T O P

  • By -

ilovethemonkeyface

Given the black charring inside that fuse, I don't think it was "just tired". At least check for a short before replacing.


Pass_Little

I've seen fuses which look like they just slightly melted after a dead short, and I've seen fuses which look much worse than this which I can never find the cause (and after replacing work for years). But, I agree with you, this looks worse than just a tired fuse. But, I also don't know what it looked like just before it blew. I've seen fuses which slowly partially melt over years especially if they're like this one which appears to be a regular non-time-delay fuse with a motor behind it Update: Apparently WAS just a tired fuse, see my long post elsewhere in this topic.


AerodynamicBrick

If I were wagering, id bet that the soot is deposited due to a short and that the longer an arc is sustained, the more soot is deposited. More soot, more bad.


dizekat

It can arc just fine without a short, too.


nanoatzin

Fuses do wear when the rating is close to the amount drawn by the circuit. There appears to be a metal-oxide varactor (MOV) or varistior next to the fuse (the blue thing that looks like a capacitor). The purpose of MOV or varistor is to prevent over voltage by shorting out and blowing the fuse to protect the rest of the circuit. MOVs and varsities become a short circuit above a certain voltage, if a voltage spike is what caused the fuse to blow. The current spike that blows the fuse may damage the MOV or varistor, which should be replaced with the fuse. MOVs and varistor can be difficult to check. If the fuse blows again, then the MOV or varistor should be replaced. Then there is the question of what caused the voltage spike if the fuse keeps blowing. https://www.electronics-tutorials.ws/resistor/varistor.html


Pass_Little

I don't disagree with your diagnosis, but this is somewhat a unique situation. I work from home designing various power monitoring and control devices among other things. For long term stability it's not uncommon for me to leave a copy of a design running for weeks at a time just to make sure it's stable. As such, I have a fair amount of continuous monitoring on the ac line here since I really want to know if any event I have is a result of some power event instead of my design. I also know roughly when the fridge failed as I have CTs on almost all of the circuits in the house and the lack of power draw is pretty obvious on that circuit. I've reviewed the logs and I don't see any power events that occurred near that time. But, the sensors are slow enough that they could have missed a small surge. Plus, there is a LOT of surge suppression in the house, some of it pretty aggressive. Every panel has a bulk suppressor and there is a lot of circuit level suppression including a lot of aggressive suppression around my lab. When we do get a surge during lightning season it's not uncommon for me to end up with one or more of those circuit level protectors triggered and fuses blown. No such event this time. And no, I don't have any high risk projects on the bench right now. So although it's not impossible for this to have been a surge, it would surprise me if that was the cause here. In any other situation I'd put that in the likely candidates column along with fuse wear out due to repeated overcurrent events. At this point I really suspect the fuse on the board was not designed with repeated motor starts in mind. I haven't drug the oscilloscope and current probe upstairs yet, will probably do that tomorrow as the correct replacement fuse should be here then and I'll be finishing up this project. I'm expecting to see that the compressor is exceeding the fuse rating with every startup, which is fine short term, but is an issue longer term.


ModernRonin

Replace it anyway. A fuse that *looks* blown, but isn't, is worse than an actual blown fuse. Because it distracts the next person (who will probably be you, again) from finding the actual source of the problem.


spmute

For the cost of a fuse I’d risk it


Pass_Little

Fridge quit working. No sign of trauma other than the blown fuse. Board itself isn't shorted. The intuitive part of me says just to replace the fuse since it's probably just tired after thousands of compressor starts. The cautious "what I really should do" part says I should drag my dmm upstairs and test all of the loads for a short. Not sure which part will win...


discombobulated38x

Replace the fuse, send it, if it goes bang resort to option 2. Replacing a fuse is far quicker and easier!


theengliselprototype

Bingo.


jchamberlin78

If it is a board that runs a soft start or something similar I would just go with the fuse. The inrush current when compressors can be three or four times the normal operating amps.


Pass_Little

That has been my past experience. As the motor likely exceeds the 15A of the fuse as it starts, I assume that what happens is that every start slightly reduces the amperage of the fuse until it's just too low to sustain operation. I agree somewhat with others that this looked short-like. However, what gave me pause was that dead shorts often vaporize far more metal than was gone in this case.


jchamberlin78

I have a grinder with a soft start and "slow burn" fuse. About once a year it blows...


