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FIXED Subzero 632/F not harvesting fully


Premium Member
Feb 8, 2023
Summerville SC
Model Number
More than 10 years
Ice maker was not working. Was able to manually fill the mold and ice harvested. Assumed problem in water line. Discovered water line had become detached from back of unit - reattached. Water still not entering. Defrosted freezer, replaced water valve behind kick plate. Now water fills mold but when it harvests, the cubes just sit on top of the ice maker instead of falling into the bin. When I manually move them to the bin, after a few minutes there seem to be tiny ice cube shaped bits (not randomly shaped blockages) stuck to the prongs. Once I clear those, the cycle continues fine - until time to harvest again. What am I missing?!?!?
The reason the line became detached was the inlet was frozen and the pressure dislodged it. (bad valve which you replaced)Quite common and a PIA to have to pull out the unit. If the cubes are just resting on top the IM is stalling and not completing the cycle. I would remove fill tube to make sure it's clear.
First, thanks for your response. When performing the repairs above, I fully defrosted the freezer (so no ice blockage in fill tube) and ran a 12" bottle brush in the fill tube while it was still attached. Would you expect to find blockage beyond that? I've not removed the fill tube before and just don't want to get in over my pay grade here.

There does seem to be water filling the mold but I'm wondering if there isn't some timing issue between the holding switch/ shut off switch/ water solenoid. The water fills the mold, ice harvests but sits on top of the maker (pic 1). Then just enough water fills the mold and freezes to produce the tiny cube shards (pic 2). I'm not sure how long the water is present to make the shards, but I do know that once I clear the ice from the top, it takes no more than 5 mins (possible less) to harvest the shards. Once the shards are clear (though sometimes it takes two rounds of clearing them), the water fills the mold completely again and we start over.


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You're gonna have to give me a few days, just finished cataract durgery and near vision is zero
Sorry - didn't see this reply and didn't want to bother you post-surgery!

No I don't believe it is. The technician was out maybe two years ago. I know there were several different attempts of repairs but ultimately I believe he swapped it.

As an update from my last post, we started seeing a large frost buildup in the area behind the ice maker along with a louder, higher pitched hum. Immediately shut down the freezer section and defrosted. Once defrosted and restarted, the ice maker would not harvest at all. Ordered replacement ice maker. Removed old ice maker, then realized new ice maker didn't have wiring harness and was not easily compatible with existing harness. Reinstalled old ice maker.

Lo and behold - old ice maker produced a batch of ice overnight (still sitting on top of maker as before). Cleared ice (and batch of shards a few minutes later), now mold is full of water but not harvesting and starting to see frost build up again.
I noticed that frost in your first pic. It seems to me the ice maker is only making one revolution, it should make two. It's stopping at the home postion after one revolution and cubes will sit there until 2nd revolution (I love that word) tosses them into the bucket. If the temp is above 15 it will only make one revolution, could be the frost build up on evap. The shards I don't get? Depending on where you got the new ice maker it should have come with an adaptor harness.
The panel shows that the freezer unit is at zero degrees (and pretty much has been with slight variations since the defrost). I'm not sure I follow - are you relating the frost build up on evap to it making only one revolution?

Because it is an older unit, I was more focused on it matching the part number from the parts diagram and overlooked that it said no wiring harness in the description - my error.

Is it possible there is some fill or timing issue that might cause the shards? It almost looks like a small amount of fill happens sometime in the duration of the cubes resting on top of the machine. Once the cubes are cleared manually, it then harvests what it thinks are cubes but are actually shards??
What's your ser #? I would shut off IM @ display but make sure there's water or ice in the mold first. Next day remove 2 screws in assy above IM and prop up so you can see the IM run. Turn IM back on and watch what happens. It should fill on 2nd revolution.
Serial number P1952511.

