Block Heaters Won't Work Without Electricity! Doh! - PeachParts Mercedes-Benz Forum

deluvak · #1 01-23-2003, 06:33 PM

The thermometer on my garage read 11 degrees this morning, so I thought this would be as good an opportunity as any to use my block heater for the first time. I ran a cable from my porch outlet to the car and went back inside to enjoy my breakfast. I was certainly disappointed to find later that as soon as I had plugged the block heater in, it must have blown the outdoor outlet's GFCI. I reset the GFCI several times, but it still kept blowing. So I plugged it into an indoor outlet which worked just fine.

Is this a common thing with GFCIs?

Dan
85 300D

billrok · #2 01-23-2003, 10:28 PM

You should try another appliance in the same GFI receptacle. Try a small bathroom heater or a blowdryer. If it continues to blow you have a bad GFI. Very common in the ones used outdoors. My outdoor GFI is a dedicated 20Amp circuit and I have no problem with my block heater or anything else. I plug my car in every night. Wow-do we need it lately here in the Chicago area!

#3 01-24-2003, 07:15 AM

I expect that you have a low wattage or bad ground fault isolator. The block heater requires a little under a kilowatt. Your ground fault isolator may be rated lower than this.

Good luck,

deluvak · #4 01-24-2003, 11:16 AM

Thanks, guys. I'll check out the GFI.

Dan

tryan · #5 01-24-2003, 01:04 PM

gfci's blow when the current on the hot wire is not the same as the current flowing through the neutral. (nec code now requires arc arrestors on bedroom circuits.)

one drop of moisture will make them trip. make sure everything is kept dry.

i have bought new ones that are bad. if they trip hard a few times , i would replace it.

seymor and pass are good. eagle brand suck. if you do replace it , make sure line and load are hooked up correctly. if you hook it up backwards you will have no protection.