Air fryer thermal fuse blown

Discussion in 'General Electronics Chat' started by Peter8519, Apr 12, 2019.

  1. Peter8519

    Thread Starter New Member

    Nov 18, 2014
    23
    1
    Hi All,
    Does this item have a operating life span?
    In other word, once it's blown, just dispose the air fryer.
    Thanks.
     
  2. Tonyr1084

    Distinguished Member

    Sep 24, 2015
    3,188
    792
    Fusible links (thermal fuses) are replaceable. But you need to crimp them into place. Soldering them without super good heatsinking will blow them out. They're designed to fail under two conditions: Extreme heat (beyond their rating) and excess current (beyond their rating).

    I've been finding lately that companies that build and sell appliances are using these links and rating them just slightly above their expected operating range. It's a bad engineering practice unless your goal is to sell more equipment. Mother-in-law had a washing machine blow an FL (Fusible Link). Was going to cost nearly $400 (US) to repair the machine. She decided she would just buy new. OR I could get the entire mechanism and install it myself for $135. The machine was hardly used and just under two years old. But I took the machine home and found that the failure point (the Mode Shift Coil) was where the failed FL was. Two bolts and it came right out. Riveted closed, I drilled out the rivets and opened the coil housing. There was no evidence of an overheat condition. Did some calc's and found the FL was rated for 106% of normal operation. Went to RadioShack and bought one rated for 146% normal operation and installed it at a cost lf $1.98 plus tax. So for slightly more than two bucks I fixed the machine that would have otherwise ended up in the scrap yard.

    Had a similar condition with a neighbors oil filled electric heater. Again, a FL had blown. This is where I learned about not soldering on them. Replaced it with similar but slightly higher and it's been working perfectly.

    NOW: WARNING; NEVER REPLACE A FUSE (OR OTHER SAFETY DEVICE) WITH A HIGHER RATED FUSE.

    That being said, if you know the engineering, and I'm not calling myself an engineer, and you KNOW what you're doing, AND ACCEPT THE RISK, all should be OK. Desk top fans are good examples of FL failures. The motor bushings get dirty and the fan has to work harder to move air, the motor overheats, and potentially causes a fire. THAT is where you DEFINITELY don't want to fool around with ratings unless you're VERY experienced on such matters. You're fryer? Since it is a high temp device, I would advise you replace your FL with a properly rated link.

    Give us the details and rating on the FL. Maybe someone here will have a good solution to the problem.
     
  3. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,743
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    I have had to replace half a dozen coffeemakers because the thermal fuses have blown. I replaced the thermal fuse (from eBay) in one. But in the others, it was too difficult to get at them to crimp. I'm beginning to think it was because I left the coffeemakers "on" with no pot on the hotplate to dissipate the heat.

    Ken
     
  4. Tonyr1084

    Distinguished Member

    Sep 24, 2015
    3,188
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    the wife leaves her coffee pot on with an empty pot all the time. But her coffee maker has a timer. It will shut itself off after an hour.
     
  5. Peter8519

    Thread Starter New Member

    Nov 18, 2014
    23
    1
    Thanks Tony & Ken,
    I will replace one with the same spec.
     
  6. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    My guess is even an empty pot dissipated enough heat.

    Ken
     
  7. MisterBill2

    Distinguished Member

    Jan 23, 2018
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    That warning is always included to cover the seller and maker and reduce the probability of a natural selection event.
     
    Tonyr1084 likes this.
  8. Peter8519

    Thread Starter New Member

    Nov 18, 2014
    23
    1
    Some updates on the air fryer...
    1. Check drawer tray micro switch ... good continuity.
    2. Check thermal fuse(rated 172 deg celsius) ... good continuity. I originally thought that the thermal fuse was the culprit.
    That thermal fuse is hard to get to. It's hidden behind the heat shield. The fan nut is very loose.
    I put everything back together and power on. It works.
    Now, the intermittent problem could be the thermostat or timer and it's not worth pursuing.
    I will get a new fryer.
     
  9. MisterBill2

    Distinguished Member

    Jan 23, 2018
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    I routinely repair those non-reparable items. The last one was a slow cooker, still almost new. It seems that the heater element had failed just past the attachment point. So it was a fairly complete dis-assembly, adjust, and re-assemble, all on a quiet Monday afternoon at an almost empty campground. Fortunately I had the tools that I needed along. It is still working now many meals later.

    So follow the wires and you ought to be able to fix that thing, and avoid more trash into a landfill some place. Also, it is a good education. You will learn what else is inside those things. Possibly another thermal fuse, very well hidden.
     
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