Twin Cooling just means there are separate evaporators (cooling coils) in the freezer and fresh food sections. Airflow doesn't mix between them and temperature can be maintained more consistently in each section. Typically there's still just one compressor and condenser (to dissipate the heat) at the bottom/back of the unit. A 3-way valve directs refrigerant (Freon) flow to the two cooling coils (freezer, fresh food, or both) as needed.There are other brands that have this system. My 2004 GE Arctica SxS has it. I've not had any trouble with those parts.

Upscale brands such as SubZero may have separate compressors for the freezer and fresh food sections so the systems are truly 100% separate operations.

Without "twin cooling" there's one cooling coil in the freezer
section and ducts to direct some of the cold air from the freezer
section into the fresh food section.

>>>"Or, is there another solution to this Samsung problem? If the extended-warranty-repairs weren't an issue, I'd keep this fridge. Is there a solution to the problem that we have not tried?"<<<

I'm wondering how much time the service guys take to "thaw it out, service it, and go on their way." That sounds like only a few hours defrosting.

If that was the case, then the little experience I have (two Samsung fridges of friends) suggests that your fridge may need a much longer defrost time.

I found that freeze ups in the two Samsung fridge created an awful lot of ice behind the inside back wall of the fridge compartment. Back there, it is very hard to see. There seems to be enough insulation in the Samsungs that It won't melt in a short defrost. If you don't get all of that ice melted and drained, then the freeze-ups come back in a month or two as you have been experiencing. I found that a full defrost took a good 36 to 48 hours of defrosting with a floor fan blowing into all compartments. (There may be ways to speed that up, and maybe somebody who knows more can suggest them.)

Also, do you know if the techs checked the condensate drain lines and collectors for gunk or pet hair or dust that might be plugging or restricting the draining of condensate? Restricted flow can be a possible (but not the only possible) cause of freeze-ups.

I'm very sure that it is not a pet hair issue....no pets have been in this house since we've lived here (26 years). Gunk? In 3 years? Probably not, though certainly that could be.

The last techs that were out here, said that this is an inherent problem with the Samsung fridges of this vintage (2015) of this design, because the doors do not close properly enough to create a good seal every time. That's why they re-leveled it in the way that they did, and the doors then closed a lot better. (Before, you could see that one door was higher than the other.)

So perhaps my question should be .... what brand in a side-by-side would be a good purchase? After spending $3200 on this fridge, 3 years ago, I certainly don't want to spend that again and get another piece of junk. We looked at some Whirlpools and Frigidaires at Lowes this morning, just to price them. They were sitting at under $1500.

Donna

To Debbi -- thanks. Samsung is not very receptive, saying that we should take it up with Home Depot. Why?! It wasn't Home Depot's fault that the fridge is a piece of junk. We may try that approach again, but one thing I do NOT want is another Samsung product. Now, to be sure, both my daughter and my brother have Samsung washer/dryers and swear by them. But I read another review online about refrigerators, and one said, "stay away from any company that makes both cellular phones and large appliances." Wish I'd have known that advice three years ago!

I bought an LG FD last year after reading a lot of reviews. There are complaints about all brands but Samsung seems to pretty consistently get bashed on appliances including not standing behind their brand when they frequently don't work.

My philosophy on reliability these days is to get as simple of an appliance as you can that meets your needs - fewer things to go wrong. My first thought with all those doors and convertible compartments in fridges was that there's much more complexity there to go wrong. Plus more expensive to build and more need to cheap out elsewhere in the manufacturing process.

My fridge is a very nice 36", full depth with no door dispenser - just ice maker in the drawer. I was a long time SxS owner and rather liked the SxS design. I do like the FD design though I don't like having to dig through the freezer drawer to find things vs. seeing it all at a glance with a SxS.

Too early to say about reliability of the LG but so far so good. The only problems I had originally (rattling of everything inside the fridge) had to do with improper installation by the local delivery people. The fridge wasn't level and when they replaced the door they scratched they also did that wrong. I had an extended warranty through the local appliance store (who had the incompetent employees) but it was LG that got involved and required that a knowledgeable, authorized service person come out and that person fixed the problems caused by the incompetents.

I just want to chip in and say I have no solution, but exactly the same problem (in fact, I'm about to start a remodel AND I am hosting book club tonight yet what am I doing...sitting here trying to defrost my Samsung fridge so the fan unthaws and starts cooling again). We had a repairman out for the fourth time in the three or four years of owning this fridge; we had him defrost it but didn't pay the $600 for the extensive part replacement he said we need, as we are about to buy new appliances for the kitchen remodel. I was hoping to limp along with this one until the remodel is done, but we'll see. He said he'd fixed the same problem in a Samsung fridge earlier that morning...and when I asked him what brand he'd buy, he said "none of them" and said he uses a medical refrigerator with a separate freezer in his own home :/.

At the appliance store yesterday, they recommended Whirlpool and Kitchenaid. I know they aren't particularly highly rated by Consumer Reports-I'm feeling stuck too..I'll be following this thread.

The extended warranty I have on my fridge (not a Samsung but equally problematic) discusses how many repairs for the same problem before they'll replace the fridge or buy out the extended warranty - does your extended warranty paperwork have this?

Our appliance store recommends Whirlpool made Refrigerators (Kitchenaid etc) also. Still not happy with reviews on these either. I will also be following this thread and appreciate all new feedback.

I have a 10 year old Ge profile that was manufactured by Samsung. Same issue with ice forming in the back. It started one year after I got it. Every so often I unplug it and let it thaw for a few days. We also did a hack we saw on YouTube with a copper wire to keep the condensation duct from freezing over. Seems like they still haven't fixed the issues. Ridiculous!!!! I'd love to get on that class action lawsuits.