Get Answers to your Appliance Repair Questions

Washer Parts  ·   Dryer Parts  ·   Refrigerator Parts  ·   Dishwasher Parts  ·   Range/Cooktop/Oven Parts  ·   All Appliance Parts 

Author Topic: Freezer in Samsung RSG257AARS side-by-side wont freeze  (Read 3337 times)

Offline danube

  • VIP Member
  • Member Since: Oct 2016
  • Posts: 9
Freezer in Samsung RSG257AARS side-by-side wont freeze
« on: October 11, 2016, 11:14:27 AM »

Hi all,

I am new here, and just registered to try to ask some questions so I can repair my Samsung RSG257AARS side-by-side fridge. The fridge works, but over the past month or two the freezer stopped freezing. I have no fault codes on the front panel, but it ALWAYS reads -14F and 34F even though the freezer is most certainly NOT that cold.

In forced cooling mode, the vent closest to the freezer evap coils gets to about 18 F overnight, and the fridge gets to about 28F overnight. The overall fridge temp is about right, the freezer is above freezing.

I am beginning to suspect 1) a bad sensor, and 2) stuck 3-way valve. So, questions: In forced cooling mode, if the controller really thinks the freezer is at -14 F, will it ever force the 3-way valve to cool the freezer side?

A month ago I checked the freezer main compartment sensor and it was within the correct limits. Could the defrost sensor and the ice maker sensor be contributing to the wrong reading, or is this a controller problem?

I would like to force the 3-way valve to the freezer side and then force a cooling cycle to determine if the compressor and refrigerant system is sound so that I can decide if it's worth fixing this fridge. How do I do that?

I see "option codes" can be set in other models to force the 3-way valve. How about in this one?

If my 3-way valve *is* stuck in the fridge position, the flow diagram in the fast-track repair guide shows that the fridge and freezer evaporator coils are in series. Why is this set up this way? How cold should the freezer get if the valve is in the "fridge mode"?

So, any help from people with experience with this fridge would be greatly appreciated. I'm hopeful I can fix it if I can learn a little more about how it works. By the way, I have the knowledge and skills to fix this thing, I just need some more information as the service manual is pretty vague and confusing and covers 5 models at once.

Thanks!

Dan

Offline Patricio

  • Technician
  • Member Since: Aug 2011
  • Posts: 527
  • Country: us
  • Tight Lines
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #1 on: October 11, 2016, 09:25:58 PM »
If you have the fast tract you would read that the diverter valve only shuts the flow of refrigerant to the Fresh food, otherwise the flow of refrigerant is goes to fresh food side 1st then continues to freezer evaporator.  If valve was stuck in closed position the fresh food would be warm.   sounds like you have a refrigerant leak if the freezer is not down to temperature.

Is your ice maker making ice.  if it is the freezer is fine.  Put a thermometer in both compartments & observe temperatures.  Don't trust the display for actual temperatures.

Finally study the fast tract.  All the information is there to diagnose your refrigerator for proper operation.
Great Old Fashion Hometown Service

Offline curjones

  • Technician
  • Member Since: Nov 2013
  • Posts: 340
  • Country: us
  • Service Tech, Owner
    • Buy me a beer through paypal
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #2 on: October 11, 2016, 11:23:31 PM »
Checking out your post I saw this one right below in similar related topics.

I would be inspecting frost pattern on evaporator, and then also do voltage test on the thermistor, defrost sensor.

hope this helps

http://appliancejunk.com/forums/index.php?topic=16283.0
About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack(diet coke in my case) . The small green square=personal message.

Offline curjones

  • Technician
  • Member Since: Nov 2013
  • Posts: 340
  • Country: us
  • Service Tech, Owner
    • Buy me a beer through paypal
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #3 on: October 11, 2016, 11:32:24 PM »
 I have no fault codes on the front panel, but it ALWAYS reads -14F and 34F even though the freezer is most certainly NOT that cold.

That part sounds like a faulty sensor.

how did you test it?  Ohm out the sensor, or voltage test.

you said (I believe I read) sensor is in specks, what did it read?

and like Patricio said you have to know what the actual temps are, to know if sensor is reading actual, in specs off chart
« Last Edit: October 11, 2016, 11:33:41 PM by curjones »
About the icons: The beer is tip link, if a tech saves ya some money buy em a 6 pack(diet coke in my case) . The small green square=personal message.

Offline danube

  • VIP Member
  • Member Since: Oct 2016
  • Posts: 9
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #4 on: October 14, 2016, 12:11:05 PM »
Hi all,  Below is what I cross-posted to the yahoo appliance repair group.   
--------------------------------------------------------------------------------------

Hi all,

  I've done some more troubleshooting.   Last night, I pulled each of the sensors of the freezer, one at a time, with the fridge running, and "ohmed them out".   I measured the temperature at or near each one with a thermocouple.   The freezer chamber sensor and the defrost sensor were reading roughly correctly and were indicating in the mid 60's, consistent with the fridge being warmed up to nearly room temp.  Both read about 6000 - 7500 ohms.   The ice maker sensor was anomalous.  It was reading about 14 KOhm indicating it was 28F.....  Can't be right.  But maybe in the depths of the (empty and warm) ice maker it was still cold?   But in ALL of this, the damned temperature of the freezer as reported by the control panel was -14F!   This is CLEARLY wrong.   

