12 replies to this topic

[mehoss]

I hope this post helps someone out there! Had a difficult repair this week, customer complained about no ice. Water was not getting into the icemaker.

Shorted V-L to manually activate the water valve. This checks several things: water supply/water valve/frozen inlet. Water flowed into IM.
So I replace the entire Ice Maker, no joy.
Turns out that when you short V-L, you are sending 120 volts to the water valve, BUT the ice maker sends the voltage in SERIES with the Mold Heater (72 ohms). So you are getting using ohms law (assuming the water valve is ~175 ohms) about 85-90 Volts to the water valve. It turned out that this valve refused to operate at the normal voltage below 120, but when full 120v "test" voltage was applied, it opened up just nicely.
Replaced the valve, all is well. By the way, I tried replacing just the valve coil to no avail, it turns out that the sticking mechanical guts of the valve were requiring the extra voltage to get them to move.
Thought I would share this. Now I need a test rig that contains a 72 ohm resistance to properly test the water valve in the future.
Also on the subzero 532, you can replace the valve without having to jack up the unit. Remove the ONE screw that you can easily see and get to where the water enters the valve. This will allow the valve to slide out of the bracket to be replaced. No need to remove any other screws, especially since you cant see them or remove them easily.

Edited by mehoss, 15 September 2012 - 08:28 AM.

[RegUS_PatOff]

... So you are getting using ohms law (assuming the water valve is ~175 ohms) about 85-90 Volts to the water valve.
... Now I need a test rig that contains a 72 ohm resistance to properly test the water valve in the future.

1) Ohm's law ... maybe , but the Water Valve may be 175 Ohms resistance, not AC inductance (long story)
On some tech sheets, it mentions the Dispenser Valve is 20w and the IceMaker Valve is 35w (= 411 Ohms inductance)
A 75 OHM 10w resistor should work when inserted into V - L
should read about 20v AC across it (may get hot, about 5w of heat)

[mehoss]

I ordered a 10 Watt Cement 75 ohm Resistor. I do fully expect it to get hot...I only need a few seconds though. I need to fabricate a set of test leads that is able to fit into the test holes even when the IM is mounted to the side. I use my meter set to amps to short the test points, but have to remove the ones mounted sideways. Thinking to get some thin 1 inch long machine screws with ring terminals between 2 nuts to hold the test leads, then insulating them.
Mold Heater - 185 Watts, 72 ohms interesting... wondering if I have a big enough resistor, perhaps I should just use an old mold heater instead.

-henry

Edited by mehoss, 15 September 2012 - 01:32 PM.

[RegUS_PatOff]

actually, the Mold Heater is about 175w, because when needed it gets 120v (not your resistor)

[mehoss]

Ah, yes that's right! It gets the entire 120 volts when the thermostat is closed!!! OK, I'm safe with 10 watts.
Thanks Reg.

[RegUS_PatOff]

resistor (or jumper L-V) should only be used when the IceMaker is in the "home" position,
otherwise the IceMaker could possibly connect V to Neutral (I'm not sure)
(burn out resistor OR Icemaker if L-V jumpered)

[BNS]

so I have a somewhat similar problem with a SZ 650 that is about 12 years old. Only produces very little ice, pulled drawer and check IM, it is the 1m model, two gears on front one big one small, held three switches and advanced cycle with gear, no help, check water line at valve at kick plate, no filter, water flow ok, replaced water valve after some strange ohm readings at valve, no help, still makes very little ice. Any ideas next?
Thanks

[Scottthewolf]

so I have a somewhat similar problem with a SZ 650 that is about 12 years old. Only produces very little ice, pulled drawer and check IM, it is the 1m model, two gears on front one big one small, held three switches and advanced cycle with gear, no help, check water line at valve at kick plate, no filter, water flow ok, replaced water valve after some strange ohm readings at valve, no help, still makes very little ice. Any ideas next?
Thanks

That's a Midsouth icemaker. You probably have a clogged saddle valve because the installer used a self piercing water valve rather than one you drill the hole in the pipe. The self piercing saddle valves are bad news because the hole is so small, a single piece of sediment can block the flow of water.

[RegUS_PatOff]

... produces very little ice,

1) small Cubes ?
2) only a few Cubes per batch ?
3) full size Cubes, full size batch, not many batches ?

[BNS]

Interesting idea about the problem at the saddle valve. When I open the water line at the inlet to the water valve at the kickplate I get what seems like plenty of flow. The ice I do get would seem to me to be normal size, and normal amount but not enough cycles, good question. So what controls the number of cycles?

[RegUS_PatOff]

... normal amount but not enough cycles, good question.
So what controls the number of cycles?

Freezer temperature ... usually about 0F .. the colder, the faster
IceMaker won't "harvest" the Cubes unless the Freezer is +15 or colder
If Freezer temperature won't go low enough,
may have a common SubZero leaky Evaporator..
may need to see a picture of the Evaporator Coil frost pattern inside the Freezer

[BNS]

That does not sound like a fun one. The 'set' temp is 4. I will check when I get home. We did have a leak years ago in the fridge side that had to be repaired, not cheap. Where is the Evaporator Coil located for the freezer? Somewhere behind the plastic back panel I assume

thanks

[RegUS_PatOff]

... Where is the Evaporator Coil located for the freezer? Somewhere behind the plastic back panel I assume

OR first, check the Freezer temperature