Manitwoc Ice Mach. Contactor flutters

[Bobgrif]

I have a Manitwoc Ice Mach. Mod. SY0455W that runs through 1 complete cycle fine, then half way through the second cycle the contactor begins to "flutter" causing compressor to stop on overload protector. I have replaced the contactor (contacts burnt) and the bin switch. but it keeps doing the same thing. It is water cooled. No problem with water, refrigerant levels are OK. What next?
Bob

[mikeref]

Hi Bob, maybe power supply not up to scratch or control circuit transformer failing?

[install monkey]

loose connection on a screw terminal-is the socket ok

[Bobgrif]

What screw terminal?

[Bobgrif]

When the contactor begins to flutter, all the lights on the circuit board are flashing as well. . .

[Magoo]

The processor board is having a fit as it heats up, new PCB required.

[acura]

had a similar prob replaced shorted contactor replaced that and then found water pump was the problem , replaced pump then circuit board relays erratic and cooked new water pump , Hate ice machines . Wish the customer listened to me from the start and replaced machine

[charlie patt]

ah the old age problem of trying to advise a customer i have had problems with the boards but mainly due to pressure switch faults or pressure problems

[FEISTY]

I agree with Magoo. Work 95% of the time on Manitowocs and would take them over Hozi or Scotsman any day. You didn't include the date code of unit so I can't identify model of board but definitely sounds like voltage variation thru bad processor. You can give tech support a call. Again best group of guys to ask when you are stumped. 1-800-545-5720. Just be on site when you call as they will ask for hands-on info, such as reading between this and that, temp and/or timing, etc. I've started a " spare part box " from condemned units I pull. Sometimes better to take 15mins. and swap out a part to check your guess before buying a 350.00 board & have same thing happen. Good luck.

[Bobgrif]

I appreciate your help and experience! Thanks, Bob

[Magoo]

Hello Bobgrif.
You could always pull the PCB out and clean all plug ins and remote connects, use a contact clean spray can to clear any problems. The card is in a non freindly enviroment so corossion will always be a problem.

[texas64]

Check the ground to the unit.