   If I do a diagnostic scan with any of the sensors pulled off, the front panel reports it.  So the CPU knows when a sensor is totally bad.  It also correctly detected the disconnection of the freezer fan.

I took out the main PCB and inspected if for cracks and trace shorts.  Found nothing.  Put it back in and lo and behold the freezer temp now reports at 61F!!  So, something is up with the main board.  It seems to reset itself when the power is off for a while.  Note, there are a bunch of reports of this sort of behavior on the internet, with regard to this fridge.   I am willing to bet the main board gets screwed up by brief power failures, and those errors are cumulative.  But there is no nice way to solve this.  There is no reset button on the board.  You have to unplug and warm up the fridge.

I left the fridge running overnight, set point at -8 for the freezer.   In the morning, the freezer reported -8 on the control panel, but the temperature at the output of the freezer vents was 34F, as measured by a thermocouple.   Somehow, the controller is still not reporting correctly.  I measured the sensors again, in situ, measuring voltages this time.  They were:
ice maker  2.86V = ~31F
  freezer    2.76V = ~36F
  defrost    3.64V =  3.2F

...so all are perfectly consistent with reality, even the defrost sensor, as it's right on the coils.  So the coils at least are getting to near zero.    Control panel still reports -8F.  WRONG!

  I unplugged the fridge AGAIN.  NOW the control panel reports 32F!!  So, it seems that power cycling the main board resets it and it reads correctly initially, but at some point it fails to track the changing temperature correctly.

   I viewed the "load options" displayed by the control panel in diagnostic mode while "forced cooling" was on.   Observation 1:  The manual is simply wrong.  The "load status" key as shown in the manual for the RSG5K/F/D and RSG257 fridges use only 2 digits.   My fridge is displaying on 3 digits!   If I follow the key for the RSG5V and RSG5B fridges, then the displayed segments make sense.  Observation 2:  If I understand observation 1 correctly, then even though the freezer is too warm, and the fridge about right, the main board is still keeping the step valve in "fridge step valve on".   So, the freezer is not getting maximum cooling.  This is true even with "power freeze" turned on.  Maybe this is intended.   Maybe the main board makes sure the fridge is cooled first and after some long delay it switches to the freezer.  Or maybe this is another sign the main board is defective.   I don't think I will ever find the answer to that.

  So, I am going deeper.  I connected a stepper motor controller directly to the stepper valve at the main board header.   I think I have connected the coils correctly, and I can drive it in one direction and after some steps it makes a stuttering sound, and then drive it in the other direction, and after some steps it also makes a stuttering sound.   So I think I have convinced myself I can drive it back and forth between one state and another all the way to the end of travel.    I am going to see how fast and how deeply the freezer cools in both states in forced cooling mode, with the compressor on full.  That should tell me if fundamentally the fridge is sound, and I will report on that later.

  But, for the experience of those here, do my temperature measurements and the resetting of the main board readings point to a defective main board?  Or is this just the way the thing works - a bit quirky?  I can get a new one for $135 or so, and it's an easy swap.   I still don't want to waste money on it if the fridge won't cool, but it sure looks like at the very least I will have to replace the main board. 

  Suggestions?

  Dan

p.s.  In all of this, I have ignored the fridge side, which seems to be holding reasonably closely to what the front panel set point is.  The food is cool.

Offline baldwinappliance

  • Technician
  • Member Since: Feb 2014
  • Posts: 198
  • Country: us
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #5 on: October 14, 2016, 11:35:30 PM »

I would be inspecting frost pattern on evaporator, and then also do voltage test on the thermistor, defrost sensor.

http://appliancejunk.com/forums/index.php?topic=16283.0

All that work and reporting makes my head spin...go to the basics...do you get a frost pattern on the freezer evap?

I think most units default to displaying the set temperature because if they displayed the actual temp they would generate a bunch of warranty calls every time someone brought home a new case of beer...wha the...why's my fridge at 45 degrees?!? I want my beer cold!! I better check to see if it's cold or not...what the...the temp just shot up another 5 degrees! All I did is open the door for a minute and let out all the cold air and let in a bunch of hot air.

If your compressor and fans are on then your computer thinks it's too warm in the unit and is calling for cooling. If your compressor and fans are off then your computer thinks everything is nice and cool (or it is in defrost.)

