Hard Wiring a Sealed Heating Element

[rp2813]

I recently picked up the GE rotisserie shown in the picture below.  The motor was stuck and I had to take the unit completely apart to get at it.  Once I had the motor freed up and working, in the process of re-assembling, thanks to GE's assumption that nobody would ever need to get at the motor and decision to make the wires as short as possible, all of the fiddling around caused the connection to break at the end of the heating element.

 

It appears the three leads that were attached to the element were held there by a stiff wire that was, I presume, tack welded onto the end of the element.  Part of that wire is still on the element and part of it is still attached to the ends of the leads.

 

This is your basic tubular heating element with a short metal post protruding from each end. 

 

What is the best way to try and re-attach the leads to the element?  I doubt solder would work, although probably an inch worth of the actual element sticks into the motor chamber at each end, which makes me think it might not get that hot at the connecting point.

 

I don't think I can fix this like I did the nichrome heating element on my GE roaster oven.  I don't own a welder.  I'm currently considering some type of sleeve that can fit over the end of the element and also contain the wire from the leads, fastened together and onto the element by a screw, but am not sure if I can find such a thing.

 

Any suggestions are welcome.

 

I'll post a picture of the connection point if it will help.

 

[norgeway]

Their has to be

A way, maybe take it to an electric repair shop and they can weld it, they can do wonders with a wire welder these days, that is a fantastic item!

 

[rp2813]

Well Hans, in a city of over 1,000,000 we have only a single small appliance repair shop left.  I've called them about other items in the past and they simply say they don't repair that make or something that old.

 

Since this type of repair would apply to a lot of heating devices, even newer ones, that are quite likely wired similarly, I might have a chance of getting them to fix it.  If I can't find a way to do it myself, I'll give them a call.

 

[rp2813]

Here's a picture of what I'm dealing with, including the group of three detached leads.  You can also make out the other end of the element in the background with a single wire attached.  The rest of the element can be seen on the right, inside the roasting cavity (the unit is upside down in order to access the gear case).

 

[rp2813]

Solder Might Work . . .

The link below indicates that the connection end of the element won't get very hot at all.  That being the case, it seems like soldering will do the trick.

 

Scroll down to the copy below the X-ray shot.

http://elementsofheating.wordpress.com/2012/10/04/what-is-a-heating-element/

 

[kb0nes]

Ralph,

I think you should be able to do just fine with a high temperature crimp butt splice. These are made of nickel plated steel and good to 900 deg F or so. Its a bonus that the wire is stranded so its more complaint in the crimp. I'd insert the wire and the element end all together in the barrel to give more material crush in the crimp. Just remove any remaining weld material on the end of the element and crimp the deal together, I bet it will give years of service. I repaired a conveyor pizza oven at a place I used to work and its still running today.

You may be able to find high temp terminals at a decent local hardware, otherwise Google will find them for you. McMaster Carr 7971K42 would likely work depending on your wire sizes but you have to buy 100 pieces for ~$8.00...

 

[kb0nes]

I don't think solder would work. The high nickle surfaces are difficult to get the solder to wet to without resorting to aggressive acid fluxes.

Its pretty clear from the discoloration of the exposed element that it gets hot enough to have a standard tin/lead solder joint fail quickly.

 

[rp2813]

Thanks Phil.

 

I bought some crimp splicers for the GE roaster I repaired, but they weren't rated for the high temperatures of the nichrome element.   That's why I went with the brass & borax fix instead.  I think they might be the right size for this operation though, but IIRC they're only rated up to 650 F. 

 

Also, the red & white wire pictured is not stranded.  In fact, now that I'm thinking about it, the piece of wire left on the end of the element likely belongs to the red & white lead.  You can see the connection at the other end of the element has only a red & white wire, and it's solid just like the broken piece.

 

The black and the green & white leads are stranded, but all three are crimped together.  If I removed the crimp and stripped the wires, I'd likely not have enough of the red & white one to reach.  As I said above, GE wasn't at all generous with the amount of wiring provided.

 

I wonder if there's a way to un-crimp those three.