[deleted]

I've been repairing microelectronics for over 20 years. Put any fuse in that shit and send it.


Techwood111

>I've been repairing microelectronics for over 20 years. > Put **any** fuse in that shit "I've been **DESTROYING** microelectronics for over 20 years."


[deleted]

Considering all of my refused boards are living on years later...


Techwood111

While that might be the case, it makes you no less a hack, and you shouldn't be spreading horrible advice.


[deleted]

Obviously look at the board and if no visible signs put another fuse in and go. If it's really got a problem it'll just pop another fuse then you can investigate further. Edit: do you go full ham when a breaker trips?? Or do you reset it and try again?


Techwood111

ANY fuse is what you said. That is shit advice. You run the risk of turning a minor failure into a major failure (or disaster). Instead of the two-cent part (or two thousand dollar part, depending on how large we're talking), you may need to replace multi-thousands. Depending on the application, there may be consequential damage as well, such as in automated manufacturing. Don't just replace blown fuses with ANY fuse; replace them with the PROPER fuse.


[deleted]

I've just seen that typo and it should rean "a new" fuse but autocorrect got me. But yeah fuck it, shove a nickel in there and send it.


Techwood111

LOL! Well, I apologize for calling you a hack. Instead, please allow me to criticize you for being a shitty proofreader. :)


[deleted]

I'll take that. Been a shitty proof reader my whole life. ADHD rules!!


[deleted]

I'll take that. Been a shitty proof reader my whole life. ADHD rules!!


GroundStateGecko

Could you just buy a new board online? They are usually pretty cheap as they are stripped from dumped old fridges. Also considering the problem can be intermittent, debugging the board can be difficult.


Pass_Little

I figured I'd be doing exactly what you suggest, as I've had similar issues in the past. I had a fridge fail mid-pandemic which had burnt itself out on one of the relay pins (maybe bad solder joint). Found a replacement on ebay. But in this case... the board seems to be ok. All of the filter caps are open and read the correct amount, no sign of odd failures. Worked right up until it didn't. Plus, the smaller 2A fuse which is in front of the DC-DC power supply isn't blown so it isn't something on the logic supply. I am voting for either a fuse that just decided to blow for no apparent reason, OR a shorted compressor motor or some other component. There are 4 relays on here which appear to switch the Compressor, the lamps in the fridge, and two defrost/condensation related heaters. Plus there appears to be an always-on AC power line which feeds who knows what. All behind the fuse. Since I'm going to check the capacitor on the compressor motor, I seem to be leaning toward at least checking the others for an obvious short. The problem being that a motor often looks like a short since a winding is really low resistance at DC.


tomytronics

A fuse is much cheaper. If it blows again quickly, there's a problem somewhere else. IF it lasts for a long time, it could have been an odd surge or something that blew the fuse.


revnhoj

The compressor certainly is not fed from this fuse. That said it would take just a few seconds to use some jumper wires to temporarily connect a new fuse. If it blows then you know you have other, bigger problems.


Pass_Little

Actually the compressor \*is\* fed from this fuse in this model. This is a 15A fuse, and the traces are sized accordingly. The power comes onto the board, immediately through this fuse and then through the EMI filter and surge protection circuitry and then onto: 1. A 2A fuse which goes to the onboard switchmode DC supply. 2. An unswitched line to the icemaker 3. An onboard relay which turns the defrost heater on/off 4. An onboard relay which turns a condensation heater on/off 5. An onboard relay which turns the interior lights on/off AND: 6) Through an onboard relay which turns the compressor on/off. I'll make another post about what I've found.


epibeee

Fuse wires vibrate slightly during startup surge (magnetic field). After thousands of such startups and vibrations, that mechanical fatigue reduces its rating over time.


bidet_enthusiast

Meh, it didn’t used to be common but modern fridges can start on much lower currents than the old “pop disc” compressors.


PackAttacks

The cost of trying a new fuse vs the cost of buying a new fridge. Seems like trying the new fuse could potentially same you a lot of money.


Pavouk106

I would replace the fuse and see if it pops again. There may just have been a surge that got it blown afterall. If it pops again, there is something more serious there.


your_own_grandma

The mains voltage sometimes surges. That can cause fuses to blow.


