Samsung RS21KDMS – half freezer warm

[Koenigsegg]

Helloes from Sweden.
My Samsung fridge/freezer works fine, except the upper part of the freezer. It sticks to about +5C degrees. Occasionally (the defrost cycle?) the temp changes a little, but as far as I know it stays within 0-(+)10C, approximately. Obviously I have no foolproof way of knowing for sure. (DV camcorder and fast forward play, perhaps ;-j)
The unit has been going for at least 12 hours now, the diagnostics test lights the bottom segment – not the middle one – of the right digit in the freezer temp display. This means the evaporator cover, right? I guess there’s not much in it that can fail except for the fan, so I’m assuming that’s the case. But could anyone with an fault chart tell what the bottom segment means, more exactly? Because I can’t find any problems with the cover right now.

* The evaporator cover fan isn’t rattling, I coulnd’t see much ice there at all. And this is sort of the key thing for me: If I hold the cover so that I can see the fan, and push the door switch, the fan starts spinning. The (whole?) problem is that the diagnostics say otherwise..

* When measuring the components inside the freezer I seem to get almost exactly the readings that previous posts in the forum say I should get(don’t have the exact temperature, but with the door open it must have been slightly below room temperature, +5-15C):
Triple contact to the right:
0 Ohm (fuse?)
244 and 1309 Ohm (heaters?)
6370 Ohm(defrost sensor. I think the value was rising?? Mistaken?)

~5600 Ohm (thermal sensor, ntc)

*The freezer and refridgerator uses the same cooling system, right? So, since the refridgerator is working just fine, no problems at all, I assume this isn’t a cooling system malfunction.

* Power freeze doesn’t seem to make any difference. Could this be because the freezer is locked in a defrost cycle that it can’t get out of? Read somewhere that the temp has to reach +17C for the defrost cycle to end.

* I removed the evaporator cover when I defrosted the freezer. The temperature then reached a bit above +20C. Afterwards I put the cover back in and connected the power. The temp then sank sloowly(several hours, 12?) towards about +5C, where it remains.

* I’ve put all shelves and boxes back in the freezer, “to simulate real life airflow conditions”. My thermometer in the bottom drawer says the temp is even below -20C, which is what I set the freeze temp to. So it’s the upper part, with the temperature sensor, that doesn’t get any of the cool air. That seems consistent with the – alleged – evaporator cover (fan) failure. But like I said above, I can see the fan spinning when pushing the door switch. So this is confusing me.

* I vacuumed the condenser coils.

* When I connect power the fridge temp displays 3(right digit), and the freezer temp displays nothing. The set temps are +3C for the fridge and -20C for the freezer. Does that mean anything?

How careful do I have to be when reinserting the cover(s)? Of course, I’m trying not to break anything, but – theoretically speaking – would misaligning the airflow “connection” holes between the upper and lower covers by say some mm cause my problems? There’s not much room for misalignment, but I can’t come up with much else..
Or.. should I remove the upper cover as well and defrost it too? I’ve left it in place so far, just lifted the bottom of it to get the lower(evaporator) cover out. First time I got the lower cover out it was blocked with ice, not the fan, but the lowermost “exhaust hole”. Sorry, don’t freezer language that well 😉

I’ve worked with electronics for several years, so I feel confident I won’t get zapped doing this. Of course, one should never get overconfident, but I understand what I’m looking at. Otherwise I id it before touching.

I know what the GND and VCC fan connections should be, but FG? Frequency something? If I know what that means I could test the fan. For I really can’t afford like 1000SEK for a cover replacement. I found the fan motor assembly on the net, but that cost 80£(800SEK something) alone 8-[)

Hope all this make sense. All efforts to be helpful are greatly appreciated.

EDIT 1: I’ve reassembled the freezer now, connected everything and put the shelves back in. I held the door switch in and heard the cover fan start(I listened for 10-20 seconds, and it ran for a couple of seconds at a time). I could feel cold air coming from the “exhaust holes” on all 4(5?) shelf levels, so neither cover seems to be blocked frozen?
EDIT 2: I left the f/f running over night, with no shelves and the evaporator cover put loosely into its place. The temperature seemed to fall sloowly below that +5C threshold, but then it rose back up again. Probably when the defroster kicked in.
EDIT 3: I apologize if I’ve given too much technical info. I have just tried to explain my problem in detail to make it easier to give comments.
EDIT 4: Sorry. I forgot to actually add the resistance readings.

