Troubleshooting Manitowoc ice machine – produce enough ice?

5 Common Troubleshooting steps – Problems and how to troubleshoot the Manitowoc commercial ice maker

When Troubleshooting Manitowoc Ice Machine – What to check for: Most anyone can check the following consistently common problems or conditions. These 5 steps should be completed (not skipped) to avoid missing the problem.

1. .       Check the room temperature
   Any temperature above 70º can result in excessive melting in the storage bin. Since the ice machine rejects heat into this space, it needs continuously cool air to enter the condenser.

2.       Check the water temperature
As the inlet water temperature increases, the ice production rate decreases. Any temperature increasing above 70ºF degrades the standard production rate. This is expected and not considered a defect. Check the factory production chart and compare the expected vs. actual production rates.

3.       Level the ice machine
If the ice bin and machine are not leveled, the sensors intended to detect the water reservoir levels can inaccurately detect the water levels resulting in every production variation possible.

4.       Thoroughly clean the ice machine
This is often the MOST overlooked item when dealing with low or poor ice production issues. Don’t overlook thoroughly cleaning and sanitizing the ice machine, as it provides the (almost) perfect starting place when diagnosing ice production problems.

Heavily scaled ice machines require special procedures for restoration. Ice machines have frequently been neglected and water treatment lacking. Consider that the evaporator is beyond economic repair before investing time and money. Otherwise follow the Manitowoc factory cleaning instructions to obtain the correct (specified) cleaning solution and procedures.

5.       Check the water line in the reservoir
If the purge valve is seeping (commonplace), the water level in the reservoir can unexpectantly drain during the freeze cycle. Suppose the water inlet valve never allowed sufficient water into the reservoir at the START of the freeze cycle. In that case, there might not be enough to complete a normal cycle. Check the water filter to ensure there are no restrictions on water flow that can contribute to inconsistent water levels.

If, after checking, the 5 items above won’t solve the problem of low ice production, then more complex solutions are needed. Check for predefined display codes if your ice machine is built with a control board.

First, a Caution! As technology advances, so does the complexity of specific systems, including those in the commercial refrigeration and ice machines. While onboard diagnostics found in these machines can help detect issues, it is essential to note that they may not always provide a clear-cut solution to the problem at hand.

Consider that, at the end of the day, the combination of modern technology and skilled professionals ensures top-quality performance and reliability in commercial ice machines.

Does the front display (if equipped) display error codes? Many items below require a specifically trained technician. They are beyond the scope of user interaction due to the special tools, EPA Certification, and commercial ice machine installation or service manuals and training required.

E01 – Long Freeze Cycle

·         Consider deep cleaning the ice machine.

·         Check the potable water temperature. Any temperature above 50ºF increases the length of the freeze cycle

·         Check the temperature of the ambient air surrounding the condenser. Any temperature above 75ºF extends the length of the freeze cycle.

E02 – Long Harvest Cycle

·         Primarily, the evaporator requires cleaning or is damaged. Is the plating still intact? If the plating is damaged, consult a trained technician for repair. Technician? Consider replacing the evaporator as outlined in the factory service manual.

·         Secondarily, the temperature of the compressor discharge gas affects the harvest cycle timing. Suppose the refrigeration system has an efficiency problem. In that case, the temperature of this gas might be low enough to cause a longer harvest cycle.

E03 – Input Power Loss – Reset the circuit breaker or consult an electrician

E04 – High Condenser Temperature – Inspect the condenser coil and clean it as necessary. Check the temperature of the ambient air surrounding the condenser. Any temperature above 90ºF is considered excessive. Temperature above 100ºF is considered extreme and can cause E04 to display and shut down the ice machine.

E05 – High-Pressure Control Opened – the ambient temperature is excessive; the condenser airflow is blocked due to contamination, or the condenser fan motors (s) have failed.

E07 – Starving TXV Single Evaporator or Low On Charge – If the refrigeration systems have been previously opened, consider that the liquid line drier is restricted, the TXV inlet screen is restricted, or the TXV is damaged. If the refrigeration system has not been opened

E08 – TXV Fault Single or Dual Circuit Evaporators-the same indications as in E07 apply. Multiple evaporators require inspection of the check valves and both evaporator temperatures to determine the affected TXV. Follow the factory service manual troubleshooting steps.

