How To Clean A Manitowoc Ice Machine January 09 2014, 3 Comments

This article will cover the steps required to properly clean the inside of a Manitowoc ice maker.  Please note that depending on the size of the machine and which series, you may have some slight differences.  The most common difference may be the amount of cleaner required or the frequency of cleaning.

It is recommended that you clean and sanitize your ice machine at least every 6 months, however must be done on an as needed basis.  There are companies that can perform a water analysis to decide how often a cleaning may be necessary or even recommend a water filter system.  If you are having problems with slime, typically with machines located near bread baking areas, I'd recommend a K-00206 Guardian Sachet.

Step 1

First turn your ice machine toggle switch to the OFF position, after the last batch of ice falls from the evaporator.  Alternatively you may turn the ice maker switch to OFF and wait for the ice to melt off of the evaporator.

Step 2

To allow for easier access to the components of the ice maker, remove the top cover.  This will also allow you to more easily add the cleaning and sanitizing solutions.

Step 3

Remove all ice from the bin.  Depending on the cleaning and sanitizing solution you use, this may not be necessary, but is recommended.  Please consult the warning labels on the cleaning and sanitizing chemical you are using.

Step 4

Move the toggle switch to the CLEAN position.  At this point the ice maker will turn on, energizing the water dump valve.  Once emptied, the water trough will then refill with fresh water, wait until water begins to flow over the evaporator, then add the right amount of ice machine cleaner to the trough.

Tip! Generally you can expect to add just 3 ounces of cleaner for 300-400lb cubers, 5 ounces for machines producing up to 1200 lbs, and 9 ounces on machines making between 1400 and 1800 lb of ice in a 24 hour period.  Again, please consult your specific ice machine and cleaning product being used.  In addition, ensure that if you are cleaning a Manitowoc cuber that you use NICKEL SAFEchemical.

Step 5

Wait until the clean cycle complete, which can take up to 30 minutes.  Once hte clean cycle is complete, move the toggle switch to the OFF position and disconnect power to the ice machine.

Step 6

Remove the following parts for a more thorough cleaning.

• Water Curtain, by slightly flexing the center and pulling each individual tab out.
• Ice Thickness Probe, by pinching the hinges on the top of the sensor.
• Distribution tube, by removing the thumbscrews at the top of the evaporator and pulling it away from the sealing o-rings.
• Water Trough, by depressing tabs closest to the outside of the machine. (On applicable machines only, some troughs cannot be removed.)
• Water Level Probe, by pulling straight down from the bottom of the machine and then detaching the pig-tail of wires.
• Water Pump, by pulling the pump straight down, then unplugging from the wire harness. *Warning, do not soak the water pump motor in the cleaning or sanitizing chemical.
• Evaporator Tray, by loosening the thumbscrew on the far left bottom of the evaporator and sliding the tray left. (On applicable ice makers only, some machines are not equipped with evaporator trays.)

Step 7

Create a solution of cleaner chemical and warm water.  Depending on how bad the scale build up is, depends on the solution you will mix, usually it is recommended to add 16 oz of cleaner chemical to 1 gal of water.

Step 8

Use 1/2 of the solution you created to clean all components.  The solution will foam when it comes into conctact with scale build up, once the foaming stops use a nylon brush to clean the parts.  Do not use any brush that would be too abrasive, it is important that you do not scratch the components.  Allow parts to soak for at least 5 minutes.  When finished, rinse all parts with clean water.

Step 9

While waiting for the components to soak, use the other half of the solution to clean the interior foodzones in the ice machine.  Again, use a solft nylon brush to thoroughly clean the following areas:

• side walls
• base
• evaporator plastic parts, including the trim along the sides and molding
• bin or dispenser

When you are finished scrubbing the food zone areas of the ice machine, rinse with clean water.

Step 10

Mix a solution of sanitizer and warm water.  We recommend using treating 6 gal. of water with 4 oz of sanitizer.

Step 11

Use half of the solution created to sanitize all components removed.  Use a cloth or sponge to apply the solution to all the surfaces or simply soak all components in a large enough container.  Do NOT rinse the parts after sanitizing.

Step 12

Use the remaining sanitizer solution to clean the foodzone surfaces inside the ice maker.  Use a cloth or sponge to apply to the areas listed  in Step 9.  Do NOT rinse the sanitized areas.

Step 13

Replace all ice maker parts.

Step 14

Reapply power to the ice maker and place the toggle switch to the CLEAN position.

Step 15

Wait roughly 2 minutes until the water starts to flow over the evaporator.  At this point add the sanitizer to the water trough.  We recommend adding 3 ounces of sanitizer to machines producing 300-1200 lb of ice per day and 6 ounces to ice makers producing 1400-1800 lb of ice per day.

Step 16

The ice maker will stop after completing the CLEAN cycle.  Place the machine in the OFF Position and disconnect power.

Step 17

Repeat step 6.

Step 18

Repeat step 10, by creating another sanitizer and warm water solution.

Step 19

Use half of the sanitizer solution to sanitize all removed components, repeating the sanitizing steps.

Step 20

Repeat sanitizing the inside of the ice maker by following step 12.

Step 21

Install removed ice maker parts, restore power, and move the switch to the ICE position.

If you have any questions about properly cleaning or maintaining a Manitowoc ice machine, please feel free to contact Ice Maker Parts Shop.

Before Replacing A Manitowoc Control Board January 09 2014, 77 Comments

Safety Limit #2 On Manitowoc Ice Machine January 09 2014, 133 Comments

When your Manitowoc ice machine shuts down prematurely, it most likely is going off on what’s called a safety limit.  On Q Series ice machines there are 2 different safety limits, that will help you diagnose the problem.  To check the which safety limit is the problem, simply turn your machine from the off position to ice and count how many times the harvest light flashes.  Below are what the 2 safety limits mean.

Safety Limit #1 : If the freeze time reaches 60 minutes, the control board automatically initiates a harvest cycle.  If 3 consecutive 60-minute freeze cycles occur, the ice machine stops.

Safety Limit #2 : If the harvest time reaches 3.5 minutes, the control board automatically returns the ice machine to the freeze cycle.  If three consecutive 3.5 minute harvest cycles occur, the ice machine stops.

Safety Limit #2 is a more common safety limit and can be caused by the ice maker simply being dirty.  A dirty evaporator will hold ice and not allow it to fall until it is mostly melted away.  Because there is not enough ice to force the water curtain open and break the bin switch, the machine simply thinks it never harvested.

Assuming your ice machine is clean, there are 2 other areas that are most common for shutting a Manitowoc Ice machine down on a safety limit #2.  A missing magnet on the water curtain or your water curtain being broken will cause your bin switch to fail.  The magnetic bin switch on a Manitowoc ice machine relies on proximity to the magnet to know when to terminate the harvest cycle.  This switch will not read if it does not make proper contact with the magnet.  To remedy this issue simply replace the water curtain.

Another culprit, which can also lead to intermittent problems, is a failed bin switch.  The only way to properly test a magnetic bin switch is to OHM it out and look for consistency.  However, it is possible for the switch to fail on say the 100th time, so if you are experiencing regular Safety Limit #2 lockouts, it might be a good idea to go ahead and eliminate the bin switch by replacing it.