Advertisements

Kenmore 362.75581890 Stove: Weak Oven Igniter

The burner in our oven failed in December 2006, probably because the charred remains of an insect produced a hotspot:

Burned Oven Tube Overview

Burned Oven Tube Overview

That replacement burner came with its own igniter that failed after 8.5 years, with symptoms of slow oven ignition and the occasional smell of propane.

In normal operation, the igniter element glows yellow-hot for a minute or so before the valve opens, gas flows over the igniter, there’s a muffled whoomf, and the oven begins heating. The igniter remains powered as long as the oven is on, emitting a baleful yellow glare through the slots in the oven’s lower cover.

It consists of a ceramic base holding a stout resistance heater that apparently suffers from increasing resistance as it ages, reducing the current to the point where it won’t activate the gas valve.

I didn’t know that, either, but Google sees all, knows all, and tells most.

The gas valve label says it requires 3.3 to 3.6 A from the heater to turn on the gas:

Kenmore range oven gas valve - data plate

Kenmore range oven gas valve – data plate

But the old heater was good for barely 2.6 A (there’s a bit of parallax in this view):

Kenmore range oven gas valve - weak igniter current

Kenmore range oven gas valve – weak igniter current

Igniters range from $18 to upwards of $60 on Amazon, so I picked the cheapest one, waited two days, installed it, and measured 3.5 A at First Light, down to a bit over 3.0 A at running temperature. That’s on the low side of the valve’s spec, but it seems happier with an extra half amp.

We’ll see how long this igniter lasts; maybe next time I’ll double my spend…

Advertisements

  1. #1 by madbodger on 2015-08-29 - 09:16

    As Sears is a department store, not a manufacturer, they don’t make anything themselves. Happily, the actual manufacturer is encoded in the part numbers. Your oven is manufacturer code 362, which is GE. A genuine WB13K21 ignitor is $37 from repairclinic.com, where I buy many of my replacement parts. I, like you, avoid buying too-expensive parts: the starter assembly for my fridge compressor was such, and (after verifying that was what was needed with some motor start capacitors and clip leads) I got a cheap one from eBay. Like you, I’ll see how long it lasts.

    • #2 by Ed on 2015-08-29 - 09:49

      manufacturer code 362, which is GE

      I find it exceedingly hard to imagine that “General Electric” actually manufactures those igniters, except in the sense that the label on the bag has “GE” printed on it.

      With that in mind, though, getting a bag (from a reputable source!) sporting a GE label increases the probability of the igniter falling within, mmmm, ±2 σ of its performance spec. [grin]

      The one I installed evidently came from just below that cutoff…

  2. #3 by Christoph Loew on 2015-08-31 - 06:22

    Wow – so your gas oven draws around 300 Watt if I understand this:
    http://www.appliance411.com/faq/gas_range_ignition_systems.shtml#glow
    http://www.appliancerepair.net/oven-repair-6.html
    correctly?

    Isn’t electrical power too expensive for this to make commercial sense?

    • #4 by Ed on 2015-08-31 - 09:28

      make commercial sense?

      Ah, but the power cost is an externality for the manufacturer: that electricity costs them nothing!

      The real motivation probably has something to do with being absolute, positively certain that the flame will never, ever blow out under any possible conditions. Keeping the igniter glowing means never having to pay for scattering a kitchen into the neighboring yards.

      • #5 by Christoph Loew on 2015-08-31 - 10:02

        I was thinking from the customer’s side – no sense buying a device that wastes electricity while burning gas.
        Over here they’ve added efficiency ratings even to gas ovens:
        http://www.newenergylabel.com/uk/labelcontent/ovens/ovens_gas
        so a device like yours would be a harder sell.

        Probably one of the reasons why I’ve never seen this design in Germany or Japan.

        OTOH over here repair work like that is only done by accredited professionals and fixing an oven yourself would risk your fire insurance…

        • #6 by Ed on 2015-08-31 - 12:31

          no sense buying a device that wastes electricity while burning gas.

          Basically, who knew? I certainly never thought it would work that way!

          The four burners on the top surface have electronic sparkers. Set the knob to LITE and little lightning bolts ignite the gas, then you turn the knob to the proper setting and the lightning goes away. That makes sense!

          Our next stove will be all-electric, because low-usage propane costs so much that it’s simply not worthwhile.

          • #7 by Red County Pete on 2015-09-01 - 22:39

            low-usage propane costs so much

            Hmm, I suggest you call around a little. When we changed vendors prior to getting a propane range, we found the regional outfit cost $1.00 a gallon less than the Big National Propane outfit. I’ll skip the chicken-guano aspects, but the regional outfit is much more responsive.