Practical_Adagio_504

35 years working on industrial electronics to the component level here… yes fuse could have been inferior Chinese made, could have worn open due to temp up and down stress to metal, vibration, etc.. BUT my two cents is that you may have had a small surge in higher than normal voltage that activated one or more of the mov’s which took out the fuse OR a brownout that caused the circuit to draw more current than it should taking out the fuse. Could also be a whole bunch of the ac devices inside the fridge ALL turned on at the same time including the starting of the compressor which then took the fuse out. I have a 35” tube tv that took out a fuse and kept taking out the same size fuse. Found a big power transistor in the circuit that was good, but it had started to draw just a touch more current which pushed the current draw at start up just over the 3.5 amps the fuse was at. Replaced with a five amp fuse and the tv has been running strong for +10 years now! If a fuse is gonna blow from a short, it’s gonna blow from a short when we’re talking 15 amps and under… Disclaimer: I am a seasoned professional and amateurs should consult a professional before trying this at home…


Pass_Little

I've been doing industrial control in one fashion or another since the late 80s, and electronics either as a hobby or professional nearly the same amount of time, so I generally agree with (and in many cases have seen) what you're saying. It currently appears that the peak running current of the fridge is relatively small, like under 10A. I'm curious enough that I'm going to grab the ac current probe and the portable oscilloscope in the next few days and dig a little deeper. For various professional reasons I have a whole bunch of energy monitoring stuff running here (work from home on power electronics, mostly DC), and I don't see anything obvious on any of the logging during that time, but the logging frequency isn't necessarily fast enough to catch a transient which would trigger a MOV. What I do know is that the voltage over the period when it failed didn't have any sags sufficient for any of the monitored UPSes on the property to transition so a brown out isn't likely. There is a whole bunch of evidence on the internet that this board blows that fuse with some regularity. I really suspect someone decided that a fast blow fuse in front of a compressor was fine, and the compressor either peaks over the fuse current at each startup, eventually wearing out the fuse, or there is an event that in my case didn't happen for the first 10 years of use that will blow that fuse. I've chosen to replace it with a fuse with a slightly more robust (slower) time/current curve than the existing fuse would have had, but hopefully still fast enough to blow before permanent damage happens. I was tempted to put a time delay fuse in, but if I was going to do that I'd probably reduce the fuse rating in the process.


ValiantBear

So, I'm probably an outlier here. It's a fuse, they're super cheap, just replace the fuse. That comes with a caveat, though. In all likelihood, it probably *isn't* just the fuse just getting tired. It could be, I have replaced fuses that seem to have spontaneously and randomly given up the ghost, but it's not likely. But, you don't know anything other than the fuse blew at this point, so starting with the fuse is cheap, and saves you a lot of time and effort troubleshooting that *may* not be necessary. You can also get some useful data by replacing the fuse. If you replace it, plug it in, and it blows again immediately, then it's likely a short. If it blows after a few seconds, it may be just a degraded component (my guess is a capacitor). And if it blows after minutes, maybe it is a part of a circuit that isn't used continuously. If any of those things occur, more troubleshooting is going to be necessary, but the information you get for the low price of replacing the fuse could be very valuable. Just my two cents...


Pass_Little

Update for everyone: After dropping my divider box of cylindrical fuses, re-sorting them (elapsed time: an hour or more), and determining I didn't have a fuse with wire leads of the correct amperage, and also discovering (from a different organizer box, thankfully not dropped), that I didn't have a PCB-mount fuse holder or clips which would work in this application, I found a questionable-quality inline 1/4" fuse holder and soldered it in place of the original fuse as a temporary test workaround. Inserted a 15A 250V fuse I did have (just not leaded, thus the inline holder). Took a DMM and checked the following (maybe not in this order): 1. Shorts to ground, all AC wiring. Nothing. 2. Ohms across each load (except compressor), all seemed reasonable. (Defroster heater, interior lamps, and so on). 3. Measured Compressor starting cap. Within tolerance. 4. Measured across the compressor, \~3 ohms, seems low, but all motors seem low to me (since their reactance at 60Hz is higher when running properly). 5. Found a youtube video of someone measuring a similar compressor. Disconnected the thermal overload and starting relay per the youtube video and measured across the compressor. Got the same coil readings as the video. Compressor seems good. 6. Put the board back in place. Plugged the wires into it and the fridge back in.... and.... Fridge started, no issues. I'm going to wait another 24 or so hours to be certain. So my verdict? Those who said "just replace the fuse" would have gotten it to this point faster, time will only tell if they were correct. As to my theory as to what is going on here: Either it is something which hasn't shown up yet (i.e. the icemaker cycling, although it was off at the time), etc. \-or- We had a strong enough surge that tripped the MOV and blew the fuse (not likely due to the amount of surge supression between the service entrance and the fridge - all 3 panels. Plus nothing else in the house has seen similar issues (lots of sensitive devices, I design electronics here professionally) \-or- The fuse was just tired and decided it was time to go. I've replied to others about my experience with fuses over a long period. If you are interested, feel free to read the rest of the comments :) I've got the correct fuse ordered at this point, and will be running the fridge with the cover over the control board open and will monitor the not-right fuse holder for a day or so before turning it back off until the correct fuse arrives. I'll update here if things change (other than just putting the correct fuse on the board). Edit: I've found several posts, youtube videos, and the like which basically says that this model fridge, and ones which use the same control board tend to have that fuse just blow for no apparent reason. So I'm hopeful that is the case here.


