Jenn-Air cooktop wiring help

Discussion in 'General Electronics Chat' started by tracecom, Sep 16, 2013.

  1. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    We got new counter tops in the kitchen today. I disconnected the counter top range, and I noted that the bare wire in the Romex went to the green on the range, the black wire in the Romex went to the black on the range, and the white wire in the Romex went to the red on the range. (At least, that's what I think I remember, but it has been a long day.)

    When I went to hook it back up, there was a small white wire from the range that I hadn't noticed when I unhooked the wires, but it was obvious it needed to go somewhere. Fortunately, I found the attached wiring diagram for the range, and decided that the small white wire was for the fan and the indicator lights. I hooked it to the white in the Romex and hooked the other wires as indicated above. Turned on the breaker and turned on the fan; it worked, so I thought I was home free.

    While I was getting ready to install the plug in cooking elements, the fan quit. I turned off the breaker, rechecked the bug nuts, found nothing wrong, and turned the breaker back on, and then turned the fan on. It worked again. So, I am baffled why the fan quit and then started again.

    What could be wrong? Thanks.
     
  2. shortbus

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    Sep 30, 2009
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    Doesn't one of the burners need to be on for the fan to work? It may have a fan test default that only lasts for a short time then shuts the fan off. I'm assuming its the Jenn-aire type with the surface mounted fan across the back of the cook top.
     
  3. tracecom

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    It's a down-draft fan, which comes on automatically when the grill is on, but can be turned on any other time as well.

    Since my last post, I turned the fan back on. It ran a while and quit, then after a few minutes, I turned it on again and it started again. I am now thinking that it has a resettable thermal fuse that opens when it gets too hot, and resets when it cools off.

    If that's the case, I wonder why it's overheating. I did have the filter in wrong, and maybe that was restricting the air flow, which overworked the fan motor and caused it to get hot.

    Anyway, I am thinking it's not a wiring problem, but my self confidence is shot for the day.

    Thanks for the suggestion.

    ETA: The heating elements and indicator lights all work as expected.
     
  4. tracecom

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    Okay, I put the filter in correctly, and turned the fan on. It only ran about a minute and shut itself off. The fan is turning freely, but the motor is hot to the touch. Now, I am thinking I have something wired wrong.

    Maybe someone can look at the diagram in post 1 and tell me what I did wrong? Thanks.
     
  5. JohnInTX

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    Jun 26, 2012
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    Based on pp2 of the wiring diagram, it looks like its a 240V unit (black and red are std. colors for 220V) with the white being a neutral. L1 to neutral provides 120V for the fan/indicators etc. Your power will have to be 240V with a neutral plus green ground, I think. It sounds like the 120V fan motor may be running at 240V until its overheat switch cuts it out (speculation)?

    Based on your romex description it looks like 240V with ground but no neutral (the white wire in the romex should have been taped with another 'power color') so you may have some wiring to do to bring 4-wire 240 with a neutral to the unit.

    I am assuming that the unit you replaced is also 240V, yes?

    And you know that ground is ground and can't be neutral..
     
    Last edited: Sep 16, 2013
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  6. tracecom

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    Thanks for your help. The unit that went in is the same unit that I took out. Yes, it is on a 240V breaker, and worked fine before, fan and all.

    I just took it out so that the counter top could be installed. There were only three wires in the Romex: bare which I connected to green on the range, white which I connected to red on the range, and black which I connected to black on the range. Then, I noticed this small white wire from the range, which I connected to white in the Romex. I think that is for the indicator lights and the fan, but I am not sure where it was hooked up before I took the cook top out.
     
  7. #12

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    Nov 30, 2010
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    I think John nailed it. The old fan might have been a 230 volt fan and that's why it worked properly...or did it burn out and you just never fixed it before you threw the old one out?
     
  8. tracecom

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    See, that's the thing. I put back in the exact same unit I took out - not a new or a different one - but the same exact unit. And the old unit worked, fan and all. All I can figure is that whoever wired it used the bare wire as neutral, and that is where the fan got its 120V.

    I flipped the breaker off, and it looks like I have to get new 4-conductor wire run from the breaker to the range.

    Thanks.
     
  9. JoeFromOzarks

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    Apr 14, 2010
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    I bet you're correct. Check out the drawing. ("Green" wire in the drawing would be your bare copper.)

    :) joe

     
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  10. #12

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    That's the "proper" way to do it.
     
    Last edited: Sep 17, 2013
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  11. wayneh

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    Sep 9, 2010
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    My Jenn-Air, installed in 1992 prior to the rule change in 1996, is supplied by a run of 8/2 G Essex NM B cable. I believe it would be judged "illegal" per the diagram above.
     
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  12. JohnInTX

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    Jun 26, 2012
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    Interesting. I need to go back into my old code books to see when/if it changed. But I once was slapped down by a journeyman electrician (in the 70's) for doing just that sort of thing. My protestations about a small current on ground being OK were met with a really uncomfortable stare... 'You should know better' was all he said.

    That's all it took, too. 'Nuff said.
     
  13. #12

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    I still have a Kenmore clothes dryer with a 3 wire, 240V cord, and 120V light bulbs.
    I don't know how they got away with that. Probably an exception was made for extremely large corporations.
     
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  14. killivolt

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    Jan 10, 2010
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    Post removed, why did you post that section of the schematic?

    In the first post I see you removed and replaced, the cooktop?

    Now I see the section of the schematic that suggests to me your repairing a section of a cooktop?

    I'm confused?
     
    Last edited: Sep 19, 2013
  15. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    I removed the cook top so that new counter tops could be installed. After the counter tops were installed, I put the same cook top back in. That's when I discovered the wiring problem, which is now resolved.

    Thanks to all for your help.
     
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