[admin]

Re: Samsung RS21KDMS – half freezer warm

Hi

The fault ode you have given is for the fan failure,it may well be that it has failed or giving incorrect resistance to the pcb.

I have had one where the fan ran for approx 30 mins then stopped for no reason.

Is the evaperator fully frosted over when left overnight ?

Bryan

[Koenigsegg]

Re: Samsung RS21KDMS – half freezer warm

Hi.
Thanks for answering.
Here are my ohm readings for the fan:
GRY-YEL 1505 Ohms
YEL-BLK 16.44 kOhms
BLK-GRY 18.93 kOhms

As for the evaporator.. It’s not like everything is covered with ice, but the evaporator isn’t ice free either. The pipes on top of it and the upper fins do have ice on them, but there’s still room between them. So theoretically, if the fan was working, I think – some – air could still pass between them. As it is now, the temp could probably reach -20C too, but it drops so slowly that (No proofs, I’m guessing here) the defroster kicks in and pushes the temp back up.

I guess this is consistent with a faulty fan, especially as you say they might work at first and die after half an hour. But I’m reluctant to give up on it completely, as it is not completely dead. Yet. Is there anywhere I can find out what the FG connection to the fan means? If so I could put the fan/cover in some testbench for hours.

[dpm]

FG means Frame Ground (earth) in anything I’ve ever seen, maybe r600a can confirm.

[admin]

Re: Samsung RS21KDMS – half freezer warm

To be honest..

the depth that you are going to isnt as far as i myself as an engineer would.

switch the unit on and tape over the light switch to see if it is running after a few hours,that way it’ll think that the door is closed even when its open.

Bryan

[Koenigsegg]

Re: Samsung RS21KDMS – half freezer warm

Well.. I wasn’t going to do anything complicated 😳 . Pull the cover out, connect it via some wires to a power supply. But sure, I’ll admit anytime that your way is easier 🙂 . Didn’t think of that. I must have a compulsion to disassemble things.

But will I see if the fan is still running or not? Like I said before, when I held the cover inside the freezer and pushed the switch the fan seemed to run in “bursts”, not continuously. If I tape the switch and check it after some hours, will the fan not moving mean that it is broke or that it has a coffee break?

[admin]

Re: Samsung RS21KDMS – half freezer warm

Hi

If the fan isd running in byrsts then the main PCB will be faulty,I can supply if needed,the fan should run continuosly until the freezer has reached the correct temprature.

Bryan

[Koenigsegg]

Re: Samsung RS21KDMS – half freezer warm

Ok. Those are bad news, indeed. No more replies tonight. (Where this server located btw?? The IP number points to England, but the time stamp of the messages here suggest a ~8 hour difference to Sweden. Never mind, that was off topic)

From what I saw earlier the components on that PCB are pretty standard, but I didn’t look at the fan part, only the heaters. That r600a thing in the middle is not so standard, of course. Thank you both, r600a and dpm. Can’t say desoldering components is my favourite hobby, so I hope it won’t come to that. I’ll get back tomorrow, hopefully. Thanks again.

[Koenigsegg]

Re: Samsung RS21KDMS – half freezer warm

It seems you’re right, r600a :). Found one component on the main PCB that isn’t behaving the way it should. (The cover fan ran fine when in my “testbench”, btw) I’ll try and find a replacement and test the whole thing.

Thanks for the PCB replacement offer, but I simply can’t afford the whole thing right now. Also, I’d expect it to be more expensive than the cover. I guess my PCB is old, Rev 1.1. What’s the current version? The same? Otherwise, any significant changes? Just curious, but noone has to answer this. The main thing is in the other paragraph.

[admin]

Re: Samsung RS21KDMS – half freezer warm

Hi

Going down to component level on the boards we dont do as as field engineers we dont have access to the board config.Also the time to trace down to component level compaired to cost of board isnt ecconomical.

Bryan

[Koenigsegg]

Re: Samsung RS21KDMS – half freezer warm

Hi.
Of course. This is not efficient if done for a living. For me as a private person the situation is different though: If this solves my problem, then my costs have dropped from 80£ initially for a new cover and presumably some more for a PCB to about 2£ for a component(power transistor) replacement. I did this in my spare time. And the advice from this forum pointed me in the right direction. So I just wanted to say thank you. Unless something bad happens(read “drain hole”) I’ll consider this thing closed.

Disclaimer:
** THIS SHOULD ONLY BE DONE IF YOU KNOW WHAT YOU ARE DOING. ELECTRICITY CAN KILL. **

[Author]

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