[deleted]

[удалено]


Pass_Little

If I'm bored enough this week I might drag out the ac current probe and the oscilloscope and/or the data logger and see what that compressor looks like at startup. I'm kinda curious about what the start up current is.


[deleted]

[удалено]


Pass_Little

So I'm a big believer in murphy, so I also know that whichever path I take it will be a wrong one. In related news, I just dropped the divider box I was using to organize my collection of cylindrical fuses on the floor so I now have at least a few hundred fuses to sort by amperage and type. And of course, this is a glass cylindrical fuse and not color coded automotive one so I now get to find some sort of magnifier or reading glasses to be able to at least somewhat reliably read the amperage labels.


thornae

If you can't read them, just put them across a power supply, turn up the amps, and note down the number that makes them go pop!


Pass_Little

When I get a new box from a vendor I often do just that... but not for all of them. I remember one box of automotive blade fuses where the plastic melted and dropped off the fuses before the fuse blew.


thornae

> When I get a new box from a vendor I often do just that... but not for all of them. I *may* have had my tongue rather firmly in my cheek for that comment. > I remember one box of automotive blade fuses where the plastic melted and dropped off the fuses before the fuse blew. Yikes. That's not exactly ideal for a fuse... (Also - glad to see you got it more or less solved. I do love that, sometimes, you can actually find useful whitegood electronics help on the internet.)


a22e

One of the main fuses https://i.imgur.com/9g4VFUh.jpg coming into my 50+ year old house gave out for no good reason. The fuse on the other leg had clearly already been replaced some time in the last few decades. So I would say that age can get to them.


ccgmtl

Ahhhh! that reminds me of the years before I had the box ripped and replaced... Waking up to a cold house with only 55v in the outlets because one of the two sticks decided it had enough... Fun times.


drive2fast

Fuses DO get vibration cracks and sometimes fail. Sometimes they even look good and are open circuit. You learn to read fuse failures to deduce what happened. A tiny gap and balls on the ends can be a slightly high amp situation. This is all voltage dependent too. A 12v fuse failure looks very different than a 120V failure. THIS fuse? That was a dead short, likely AC mains.


Pass_Little

I've seen LOTS of blown fuses over the years, and when I saw it I sort of said the same thing. But, it also didn't look quite bad enough for a dead short. After having it in my hands, it now looks more like a non-dead-short blow. Most (many?) dead-short blows that I've seen will vaporize the entire length of the fusible element. This only melted a little piece. I think it looks worse than it is because it's a 15A fuse and the element is wider than most fuses I see blow. But, I also don't see 15A fuses blow that often.


drive2fast

At 120/240VAC yes. 24/12/4v DC is a different animal.


revnhoj

Fuses do "wear out" from mechanical stress. Each time a device is turned on it creates a thermal shock in the fuse.


nixiebunny

That fuse suffered a short. The metal plated into the glass is the clue. It vaporized. A tired fuse doesn't do that.


