couple of weeks ago with the GFI in place. This could be why.

Re:Block Heaters & GFI Outlets
 

Thats a great picture! The heating element is longer than I would have thought. Now I want to go look for it and see where its installed.<br><br>I'm not sure the number of prongs has anything to do with it. I only see two pins in the heater body. There has to be a third, or somehow the ground is connected to the body of the heater. The GFCI measures the balance of AC current &quot;goezins&quot; vs. the current &quot;goezouts&quot;. If everything is in balance (AC flow between the hot and nuetral), everything is happy. If there is a leak somewhere, upsetting that balance, GFCI trips almost instantaneously.<br><br>Too bad the weather isn't warmer where you could remove the plug wire for inspection. You might find a crack that is allowing some current to leak.<br><br>Commatoze, when you received the jolt, did the GFCI trip?<br><br>

Re:Block Heaters & GFI Outlets
 

[quote author=bulabula link=board=8;threadid=10764;start=0#102932 date=1044899845]<br>............Commatoze, when you received the jolt, did the GFCI trip?<br>[/quote]<br><br>No, it didn't trip. I foolishly grabbed a soaking wet (road salt) plug and the extension cord forgetting that I hadn't turned the timer off. I guess that qualifies for a Darwin Runner-up Award doesn't it?

Re:Block Heaters & GFI Outlets
 

LOL. Not even close! But there are more pleasant ways to get those old batteries recharged!

Re:Block Heaters & GFI Outlets
 

[quote author=NWDave link=board=8;threadid=10764;start=0#102825 date=1044883200]<br>If you have those GFCI's outside your buildings, I would hope that they are in WEATHERPROOF boxes rated for such use. For the weather that you're all facing, I'd certainly never bypass the use of a GFCI protected receptacle. There are several types of covers that can be added to help protect the receptacle. The absolute best solution would be to trace the circuit back to the electrical service panel and put a GFI breaker in that position. Yes, it's alot more expensive BUT, hey, that's a very good electrical conductor (you) plugging and unplugging the cord. It's like anything else, you get as good as you give. <br><br>~Dave<br>[/quote]<br>Most of the ones I have replaced were in the bathroom, probably went bad from hot, steamy showers. The outdoor ones don't have weather protection when something is plugged in. I have had new ones that wouldn't test good. I have also had problems come to think of it, with certain tools tripping them. I wasn't really suggesting not having an unprotected circuit. Just thought if you replace one with a regular duplex, would the GFCI upstream protect the circuit, but still allow the use without tripping, as it is not directly plugged in? Not barking here, just thinking out loud.<br>Don

Re:Block Heaters & GFI Outlets
 

I plug mine in exactly like Commatoze, receptacle is in the garage, extension cord goes out under the door to the truck.
Have it on a timer, so it's usually not hot when I plug in.

Don't know if it is up to &quot;code&quot;, but the entire garage is routed through one GFI outlet.
This outlet is in the back of the garage, and the one I plug into is right by the door.

I've only had the GFI trip once, that was when the siding guys were putting the siding on, siding (aluminum) slipped and shorted their saw plug. (which wasn't pushed all the way in, in the plug outside the garage)

So, if the block heater is missing it's ground (3rd prong is just for looks) that hasn't caused mine to trip.

Cattlehauler's is a 99, maybe they fixed that for the 2002's?
I know the cord is different, his appears to be flat, mine is round.

I haven't tried to drive off still plugged in yet either.

When I'm not using the extension cord, I just coil it up and hang it on the handle of the side &quot;man door&quot;, out in the elements and all, that way I don't have to open and close the garage door just to plug in.

phox

Re:Block Heaters & GFI Outlets
 

GFI's are a good thing to have.<br><br>As part of training at work, we had to watch some films in which there was a home video of a teenager who had washed his car in the driveway. He was barefoot and when he flipped the switch on a shop vac to do the inside of the car, got zapped and could not be revived. Another was a young girl drying her hair and touched the sink. Luckily, she survived but it knocked her cold. GFI's could have prevented either of these from happening.<br><br>Most of us have been 'bitten' by 115 AC at one time or another and consequently have lost our respect for it. It takes only 100 mA to cause you to stop breathing, and there's usually 15 Amps or more available at any outlet. I don't remember what a GFI will let through, but it's far less than 100 mA. Most of us that have been bitten have been very lucky.

Re:Block Heaters & GFI Outlets
 

[quote author=bulabula link=board=8;threadid=10764;start=0#102932 date=1044899845]<br>Thats a great picture! The heating element is longer than I would have thought. Now I want to go look for it and see where its installed.<br><br>[/quote]<br><br>Here is where the heating element is located, on the passenger side of the engine block, right to the back of the engine oil filter.

Re:Block Heaters & GFI Outlets
 

Several stages of being bitten by 110:

:o ZAPPPP

[eyecrazy] immediate brain shuffle

::) boy, that was stupid

8) looks around to make sure no one was watching

;D no one saw me

This is nothing to be playing with seriously. Like we were told in class, less than 1/10th of and amp can kill you and there is usually a minimum of 15 or 20 amps available at your friendly local 110 v outlet. Take time and do it right.