Troubleshooting Safety Limit #1 On Koolaire Ice Machine July 08 2015, 5 Comments

Koolaire, like other Manitowoc made ice machines, come with a built in safety limit feature on the control board.  This is a feature that shuts the ice machine down, if certain limits are reached, to protect the ice maker and its individual components. If the machine were not to shut down with these limits, you could potentially damage your compressor, evaporator, or electronic board. Although frustrating when the ice maker goes down, these safety limits protect your investment. This article will discuss the checklist and things you should check if your Koolaire were to shut down on Safety Limit 1.

What Does Safety Limit #1 Mean

Safety Limit #1 is activated whenever the ice machines freeze time exceeds 60 minutes for 3 consecutive cycles. If your ice machine has not made ice with 60 minutes, it's not going to. The typical freeze time should be 12-15 minutes max. Anything taking longer indicates there is a problem, or your ice machine needs to be cleaned. Either way, a shutdown is warranted after 3 cycles in a row.

Causes For Safety Limit #1

Improper installation can affect the freeze times on a Koolaire. This means, make sure you followed the installation use and care manual, while installing your new ice machine. If it cannot breathe properly, have proper sized water lines, or proper power supply, it could cause the machine to shut down on Safety 1.

Water System

It's possible your float switch is not activating properly or you are losing water out of your water trough. Check to ensure proper installation and no cracks in the plastic trough. Also, low water pressure, under 20 psi, or high water pressure, over 80 psi could affect the freeze cycle. If you are unsure, install a regulator and gauge on the water line coming to your ice maker.

Dirty and clogged distribution tubes could be limiting the amount of water flowing over your evaporator. Check for debris and clean if necessary, it takes water to make ice. Which also leads us into the water inlet valve and water pump. Ensure you are bringing water into the trough and the pump is pushing it up and over the evaporator. With low or no water, the machine will not freeze a batch of ice and shut down.

Electrical System

The freeze cycle is terminated by the harvest switch, if it's not functioning properly the control board will not know to stop freezing and go into harvest mode. Even though you may have a great batch of ice, it'll keep freezing because the probe is not telling it to switch modes. Check the list of other ice machine parts below, if one were to fail it could cause a long freeze, shutting the Koolaire off on long freeze cycle.

  • contactor
  • condenser
  • fan cycling control
  • fan motor

Before replacing any of the above components, make sure that the Koolaire has been cleaned thoroughly. This means both the food zone, where the ice forms and the air condenser on the outside, for Air-Cooled and Traditional Remote models.

If you have any specific questions about a Koolaire safety limit or need help troubleshooting, feel free to contact Ice Maker Parts Shop at

Refrigeration System

Refrigeration components could also be the culprit when diagnosing or troubleshooting a Koolaire ice machine on safety limit #1. We do not recommend untrained professionals working on the refrigeration side of commercial equipment, but below are the items that can be checked.

  • non-OEM components
  • improper refrigerant charge
  • defective compressor
  • TXV starving or flooding
  • non-condensible in refrigeration system
  • plugged or restricted high side refrigerant lines or components
  • defective harvest valve

Ice Maker Parts Shop recommends trained technicians diagnose and troubleshoot the refrigeration system on any commercial ice machine.