 

[rickr]

Hey there, Ralph!

I used to work part time after high school at a small appliance repair shop in the early 1970's. We used to silver solder leads to the elements. Silver solder melts at a much higher temp. Heating and air conditioning repair shops still use silver solder to repair copper a/c lines. If all else fails, perhaps you could find an a/c repair person willing to silver solder that for you.

 

[norgeway]

RE Silver solder

That would work , i think, you have to have aceyteline or mapp gas to do it, lp just isnt hot enough, its not difficult, my uncle, a retired electrical contractor, repaired countless dryer and open coil units in ranges with the butt splice thing..

 

[kb0nes]

If all the wiring was bare, silver solder would work. Depending on the alloy silver solder alloys will melt between 1000 & 1500. Deg F, no chance the wire insulation can survive that, it looks to just be cloth. First do no harm...

It is a pity they didn't leave a little extra wire in there. You may have to just replace some wire or just add a short jumper from the element to where the wires combine. In any case a crimp sleeve is your best bet for success.

 

[rp2813]

Thanks to Phil, Rick and Hans for sharing advice and experiences. 

 

The crimp sleeve is for sure the more DIY of the two suggestions.  Considering that the wires haven't discolored at all, could it be possible that temps at the connection might not exceed 650 F?  If not, I'll have to find butt splicers with a higher temperature rating.  I don't need 100 of them, but McMaster Carr could turn out to be the best option.

 

I think the jumper between the element and the three wires is a good idea.  I already extended a couple of wires that connect to the AC cord in order to provide myself with more room to work.

 

Silver soldering by a pro would be the next pursuit if for some reason the butt splice method goes awry.

 

[stevet]

Try these on for size and space!

Ralph,

There was a thread on a KA sheath heater that had a broken terminal and I suggested
using a "bug" nut type of connector similar to the ones in the link below. They are available at HD or Lowes and they also carry the type without the hole on the one end. Once tightened down they should work for years.

Hope this helps
Steve

http://www.elecdirect.com/catalog/solderless-lugs

 

[stevet]

Split bolts, maybe?

These are the other ones I mentioned. May work better.

http://www.elecdirect.com/catalog/split-bolts-grounding-products

 

[rp2813]

Thanks Steve!  That's more or less what I had in mind originally.  I'll see what I can find at OSH, Lowe's or HD.  This method would be the easiest, as crimping could prove to be a hit or miss operation considering the awkward clearances I'm having to deal with.

 

[rp2813]

Progress

I got some heat resistant wiring and attached a jumper to give me room to work at the stub on the end of the element.  I used something similar to the solderless lug pictured in the link from Steve and it seems to be holding well.

 

I hooked up the power and everything works, however a new issue has cropped up.  I used wire nuts to make the connections to the power cord and I noticed that after just a couple of minutes of operation, the A/C cord sections near the wire nuts were quite warm.

 

Originally, GE used crimped connections to the power cord, but I had to snip those in order to make my repairs.  I don't know how much difference it could make by using wire nuts, but I'm not ready to reassemble the unit until I've resolved this problem.

 

Any suggestions?

 

[kb0nes]

Please define "quite warm", as in you can't touch it at all or?? My hunch is you are likely concerned for nothing, a phenolic wirenut will be fine up to a few hundred degrees i.e. too hot to touch in any case. Put it together and use it, worse case is that it stops working someday.

 

[rp2813]

Thanks for the advice.  It wasn't too hot to touch.  I didn't leave it running for long because I wanted the element to be cool before re-assembly.  I might add that at the same time, the end of the element where I made my repair remained cool to the touch.  I'll go ahead and give it time to get red hot and see if there's any change in cord temperature.  Typically, it can take 75 minutes or more to roast a chicken, so I don't want what is now nice, pliable rubber sheathing on the A/C cord to turn crispy where I can't get at it.

 

Disassembling this thing to access the guts is way more involved than on my Roto-Broil.  There isn't a single screw that didn't have to be removed.  That's why I want to be sure I can close it up and not have to take the whole thing entirely apart again in the near future.