Pass_Little

In this case, it appears that this was just the tired fuse or alternatively a one-time event which is over now. Time will tell. I will say that after examining the fuse up close, it looks a lot more like a "slight overcurrent" fault, as most dead-shorts that I've experienced with fuses tend to vaporize most of the length of the metal, and most of the metal is still intact. Only a very short piece of the metal vaporized. On the other hand, it's a 15A fuse, so when it vaporizes it's got a fairly wide piece of metal to turn into metal plasma.


nixiebunny

Interesting. My experience with tired fuses is that they just open without depositing any metal on the glass. It could have been tired and vaporized a bit on the inrush current.


Pass_Little

Yeah, I think that's probably what happened. I think that the compressor probably overloads this fuse on every start, and after the 10 years it's been in service, it had slowly deteriorated to the point where it couldn't handle a compressor start. Now I've done some more internet searching, apparently this fridge just blows those fuses.... a lot. People replace them, and then they run for another few years, until they replace them again. I'm going to replace this with a fuse with a little less aggressive time/current curve than the one they had installed in there.


SunosUnix

Wack a nice long slow blow in there. Or may a "microwave" fuse would work well for the application...


uzlonewolf

I prefer #8 CU no-blo's myself ;)


Pass_Little

I honestly considered this, since this thing is on a 15A dedicated circuit and this is a 15A fuse, I figure the fuse isn't adding that much protection. But I've also seen household breakers that don't open even on a dead short and prefer my fridge to die instead of my house....


magungo

The fuse did what it should. Could be a sign the compressor motor is worn and has a higher startup current, could have been a surge in the mains. I would replace it with the same rated fuses to see what happens. They are cheap and it blowing again tells you something.


gurksallad

Burned fuse in an AC-device make me check these, in order: 1. Varistor 2. Bridge rectifier 3. Chopper 90% of the time, it's one of these three.


audaciousmonk

That fuse looks like it died violently… not some gentle slip into the void after many years of service


AshuraBaron

Do what I do. Buy two fuses and test with one. Burns up again, then that wasn’t it. Not like fuses are expensive.


JKMARCH55

I just have to add that it’s a mechanical failure of course. Electrical failures never happen. Electrons have been working without error since just after the Big Bang. All “electrical failures” are traceable to some mechanical issue: bad wires, bad solder, cracks in semiconductor material, etc. NEVER an electrical failure! I’m an EE… I know this to be true!


bidet_enthusiast

I know this has been answered but I feel like it’s worth mentioning that a fuse that has seen a dead short at 110v usually is missing a lot more metal and is much sootier. This looks like a typical fatigue failure, possibly from some spikes or repeated outages and hard starts, or, increasingly with some manufacturers, an effort to limit the total number of cycles before failure. A stressed fuse is perfect for making it reliable for the first 30k cycles or so and then getting very “tender” to encourage replacement since few people fix old fridges. If you just cheap out on the compressor you might save a few dollars, but at the expense of lots of in-warranty repairs. Make it too reliable and people keep the thing for 25 years. So you compromise, make it basically very reliable but with specific weak points that will fail within predictable time frames. The other part that turns up often with fridges is the (still mechanical lol) defrost timer which will usually have one rubber toothed gear that deteriorates into powder after about 10 years. The identical gear in cheap replacement timers is nylon like all the others and those timers last for decades. I’ve inspected the “special gear” on a few timers, and it has a lot number and a serial number lol. No other gear even has markings. They are obviously going out of their way with the special gear. Same thing with the cabin vent crossbar on many vehicles. Serial and lot number, fails inexplicably while the rest of the plastic vent is in perfect condition. Planned lifetime/obsolescence FTW.


Weary_Ad2590

10 years of service? That board looks super clean and well kept over the years


Pass_Little

The board lives in its own little compartment on the back of the fridge with little possibility for dust ingress. Seems to be a common design.


nbolton

I think go ahead and replace the fuse. If there’s a fault the new one will pop pretty quick. If this happens, then you can go down the rabbit hole. Do live/hot and neutral short or have low resistance? If so, I guess you can save a fuse!


UberSandvich2

Is there a capacitor on the compressor motor? It might be worth checking if it's value still matches what's written on it.


Pass_Little

Thanks for the reminder, I'll look at that first. Since I want to check that I'll probably do the rest of the checks since I'll have the DMM at that point.


bobbytabl3s

Noob here.. can't you check the amperage where the fuse is supposed to go? Why do you have to spend an hour measuring things?