Offline KeepItSimpleStupid

  • VIP Member
  • Member Since: Oct 2016
  • Posts: 11
  • Country: us
    • Buy me a beer through paypal
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #6 on: October 15, 2016, 04:48:36 AM »
The fast Track sheet:  http://www.pcrichard.com/images/promos/RSG257AA%20Fast%20track%20R2.pdf

Could it think the freezer door is open all of the time?  Did you check that switch?


Offline danube

  • VIP Member
  • Member Since: Oct 2016
  • Posts: 9
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #7 on: October 15, 2016, 07:11:58 AM »
Good morning, and thanks for the replies.

  I think I am well beyond the basics at this point.  The freezer is working - but for how long?

  It's not easy to check the frost pattern in the freezer as the fan is attached to the cover.  I could open it up and get a glimpse.  what should the pattern look like?

  It's not the door switches nor a bad sensor.  I've checked all that.  The door open would stop the fans, and I hear them running.  The status indicator LEDs also show me the fans are running and at what speed.

  I understand what you are saying about the temperature display.  During a defrost cycle, I watched the (actual, thermocoiuple) temperature rise to 65 degrees last night.  Of course the display can't show that or the customers would freak.  But the problem I had is that after running ALL NIGHT, the display temp was -14 and in reality the whole freezer was at about 32.  After a power cycle, the thing seems to be reset.

   I left it running overnight with the 3-way valve somewhere in the middle.  the freezer is now at -8.3 (set point -14) and it even made ice.  The fridge is warming up a bit (44) so I need a better position of the 3-way or figure out if it's working.   I read in the GE manuals that you put your finger on it when you plug the fridge in and feel if it buzzes to the home position when the power first comes on.

Dan

Offline baldwinappliance

  • Technician
  • Member Since: Feb 2014
  • Posts: 198
  • Country: us
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #8 on: October 15, 2016, 09:18:29 AM »
-8.3 temp seems to me your sealed system is ok. My benchmark is if it is below +10 and I start looking at other things. Sounds like the valve is ok if you were able to manually override it...i.e. The mechanical part of the valve is good. Perhaps the control telling the valve is bad. Check the freezer fan by closing the door switch but a Samsung should have an error code for that if that is bad. It has an rpm signal for the fan. If it was mine I would replace the main board. It seems like you have tested all the components and they seem to be sending the correct signals. So the brains are receiving the correct inputs but for whatever reason it is not giving the correct outputs. $120 for a board is cheaper than all the man hours you are spending.

Offline KeepItSimpleStupid

  • VIP Member
  • Member Since: Oct 2016
  • Posts: 11
  • Country: us
    • Buy me a beer through paypal
Re: Freezer in Samsung RSG257AARS side-by-side wont freeze
« Reply #9 on: October 15, 2016, 01:12:24 PM »
You can try something that would do no harm, but sometimes can work. 

I've fixed calculators, bicycle computers, car clocks, an HVAC thermostat and computer mice using this technique. The mouse took overnight to fix.  The thermostat took a week because I didn't follow the normal procedure which normally takes about a minute.

The car clock dies when the car was jumped.  The bicycle computer (not mine) died when it was dragged across the cargo carpet.  The calculator (not mine) used commas instead of periods.  The thermostat kept turning on it's backlight.  I added a bi-directional TVS diode (A transient suppressor) and there has been no failures for 2 years.  It worked for someone on the internet too.   Searching for the post may be tough.  There is scientific evidence why the procedure can work.

Unplug your freezer/refrigerator and monitor the +5 to ground voltage.  When it drops which will probably be immediate. Short those pins for basically as long as you can.  At least a minute.   Remove the short and plug the appliance back in.  I know it sounds like folklore.  There's a connector with +5 and ground on it.  You could pull that connector and use it.

If it does work, I'd recommend a TVS on the 5V supply.  I can select the proper one for you.

 

Samsung RSG257AARS side by side refrigerator/freezer not cooling.

Started by sammy123

Replies: 13
Views: 5988
Last post March 26, 2015, 08:03:54 PM
by sammy123
SAMSUNG RS21HD side by side freezer temp swing range?

Started by ting

Replies: 4
Views: 3313
Last post January 26, 2012, 03:58:34 AM
by RegUS_PatOff
SAMSUNG RS21HD side by side freezer temp swing range?

Started by ting

Replies: 4
Views: 3301
Last post January 26, 2012, 09:32:34 AM
by RegUS_PatOff
Samsung RS21DCNS side by side fridge freezer

Started by ymfox

Replies: 5
Views: 6170
Last post May 18, 2012, 05:02:18 AM
by shillion
Samsung Side-by-Side Refrigerator warm, freezer not cooling- no frost

Started by appliance nut

Replies: 2
Views: 2669
Last post October 13, 2014, 12:20:28 PM
by appliance nut
Samsung RSA1WTMH side by side fridge freezer

Started by Homerprr

Replies: 0
Views: 1027
Last post March 28, 2015, 04:39:25 PM
by Homerprr