            Dunno if it’s legal where you are, but I’ve seen installations that use one or two 50 or 100 pound tanks that can be filled locally. I do this (legally) for Julie’s stand-alone shop. Wrong side of the house to tie it into the big tank… I use two 50# tanks with an automagic cutover valve. Works well.

            • #8 by Ed on 2015-09-02 - 07:42

              call around a little

              We did! [mutter]

              A gas stove doesn’t burn enough propane to get over the minimum annual usage limit, which adds another buck a gallon. Plus the delivery charge they said they’d never have when we signed up. Plus paying top dollar, because their price keeps pace with, uh, the reciprocal of the propane spot price.

              Aaaaand the tank removal charge, should we switch to another supplier.

              Next time, we’ll know better…

            • #9 by Red County Pete on 2015-09-03 - 09:24

              Interesting. Our vendor doesn’t care, since we’re delivery-on-demand, with 2-4 week lead times unless we get in a bind. I’m not sure if the BNP wanted to charge tank removal, but I offered to charge them rent if they kept it here too long. It was gone a week after I sent that letter. On the other hand, they still tried to charge me rental 3 months after the tank removal, but that was due to the usual lack of communications between the local office and the national one.

              A side effect of a major pipeline project is that some of the local towns are getting natural gas hookups. I doubt we’ll see it–we’re too tiny.

  3. #10 by Mike on 2015-09-01 - 03:08

    “The igniter remains powered as long as the oven is on”

    I have a similar unit, with the same design. Came with the immobile home.

    There’s gotta be a better way to do that job.

    Maybe an IR sensor that closes a gas valve and sets off a buzzer if the burner goes out.
    I remember seeing a 2-coil gas valve years ago in the surplus store… pulse one coil
    to turn it on, pulse the other coil to turn it off.

    Or something that would drop the wattage once ignition took place.

    • #11 by Ed on 2015-09-01 - 08:58

      All those options increase the cost-per-unit, so they’re, ah, non-starters…

      I absolutely refuse to gimmick a toggle switch in the igniter line! [grin]

  4. #12 by Mike on 2015-09-02 - 14:15

    “All those options increase the cost-per-unit, so they’re, ah, non-starters…”

    On production units, yes, but not for geeks….

    “I absolutely refuse to gimmick a toggle switch in the igniter line! [grin]”

    Yeah, I’d want to make any addition transparent to the user, but still, there’s gotta be a better way…

    • #13 by Jim R on 2015-09-02 - 17:34

      “I absolutely refuse to gimmick a toggle switch in the igniter line! [grin]”

      But the gas valve runs on 3.3 volts, so you would have to build a supply for the valve that is triggered by the ignitor and then held on by the flame sensor you would want to install…

      “Our next stove will be all-electric, because low-usage propane costs so much that it’s simply not worthwhile.”

      Look on the bright side – you’re getting a bonus of about 1000 BTU of relatively cheap electric heat…

      • #14 by Ed on 2015-09-02 - 21:17

        about 1000 BTU of relatively cheap electric heat…

        Which gets lost in the roundoff from the oven burner. In the summer, we schedule our baking for late in the evening with the windows open and the fans running.

        Our next house will have central air conditioning…

        • #15 by Red County Pete on 2015-09-03 - 09:13

          A few of the Weekly Pizzas were done in the gas grill this summer, with cheap 12 x 12 floor tiles cut to make a “stone”. Hard to control the temperature (thermal mass on 12 x 21″ worth of tile is a lot for the grill), but when we had 90+ temps, it helped. Forecast high is in the 60s today, so it’s finally time to do a couple months worth of GF rice-based bread. (Yeah, the pizza is also gluten-free. Julie is allergic to gluten, and I’ve been intolerant of it long before it was cool.)

          • #16 by Ed on 2015-09-03 - 09:24

            A long time ago we picked up a Genuine Round Pizza Stone at a tag sale. It came with a few oil spots, so I heated it all by itself on the grill, whereupon it released The Great Stink while smogging the back yard; mosquitoes fell from the sky. After a couple of burnouts the smoke died down, but, sheesh, did they just pour oil into the poor thing?

            I tried doing outdoor pizzas on the same aluminum pizza pan that works OK in the oven, but, alas, it produces, shall we say, a durable crust on the grill. I must find that stone and try another burnout…

            • #17 by Red County Pete on 2015-09-03 - 09:33

              I use a surface thermometer (and a sacrificial steel baking pan). If I can keep the temp below 400F, the crust is good. Much above that, and it’s case hardened. Not going to buy a thermostat controlled grill, though. The old grill thermometer died and replacements peak at 400F, so I have to stay with the surface thermometer. On a good day, it’s great pizza.