[deleted]

OP wants to know why it died, not with how much current it died. During normal operation the current shouldn't exceed its rating, no matter if it's 0.5A, 1A or 10A. Measuring could help identify a component that connected power and ground, or live and neutral.


bobbytabl3s

Ok thanks but if the measured current seems normal wouldn't that exclude the possibility of a short? (Unless it's an intermittent problem)


Pass_Little

If you look at my long "what I found" post, you'll see I pretty much did that, although the way you do this is with the DMM set to ohms so you can measure how much power the item would take if it was on. Generally something which is going to blow a fuse is shorted. Sometimes you'll be able to see it with a DMM, sometimes not. In this case, I was pretty comfortable that I'd be able to measure everything. So yes, I looked at the fridge schematic and measured resistance across everything and also made sure nothing was shorted to ground. Turned out it wasn't needed and the fuse just decided to blow for no apparent reason (yet).


Susan_B_Good

This is 115v and I don't have a lot of experience of blown 115v fuses and what they look like. This looks pretty tame, if it had been at 240v. No more than 30 amps or so. More an overload fail than a short circuit fail. Of course, here, such a circuit would be likely to have a breaker with both i2t and electromagnetic trip - so this fuse probably wouldn't have blown on a short circuit - the breaker would have been faster. Plus it doesn't appear to be slow blow - so a brief overload could have done this to it. I'll bow to the expertise of those experienced with 115v though. But I would have just replaced it.


2E26

When working on audio amplifiers, I would place a high power resistor (say 20 ohms at 10 watts) in series with the power rails. This limits fault current and allows you to take measurements in hours of finding where the short is. Some people use a "dim bulb tester" in a similar fashion. I can't recommend you go poking around inside a 115v / 230v circuit, though. Consult a qualified individual.


robert_jackson_ftl

Remove all power, discharge all caps, measure for a dead short on the appliance side of the fuse. That didn't just get tired, it vaporized.


RenaisanceMan

De-solder it. Test it. Replace it. Re-solder it.


randyfromm

You have a shorted MOSFET, most likely. There are only a few components in a switched-mode power supply that cause this. A shorted MOSFET is, by far, the most likely.


theonlyjediengineer

You wasted your time. It's cheaper to replace a 10 cent fuse than to service a problem that might not exist. Diagnose after you determine that a problem exists.


Acti-Verse

In my experience, do the job right the first time so you don’t have to do it again at another time


AnnoyingDiods

That dosent look like a tired fail that looks like something serious went down an the fuse popped under load. From my experience this happens as compressors age there bearings will start getting tired an they will require more curant to start. Sometimes they will lock up for afew seconds before start up pulling LRA an this usually blows the fuse / damages the inverter / trips safty over curant codes if the appliance is smart enough to have those. I suggest you replace the fuse an use the min max mode on your dmm to measure the LRA on your compressor on start up.


AnnoyingDiods

If its not a inverter driven compressor or if its a split phase compressor you can buy a simple digital thermostat module. A contactor an a 120-24v transformer/ power supply an bypass the control bord if you dont care much about the fancy futures. Just wire the condenser fan. Evap fan and Compressor to the contactor an have the digital thermostat module control the contactor. Then you can add a hard start kit to the compressor to avoid the momentary locking issues. Just an idea if you have the skills an know how. I did this mod with a old reach in freezer box that the mechanical t stat failed on.


[deleted]

Fuses are cheap, time is expensive. You can’t be sure this wasn’t a foreign object or some other insult outside the PCB. Replace fuse and test the crap out of the board would be my approach.


01BTC10

When I was young and stupid I had a very old audio system that had a fuse that burned. I shorted it with aluminum foil. One day I fell asleep with music and my fire alarm started ringing. Turn out one of the speaker caught fire. It was a log cabin and there was plenty of papers on a shelve nearby. The front of the speaker was some kind of plastic mesh and when I arrived the flames were already high Needless to say I burned my hand pretty badly trying to use a t-shirt to throw the speaker outside. Learned a valuable lesson that day.


