20 Most Recent Hoshizaki Freezer Commercial Ice Machines - KM900MRH Commercial Ice Machine - Page 6 Questions & Answers

This calls for a tech that is familiar with this stuff. I have one a work and it runs great but I can't fix me. There several things it could be. Is it waking water anywhere. And does it run constantly.

Well aside from jacking the machine up and putting another in its place, the only thing left is the electronic thermometer/thermostat that should be sensing the ice and not the outside temperature. By the way, if you spend more than the machine is worth think about another one.

You will need to replace the "defrost thermostat" on the unit. Here is the kit to order.

Is the compressor overheating when this happens? Feel the top of the compressor when this is happening and tell me if the top of the compressor becomes extremely hot to the point that you cannot keep your hand on the compressor. Reason I ask you to do this is that it is possible that the compressor is short cycling because of a defective start relay and/or run capacitor. Let me know if the compressor is overheating of simply turning itself off. I will post a service manual if interested but would like to e-mail you the service manual for your Hoshizaki KM-255BAH because of copyright issues. You may contact me HERE if you like. Thanks Sea Breeze

check for a stuck float switch. located near the water pump. Usually white plastic with a tube on top and a black boot at the bottom. Tap on it lightly while unit is filling with water. If that works, you need to disasseble and clean.

the bin stat is either out of place or is not adjusted correctly. The machine should stop in no more than 10 seconds after the sensing bulb is submerged in ice. Make sure the bulb is mounted correctly and they come out of their holders on a regular basis.

The board is telling you that there is an issue. Usually there is a series of beeps indicating the issue. the reset button is on the board, near the top of the board and is small and white. press it to reset.

If you are asking about the valve to the left of the water pump, it is used to dump water when the unit pumps the water out of the sump to keep sediment out. If it is bad, the unit will have short freeze cycles as the the valve is leaking water out causing the float to drop prematurely and causing small cubes and short freeze cycles.

If your are asking where it is located, it is on the control board, in the electrical box. White button near the top of the board.

Look for a stuck float switch. unit fills with water for 1 minute, then the board "looks" at the float to "see" if there is enough water in the unit to run. If float switch is stuck down, it tells the unit there is not enough water and the unit stays in the fill cycle causing the sump to overflow and send water down the drain constantly. Compressor will not run till the board senses that there is enough water to run.

If you did a cleaning cycle and used the bypass valve to clean between the evap plates, look for the micro switch on the bypass valve to be bad. It is a small switch attached to the by pass and keeps the compressor off during the cleaning process. I'd start there.

cycle is, fill cycle for 1 minute first. If there is not water entering the unit when first turned on, look for that issue. Water turned off, water valve not working or some restriction, clogged water filters, etc. That is got to happen first. Don't over look the bin stat being bad. Nothing happens if teh bin stat is bad. It sends voltage to the control board that runs the unit.

If you are asking about the LED's that are on the control board, the board is inside the electrical control box.

float switch is stuck in the "down" position. The unit goes thru a fill cycle and after 1 minute, the board "Looks" at the float swith to "see" if the sump is full. If float is stuck down, it tells the board that the unit does not have enough water and stays in the fill cycle. The compressor will not come on as long as the machine "thinks" there is not enough water. let me know if I can help further

that could be one solution. I would look at how long the freeze cycle is lasting. The machine could be cycling off and on via bin stat. Average cycles from start of freeze cycle to start of freeze cycle is usually around 25 minutes or so. If it is taking longer than that, you may have to dig deeper. let me know. Don't overlook a leaking water valve.

It should have a regulating valve to help control the head pressure. It is adjustable to maintain a constant head pressure. The higher the pressure, the more the water should flow to keep the pressure down. Since there is not model number, I can not suggest an exact setting.

I am not sure about the commercial ice, but I would check to make sure the water tube that goes into the maker does not have an air bubble in it. That can cause the water not to come into the freezer to make the ice cubes.

There is an adjustable potentiometer in the pcb section. Adjust it to give a thicker cube. Also check water pump and clean any scale buildup from the sprayplate. If all else ok and still no ice suspect evaporator sensor.

CORNELIUS AC-500-SS-MH COMPRESSOR. Cornelius tech dept informed me that the compressor for this model is obselete and they did not have a replacement to recomend. Also the tehnical dept could not even find any listings for this model. It is a old version of icemaker that uses R22. The compressor as best I can find is a 3/4 hp, 6250 btu unit that supports a 20 degree evaporator temperature. I have done a lot of web searching and cannot find a suitable replacement in any brand.

There is a thermostat probe sat on the front of the evaporator to tell the control board when to harvest. Check it is tight in it's holder. Check the condenser is absolutely clean and filters clear. You can adjust the thickness of the cube. set it on the thinnest setting and see if it harvests before freezing solid.