I will try this tomorrow. To clarify, you mean the screws that secure the shelf bit above the IM, not the screws attaching the IM correct? Also if I am supposed to make sure there’s water in the mold, if it fills on the second revolution will it overfill? And it will still make ice with the door open?
Yes the shelf. Water should be frozen by then. Yes the door can stay open but ice bucket in and pushed back.
Tried your suggestion and the tines only came up to horizontal leaving the ice sitting on top as it had before. No second revolution to refill, no shards.
So IM is only making 1 rev. leaving cubes sitting on top. What little water is left in mold freezes, IM cycles(really rev #2) dumps those cubes and pushes out the shards from water left in mold.

part # of IM? Based on your ser# you should be able to go into log recall diagnostics. I'd be curious to see temps. Once in temp recall the readings are in two hour increments for 14 days of readings. Go into diag, press any colder key then unit on/off and release both. toggle by pressing colder til you see temp# on left and F on right. Then press frz warmer and then unit on/off and release both. Temp on left and 01 lright. Toggle thru by pushing frz warmer key. Note each reading.
After 20 sec's of no toggle it cancels. You can go back into diag but this time toggle til FE shows then frz warm + on/off and now you're see evap temps.
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Thanks for your patience! Temps are as follows (temp/ reading number(s)):

Freezer: -02/ 1-14; 00/15; 14/ 20-21; 00/ 22; 28/ 34; 18/ 35; 10/ 36; 44/ 37; 68/ 38; 66/ 43; 64/ 44; 60/ 45; 26/ 46; -02/ 47; 04/ 48; 00/49-51; -02/ 52-56; 00/ 57; 16/ 58; 08/ 59; -02/ 60-71; 14/ 72; -02/ 73-88; 12/ 89; -02/ 90-100

Freezer Evaporator: -8/ 1-19; 24/ 20; -8/ 21-32; -10/ 33; 26/ 34; 00/ 35; -02/ 36; 38/ 37-41; 68/ 42; 66/ 43; 64/ 44; 52/ 45; 06/ 46; -24/ 47; -16/ 48; -12/ 49; -14/ 50; -10/ 51; 00/ 58; -02/ 59; -08/ 60-68; -06/ 69; 24/ 72; -04/ 73; -08/ 74-86; -06/ 87; 24/ 89; -08/ 90-100

Wasn't sure how many readings you needed. Obviously it shows where I defrosted the freezer. After I defrosted, I ran the IM to perform the visual you suggested but turned it off after that.
Here we go, much easier being there. You can see the defrost cycle @ evap #'s 20,34,72,89. Looks like you shut it down @ evap 37 til 46, around 22 hours. Notice evap 20&21, +24 & -8 vs frz temps of +14 for 4 hours. Also evap34,35,36, +26,00,-2 vs frz temps of 28,18,10, 6 hours. Then you shut it down. After you turned it back on (46?) evap @ -24,-16,-12,-14,-10 then 00 @ 58 with +16 in frz. It seems to me evap fan is not running at times. +14 for 4 hours is too long and those evap temps after you turned it back on start out very low which would occur without the fan running.
The fan is behind the evap, the IM in front so the air flow is directly related to IM. The compartment thermistor is right in front of the IM on the wall. You did the IM cycle once and it only made one revolution, you need two. Try it again after an overnite. Before you turn it back on go into diagnostics and check evap & frz temps. If frz temp below 10 it should make two revolutions. You never said what the part # was of the IM you put in.
I didn't actually put in the ice maker - the one I ordered didn't have the wiring harness and was incompatible to swap the old harness to it. 4200521 was the part number I was using to locate it though I never looked at the old one - rather the parts diagram.

If the IM has been turned off for several days, is that the equivalent of an "overnight" (can I check the temps and try it now?) Do I need to manually fill the mold as before or try to let it cycle on its own?
There needs to be ice in it before you cycle it. If not you can add water(3.5 oz if mold is empty) then wait overnite. So the original IM is in the unit?
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