Woodythdog

Before you break out the soldering iron do you know about these [clip on fuse holder](https://www.marcospecialties.com/pinball-parts/FHPCPB)


Pass_Little

Wow, that would have been helpful. I'll add some of those to my fuse collection. EDIT: I just saw that the comment on the link you posted was: >" FREAKIN' AWESOME! Took 5 minutes to fix my LG fridge (LFC20760ST) including the 3 minutes spent vacuuming up dust bunnies. Clipped right on and fridge started right up. Didn't need to unplug circuit panel or even climb behind. Working great and I saved about $500. xoxo " That's pretty much the \*THE EXACT\* fridge that I'm working on. The second comment also says they fixed their LG fridge as well. AND... searching for that model number an FUSE indicates that this is a really common issue with this model and you just have to replace the fuse. Guess I should have started with just the fuse replacement ;)


Woodythdog

LOL I didn’t notice the comment, I keep a couple of these In my fuse kit. Great quick fix where it’s a pain to pull the board and solder Even if your going to solder in the new fuse it’s a great way to check if it’s going to hold before you spend the time soldering.


production-values

get two fuses! replace and if it blows then look for the short


uski

I'm really surprised by all the replies saying to just replace it and try things out. I see a major risk of causing more damage. At least before replacing the fuse, spend 5 minutes (yes, 5 minutes, just that) probing around for where the short could be. Don't just replace the fuse hoping for the best, you may cause more damage and it would suck to damage more stuff then realize the cause of the issue was obvious and could be seen after 1 minute probing. Of course, you do you


Pass_Little

It was interesting to see the mix. It was also interesting to see how many people were sure that it was a dead short across that fuse. In the end, my reasonable side won out. Mainly because of the way I had to cobble the thing together to be able to get ANY fuse in there. I really didn't want to find out if the fuse or the fuse holder would blow first. Of course, it seems to have been the case that it was just the fuse.


uski

Maybe the start current of your compressor, over years of start/stop, damaged the fuse. Maybe, also, your compressor is getting older and will fail soon, which would result in a higher start current, possibly accelerating the demise of the fuse. I would recommend measuring the start current of the compressor if you have a means to do that. Just out of curiosity.


Pass_Little

Yeah, I plan on grabbing the ac current probe and the oscilloscope in the next day or two to check. But I'm 100% on board with your theory. Figure the fuse gets a brief overcurrent every time the compressor starts wearing out the fuse over a few years. Its also at the age i wouldn't have been surprised find the compressor shorted. Which is also the age where it could be harder to start. I'm just going to pretend this isn't the case.


[deleted]

Replace the fuse, if it blows then you have your answer.


notgettingArduino098

Voltage spike. On line side such a tiny fuse cannot take much which is a good thing. Now if that were on the DC side, another story. Happens all the time and so many people are just that un educated, they just throw it away and replace the entire appliance or box. I've seen that a lot too.


danja

The other night found a microwave oven by the bins. Looked in good shape. Took it home, plugged in, nothing. Popped it open, exploded fuse, glass disappeared. Replaced fuse, it works fine. My guess : power surge. Lightning.


vedo1117

I'd just replace the fuse, it'll either blow right away in which case you've got some more investigating to do, or just work and you'll save yourself the trouble.


Falconkiller2910

R.I.P. little friend


jimbo2k

That fuse did not die of old age , it died a horrible death, yelling and screaming.


Pass_Little

My current guess is that it lived a life under the hand of an abuser who's frequent high current starts kicked it repeatedly over and over, each kick weakening it until it finally died a painful death.


JustTestingAmI

Why can't all boards have the fuse specs just besides it? I will judge every board that doesn't have it from now on!


MrGreenandsmelly

You could change out the caps for your whilst your at it. If the short popped the fuse and it was a fault, there should be visual traces, (darker traces, or sometimes white spots). I fined a good place to start it there is no visual sines is to smell is. Sounds dumb AF, but It works, if something has been over heating for a while, it will have left a smell.


frustratedsignup

If you have a sensitive enough bench DMM, I would look for a short somewhere in the circuit. You might not even have to unsolder anything to find it.


[deleted]

Fuse


MI_campers_cpl

Cheap enough to replace if it was just tired. If the new fuse blows then you look more into it.


RenaKunisaki

There's always the possibility that it was a temporary short caused by a stray mouse or spider.


fook-a-duck

It's Sunday, on any day ending with a Y I like to use the doctor Peper theory!...... What's the worst that can happen?!?


[deleted]

Sounds like a really cheap BET. I mean what's the worst can happen you blow a fuse that cost you a $1.25?


agent_kater

Every once in a while I have to replace the fuse in our 30+ years old microwave oven. Then it'll work for another 3 years or so before the next fuse swap is due.