Find Manitowoc Factory Service Manuals here

E09 – Flooding Evaporator Fault Single Evaporator, Single Circuit – See E08

E10 – Flooding Evaporator Fault Dual TXV, Dual Circuit– See E08

E11 – Refrigeration Fault Curtain Fault – the water splash curtain position is undetected. Depending on your ice machine model; inspect the ‘tab.’ If the tab is intact, inspect the curtain (position) switch per the factory service manual.

E12 – Curtain Switch Fault – Open more than 24 hours

E15 – Fan Cycle Control Fault – Low Liquid Line Temperature – ensure the condenser is not operating below 50ºF ambient temperature. Ensure the fan cycling switch is correctly cycling the condenser fan motor.

E16 – Remote Condensing Unit Fault (CVD Only) – the liquid line temperature has exceeded the allowable range of 40 to 140ºF. A low temperature indicates low ambient temperature or low refrigerant charge. An excessive range indicates the condenser fan motor circuit is not working well or at all.

E19 – Ice Thickness Probe Fault – Check that the probe is clean and void of ANY visible scaling. Clean it first using a descaling solution. Sanding is not recommended to avoid rapid rescaling. Measure the resistance of the probe with an accurate probe temperature. Record these two measurements and compare them to the factory chart. If the probe is 10% or more out of range and is without scaling, replace it.

E20 – Water System Fault – a failure or out-of-range measurement of either the high or low water probe. An excessively low evaporator temperature, possibly due to low water levels.

E21 – T1 Temperature Sensor Issue – the temperature has fallen outside the allowed parameters set by the control board. Consult the factory service manual for the correct values, and measure the sensor temperature and resistance while in operation.

E22 – T2 Temperature Sensor Issue – see E21

E23 – T3 Temperature Sensor Issue– see E21

E24 – T4 Temperature Sensor Issue– see E21

E25 – Bin Level Probe Low Sensor Fault – the low water sensor has failed, or the connection at the control board is corroded.

E26 – T6 or T7 Temperature Sensor Issue – see E21

E27 – T6 or T7 Temperature Sensor Issue – See E21

E28 – AUCS – the Automatic Cleaning System (AUCS) board is missing or not connected when that function is selected-log entry only

E29 – USB Communication Fault – defective USB drive or missing USB drive

E30 – USB Download Fault – defective USB drive or missing USB drive

E31 – Indigo Safe Mode event log – The machine operates based on historical values stored in the control board memory. This entry indicates a sensor has failed and requires diagnosis.

E32 – RS485 Communication Fault – event log entry only

E33 – Touchscreen Fault – check the connection to the control board or consider that the touchscreen has failed. Physical damage requires replacement.

E34 – Display Fault – Indigo nxt data history event log only

E36 – Check Sum Error – the control board is thoroughly confused. Restart the ice machine by powering it off with a circuit breaker or disconnect. Wait 3 minutes and restart the ice machine.

E38 – UI Comm Event – the User Interface display screen is not communicating with the control board.

Where can you find training?

As ice machines become increasingly complex, it can be difficult for even the most experienced technicians to keep up with all the latest developments. Fortunately, resources are available to help you stay updated on the latest trends and best practices using online ice machine training. One such resource is our collection of articles that deal with some of the more complex topics related to ice machines. So, if you want to take your Manitowoc ice service training to the next level, consider checking out some of the articles on our site. Online training programs are also available for all experience levels. An online training session can be undertaken anywhere a quality internet connection is available. Whether you’re a seasoned pro or just starting out in the field, you’ll find valuable insights and advice in these articles that can help you provide better service to your customers. Hands on training is generally gathered working with employers and factory service manuals in the field.

Factory service school training is available if you can travel with a larger training budget. Due to the complexities of ice machines participants in the advanced factory schools should have a moderate skill level related to commercial ice machines. Experience with light commercial refrigeration service is also recommended. Hands on training is provided onsite with the factory personnel supervision.