Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

[CapLeaker]

A few days ago my Kenmore Elite Fridge, Model # 596.77533600, quit dispensing water and ice. The display on the fridge was still working, the micro switch on the dispenser tested good, but it was intermittent dispensing water. Mostly actually it was not. Really weird. Sometimes it would dispense water and ice with the right fridge door open, but not when closed.
After a while I came to the conclusion there is trouble on the main HV board on the back of the fridge. The HV control board # Maytag 12920710. Nothing out of order when you look at it. Then I began banging on the relays, but that wasn't the problem either. Took the HV board out and started testing capacitors. On mine there is a Ltec branded 35V 270uF cap in position C14. That cap looks like brand new, no bulges, no leaks but measured a whopping 14.5uF with an ESR of 408 Ohms! Changed that sucker out and I've got a working fridge. A 60 cent cap saved me $300 for a new board, or $2600 for a new fridge.

[stj]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

so c14 is Ltec but they used a couple of pana FK's too??

[CapLeaker]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

yeess... look at the relays on my pic too...

[CapLeaker]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

I've totally recapped that board this morning. All of them were bad out of circuit besides the 2 Panasonics. The Elna starter cap was creeping up on ESR as well.

[stj]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

lower-right,
the 1n4007's look like they have corrosion on the legs where they enter the body??

[momaka]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

Nice fix!

This is the reason I am not going to get rid of any of our old appliances in our house. They are from the early 90's - a time before all of this cheap electronics crap got into everything.

[CapLeaker]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

lower-right,
the 1n4007's look like they have corrosion on the legs where they enter the body??

It seems like that stj. I saw that too. This pic was taken before I did anything to the board. I did clean that up.

Something else: This board has a mixture between Elna, Panasonic and Ltec caps.

[CapLeaker]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

Nice fix!

This is the reason I am not going to get rid of any of our old appliances in our house. They are from the early 90's - a time before all of this cheap electronics crap got into everything.

The only 80s and 90s devices that I still have are my old ham radios, a NES, a C64 and a Tektronix 100MHz oscilloscope.

[kc8adu]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

the last 2 i repaired had cracked solder under relays,transformer,and heatsinked parts.
they just had to throw in some crap to ensure failure out of warranty.

[stj]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

they just had to throw in some crap to ensure failure out of warranty.

i think they teach that in design school!
my favourite is putting a startup cap against a transformer or heatsink so it runs for years till someone unplugs the equipment or loses power.
then it's dead, because the remaining capacitance is coupled to the device temperature!

[momaka]

Re: Kenmore Elite Fridge Water / Ice dispenser not working, Maytag 12920710 (fixed)

i think they teach that in design school!

Not really.
Most schools don't teach shit... or at least not if you don't care enough to learn. Though, I suppose that doesn't apply everywhere. Perhaps the top schools/unis are a different story. But where I went, most people would easily get by with just copying/cheating. Actually, at least half of the EET students in my classes were like that. You'd be surprised how many people get an Engineering degree just for the prestige and/or expectation of a high salary.

Then when they get a job, that's where they learn everything on the spot.

So all in all, school hardly matters much. Also, I think these days most designs are computer-generated anyways. Only then a few humans tweak the design before it goes out the door. Once out the door, the bean counters at the top make a marginal design even worse by subbing many parts with cheaper ones or removing them altogether.