Scotsman SCE170 making me nuts

[kevink1955]

I have a Scotsman SCE170 under counter ice maker that is driving me crazy.

It makes a perfect evaporator plate of ice in 21 to 23 Minutes (within spec) goes into harvest where it should drop in about 2 minutes. It does not drop, the ice will hang onto the evaporator for the entire harvest (7min) by then most of it will be melted. Then the unit comes out of harvest what is left of the ice is so small it falls into the water trough.

Both the water drain (purge) valve and hot gas solinoid operate, you can hear the ice crack soon after the unit goes into harvest. It just will not let go of the ice, if I try to pull the ice off the evaporator at 4 to 5 min into the harvest it is still stuck and will not come off as 1 sheet.

I am thinking the plating on the evaporator is shot and that's why the ice is sticking. Anyone have any ideas, anything I have missed???

[Dowadudda]

yep

[wannafreeze]

I had an ice-o-matic that I got it going by pulling out the bottom horizantal bar of the bottom grid.the only thing is though the bottom cubes are double size.I don't change evaporators,just tell the customer to buy a new machine..
I will be checking a cornellius on monday just to condemn it too.two months ago replaced the txv.bottom grid is rusty.it stuck once one week after the repair.maybe I will sand it down to see if it will buy them some time.

[itsiceman]

If you can't pull the ice off at 4 or 5 min. your not heating up the plate. It is probably dirty too

[kevink1955]

The low side pressure does go up during harvest so I assume the hot gas solinoid is opening, the evaporator does make full cubes so I do not think it's undercharged. What else could cause the ice to stick.

[itsiceman]

Inefficient compressor, cond. fan not turning off, water purge valve not opening, flooding txv, cold ambient, hot gas valve not opening enough

[DoctorIce]

Make very sure the machine is level side to side and perhaps leaning forward a bit. Also the curtain has a tendency to not seat all the way down which causes weird problems.

[kevink1955]

Out of all the things listed the only thing I can aggree with would be "hot gas valve not opening enough"

I think I can rule out compressor ineficent and all other refrigeration problems as it makes a full evaporator of ice within the specified time. The condensor fan does shut down on harvest and the purge valve does dump.

The ice is just stuck, I have never seen a solinoid that did not open all the way but guess it could happen.

Anyone think it could be worn plating on the evaporator, I have 3 of these things and looked at the 2 that are working ok. I could not see any differance between evaporator condition but who knows. The 3 machines are in 3 diffrent buildings, the one that is giving me problems is on a diffrent water company than the other 2, makes me wonder about water conditions.

[itsiceman]

If you have access to the machines and a thermometer compare temps at the same points in the cycle like compressor discharge temp just before harvest on both machines.

[tbk]

Check the grip plates for loose, they are not supposed to move at all!
common failure and same problems on many of these 170's.
Oh and the new plate only cost $600.00 lol

[push 2 reset]

ice is more than likely forming in bettween the plastic grids that make up the evaporator causing it to do what you describe and this advice is only good if you did all the other checks that were told here. Just a question, why bother with this at all labor cost alone dictate that this machine should be scrapped it is not a problem that warrant futher trouble shooting the end result will be a high repair invoice so do yourself a favor and save a lot of greif, the customer will be much happier in the end rather thn trying a fix on an old machine

[kevink1955]

I aggree that it's not worth the time but they pay me to be here all day anyway. If it comes down to the Evaporator being bad then the machine will be replaced. I just want to be sure I am not missing something.

I am going to shoot temps and look at low side presure on one of the identical units before I give up on this one.

Been working on ice makers since KoldDraft had Float Chambers, always hated wating around for 1 or more cycles to see if it's fixed.

[idontgetit]

Dirty plate, ice forming other than on plate and bridging, grid seperation in that order if we are to assume that the harvest pressure is high enough.

Make sure the bridge is thick enough, I have seen the ice hang up when it was not heavy enough to pull loose of the vacuum pulled when it tries to seperate.